feed.xml

<?xml version="1.0" encoding="utf-8"?><feed xmlns="http://www.w3.org/2005/Atom" ><generator uri="https://jekyllrb.com/" version="3.6.0">Jekyll</generator><link href="https://pranavprakash.net/feed.xml" rel="self" type="application/atom+xml" /><link href="https://pranavprakash.net/" rel="alternate" type="text/html" /><updated>2017-10-18T15:44:33+05:30</updated><id>https://pranavprakash.net/</id><title type="html">Pranav Prakash</title><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><entry><title type="html">Debugging ES2017 async/await in VS Code using Source Maps</title><link href="https://pranavprakash.net/2017/10/18/debugging-es2017-async-await-in-vs-code-using-source-maps/" rel="alternate" type="text/html" title="Debugging ES2017 async/await in VS Code using Source Maps" /><published>2017-10-18T14:38:54+05:30</published><updated>2017-10-18T14:38:54+05:30</updated><id>https://pranavprakash.net/2017/10/18/debugging-es2017-async-await-in-vs-code-using-source-maps</id><content type="html" xml:base="https://pranavprakash.net/2017/10/18/debugging-es2017-async-await-in-vs-code-using-source-maps/">&lt;p&gt;&lt;code class=&quot;highlighter-rouge&quot;&gt;async/await&lt;/code&gt; has been the most promising feature of ES2017. It allows you to write asynchronous code in more elegant way saving you from the hassles of callback. &lt;code class=&quot;highlighter-rouge&quot;&gt;async/await&lt;/code&gt; is supported from Node versions &amp;gt;= 8.5. However if you are writing JavaScript code targeting Node versions &amp;lt; 8.5, you need to set up a transpiler like Babel to convert your code compatible to your version of Node. To debug in this scenario, you need to make sure that &lt;a href=&quot;https://www.html5rocks.com/en/tutorials/developertools/sourcemaps/&quot;&gt;Source Maps&lt;/a&gt; are generated and are linked in transpiled version generated by Babel. To do so, add following parameters in your &lt;code class=&quot;highlighter-rouge&quot;&gt;.babelrc&lt;/code&gt; file:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;s2&quot;&gt;&quot;sourceMaps&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;retainLines&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;!--more--&gt;

&lt;p&gt;For more details about &lt;code class=&quot;highlighter-rouge&quot;&gt;.babelrc&lt;/code&gt;, refer &lt;a href=&quot;https://babeljs.io/docs/usage/babelrc/&quot;&gt;this&lt;/a&gt;. Now add following configuration to &lt;code class=&quot;highlighter-rouge&quot;&gt;launch.json&lt;/code&gt; file:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;version&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;0.2.0&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;configurations&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;name&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;Launch&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;node&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;request&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;launch&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;program&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;${workspaceRoot}/dist/index.js&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;stopOnEntry&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;false&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;args&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[],&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;cwd&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;${workspaceRoot}&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;preLaunchTask&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;null&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;runtimeExecutable&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;nodemon&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;restart&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;runtimeArgs&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;--nolazy&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;],&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;env&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;NODE_ENV&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;development&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;console&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;internalConsole&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;sourceMaps&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;outFiles&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;${workspaceRoot}/dist/**/*.js&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;],&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;skipFiles&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;${workspaceRoot}/node_modules/**/*.js&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&amp;lt;node_internals&amp;gt;/**/*.js&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;],&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;smartStep&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Here in line number &lt;code class=&quot;highlighter-rouge&quot;&gt;8&lt;/code&gt;, &lt;code class=&quot;highlighter-rouge&quot;&gt;program&lt;/code&gt; points to entry point of your transpiled code. We are also setting &lt;code class=&quot;highlighter-rouge&quot;&gt;sourceMaps&lt;/code&gt; parameter to &lt;code class=&quot;highlighter-rouge&quot;&gt;true&lt;/code&gt; in line number &lt;code class=&quot;highlighter-rouge&quot;&gt;20&lt;/code&gt;. The &lt;code class=&quot;highlighter-rouge&quot;&gt;outFiles&lt;/code&gt; parameter in line number &lt;code class=&quot;highlighter-rouge&quot;&gt;21&lt;/code&gt; contains a glob pattern for an absolute path that matches our &lt;code class=&quot;highlighter-rouge&quot;&gt;.js&lt;/code&gt; files. We also don’t want to debug the Node internal programs and programs in &lt;code class=&quot;highlighter-rouge&quot;&gt;node_modules&lt;/code&gt; folder and hence they are specified in &lt;code class=&quot;highlighter-rouge&quot;&gt;skipFiles&lt;/code&gt; parameter in line number &lt;code class=&quot;highlighter-rouge&quot;&gt;22&lt;/code&gt;. Finally I have set the &lt;code class=&quot;highlighter-rouge&quot;&gt;smartStep&lt;/code&gt; to &lt;code class=&quot;highlighter-rouge&quot;&gt;true&lt;/code&gt; in line number &lt;code class=&quot;highlighter-rouge&quot;&gt;26&lt;/code&gt; to automatically step over code that doesn’t map to source files. These codes are generally injected by compiler during &lt;code class=&quot;highlighter-rouge&quot;&gt;async/await&lt;/code&gt; downcompilation. &lt;code class=&quot;highlighter-rouge&quot;&gt;smartStep&lt;/code&gt; will automatically step through code not covered by a source map until it reaches a location that is covered by a source map again.&lt;/p&gt;

&lt;p&gt;Now before starting debugging, make sure the transpiled code is availabe in directory specified in configuration file above. Also make sure source maps are generated and are present along with &lt;code class=&quot;highlighter-rouge&quot;&gt;.js&lt;/code&gt; files. Once everything is in place, just press &lt;code class=&quot;highlighter-rouge&quot;&gt;F5&lt;/code&gt; and start debugging.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Nodejs" /><category term="Javascript" /><category term="ES2017" /><category term="VS Code" /><summary type="html">async/await has been the most promising feature of ES2017. It allows you to write asynchronous code in more elegant way saving you from the hassles of callback. async/await is supported from Node versions &amp;gt;= 8.5. However if you are writing JavaScript code targeting Node versions &amp;lt; 8.5, you need to set up a transpiler like Babel to convert your code compatible to your version of Node. To debug in this scenario, you need to make sure that Source Maps are generated and are linked in transpiled version generated by Babel. To do so, add following parameters in your .babelrc file: 1 2 &quot;sourceMaps&quot;: true, &quot;retainLines&quot;: true</summary></entry><entry><title type="html">Building a fast text suggester using Node.js, Koa2 and Elasticsearch</title><link href="https://pranavprakash.net/2017/09/30/building-a-fast-text-suggester-using-node-js-koa2-and-elasticsearch/" rel="alternate" type="text/html" title="Building a fast text suggester using Node.js, Koa2 and Elasticsearch" /><published>2017-09-30T12:31:09+05:30</published><updated>2017-09-30T12:31:09+05:30</updated><id>https://pranavprakash.net/2017/09/30/building-a-fast-text-suggester-using-node-js-koa2-and-elasticsearch</id><content type="html" xml:base="https://pranavprakash.net/2017/09/30/building-a-fast-text-suggester-using-node-js-koa2-and-elasticsearch/">&lt;p&gt;In this blog post, I’ll show you how to create a fast text suggester using Koa2 framework of Node.js backed by Elasticsearch. &lt;a href=&quot;http://koajs.com/&quot;&gt;Koa2&lt;/a&gt; is a minimalist framework developed by team behind &lt;a href=&quot;http://expressjs.com/&quot;&gt;Express.js&lt;/a&gt; and comes with no middlewares inbuilt. &lt;a href=&quot;https://www.elastic.co/products/elasticsearch&quot;&gt;Elasticsearch&lt;/a&gt; is a distributed search engine which comes with handy features for doing full text search.&lt;/p&gt;

&lt;p&gt;To start with, I’ll use the &lt;a href=&quot;https://www.npmjs.com/package/koa-api-generator&quot;&gt;koa-api-generator&lt;/a&gt; to bootstrap the application. Start by issuing following commands&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;npm i &lt;span class=&quot;nt&quot;&gt;-g&lt;/span&gt; koa-api-generator
koa-api node-search-engine &lt;span class=&quot;o&quot;&gt;&amp;amp;&amp;amp;&lt;/span&gt; &lt;span class=&quot;nb&quot;&gt;cd &lt;/span&gt;node-search-engine
npm install&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;!--more--&gt;

&lt;p&gt;Now  I’ll install the &lt;code class=&quot;highlighter-rouge&quot;&gt;elasticsearch&lt;/code&gt; package to connect to Elasticsearch.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;npm i elasticsearch &lt;span class=&quot;nt&quot;&gt;--save&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;I’ll assume that you have installed and configured the Elasticsearch on your machine. If not then follow the installation guide &lt;a href=&quot;https://www.elastic.co/guide/en/elasticsearch/reference/current/_installation.html&quot;&gt;here&lt;/a&gt; to set up Elasticsearch on your machine. Next thing we need to do is to create an &lt;code class=&quot;highlighter-rouge&quot;&gt;index&lt;/code&gt; and define &lt;code class=&quot;highlighter-rouge&quot;&gt;mapping&lt;/code&gt; in Elasticsearch so that it can know how to map the data that is going to be stored in it, in order to serve results faster. To do so, I’ll use Elasticsearch’s HTTP APIs by issuing following curl request from command line:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;curl &lt;span class=&quot;nt&quot;&gt;-X&lt;/span&gt; PUT &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  http://localhost:9200/persons/ &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-H&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'content-type: application/json'&lt;/span&gt; &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'{
    &quot;mappings&quot;:{
        &quot;person&quot;:{
            &quot;properties&quot;:{
                &quot;name&quot;:{
                    &quot;type&quot;:&quot;string&quot;
                },
                &quot;suggest&quot;:{
                    &quot;type&quot;:&quot;completion&quot;
                }
            }
        }
    }
}'&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;This request creates an index &lt;code class=&quot;highlighter-rouge&quot;&gt;persons&lt;/code&gt; having type &lt;code class=&quot;highlighter-rouge&quot;&gt;person&lt;/code&gt; with property &lt;code class=&quot;highlighter-rouge&quot;&gt;name&lt;/code&gt;. The &lt;code class=&quot;highlighter-rouge&quot;&gt;suggest&lt;/code&gt; field would be used for completion and hence type has been specified as &lt;code class=&quot;highlighter-rouge&quot;&gt;completion&lt;/code&gt;. Now I will create a module &lt;code class=&quot;highlighter-rouge&quot;&gt;elasticService.js&lt;/code&gt; which can be imported wherever I want to interact with Elasticsearch.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-js&quot; data-lang=&quot;js&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;k&quot;&gt;import&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticsearch&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;from&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;elasticsearch&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;

&lt;span class=&quot;kd&quot;&gt;const&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticClient&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;new&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticsearch&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;Client&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;({&lt;/span&gt;
    &lt;span class=&quot;na&quot;&gt;host&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;localhost:9200&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
    &lt;span class=&quot;na&quot;&gt;log&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;info&quot;&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;});&lt;/span&gt;

&lt;span class=&quot;kd&quot;&gt;const&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{};&lt;/span&gt;
&lt;span class=&quot;kd&quot;&gt;const&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;index&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;persons&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;kd&quot;&gt;const&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;type&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;person&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;

&lt;span class=&quot;cm&quot;&gt;/**
 * Add a person
 */&lt;/span&gt;

&lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;addPerson&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;name&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;return&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticClient&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;index&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;({&lt;/span&gt;
        &lt;span class=&quot;nx&quot;&gt;index&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;nx&quot;&gt;type&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;na&quot;&gt;body&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
            &lt;span class=&quot;nx&quot;&gt;name&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
            &lt;span class=&quot;na&quot;&gt;suggest&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;name&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;split&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot; &quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
        &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
    &lt;span class=&quot;p&quot;&gt;});&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;};&lt;/span&gt;

&lt;span class=&quot;cm&quot;&gt;/**
 * Fetch suggestions
 */&lt;/span&gt;

&lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;getSuggestions&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;input&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;return&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticClient&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;suggest&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;({&lt;/span&gt;
        &lt;span class=&quot;nx&quot;&gt;index&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;na&quot;&gt;body&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
            &lt;span class=&quot;na&quot;&gt;persons&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                &lt;span class=&quot;na&quot;&gt;prefix&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;input&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                &lt;span class=&quot;na&quot;&gt;completion&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                    &lt;span class=&quot;na&quot;&gt;field&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;suggest&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;na&quot;&gt;fuzzy&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;kc&quot;&gt;true&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;na&quot;&gt;size&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;10&lt;/span&gt;
                &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
            &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
        &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
    &lt;span class=&quot;p&quot;&gt;});&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;};&lt;/span&gt;

&lt;span class=&quot;k&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;default&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;&lt;code class=&quot;highlighter-rouge&quot;&gt;addPerson&lt;/code&gt; function is just adding the name of person to index &lt;code class=&quot;highlighter-rouge&quot;&gt;persons&lt;/code&gt; and populating &lt;code class=&quot;highlighter-rouge&quot;&gt;suggest&lt;/code&gt; field with array of strings obtained after splitting the &lt;code class=&quot;highlighter-rouge&quot;&gt;name&lt;/code&gt;. For example, if &lt;code class=&quot;highlighter-rouge&quot;&gt;name&lt;/code&gt; is &lt;code class=&quot;highlighter-rouge&quot;&gt;Pranav Prakash&lt;/code&gt;, suggest field will contain &lt;code class=&quot;highlighter-rouge&quot;&gt;[&quot;Pranav&quot;, &quot;Prakash&quot;]&lt;/code&gt;. &lt;code class=&quot;highlighter-rouge&quot;&gt;getSuggestions&lt;/code&gt; uses &lt;a href=&quot;https://www.elastic.co/guide/en/elasticsearch/reference/current/search-suggesters-completion.html&quot;&gt;Completion Suggester&lt;/a&gt; api to return suggestions. I have set the &lt;code class=&quot;highlighter-rouge&quot;&gt;fuzzy&lt;/code&gt; searching &lt;code class=&quot;highlighter-rouge&quot;&gt;true&lt;/code&gt; which will return results even if we have typo in search input. The &lt;code class=&quot;highlighter-rouge&quot;&gt;size&lt;/code&gt; parameters simply restricts the number of suggestion which in this case has been set to 10. Now since our module is complete, I will integrate it with Koa routes. I’ve populated the &lt;code class=&quot;highlighter-rouge&quot;&gt;routes.js&lt;/code&gt; with two routes as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-js&quot; data-lang=&quot;js&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;k&quot;&gt;import&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;Router&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;from&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;koa-router&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;import&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;from&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;./elasticService&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;

&lt;span class=&quot;kd&quot;&gt;const&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;router&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;new&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;Router&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;();&lt;/span&gt;

&lt;span class=&quot;cm&quot;&gt;/**
 * Get suggestions
 */&lt;/span&gt;

&lt;span class=&quot;nx&quot;&gt;router&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;kd&quot;&gt;get&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;/suggest/:term&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;async&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;body&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;kr&quot;&gt;await&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;getSuggestions&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;params&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;term&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;);&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;});&lt;/span&gt;

&lt;span class=&quot;cm&quot;&gt;/**
 * Create person
 */&lt;/span&gt;

&lt;span class=&quot;nx&quot;&gt;router&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;post&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;/&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;async&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;body&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;kr&quot;&gt;await&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;elasticService&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;addPerson&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;ctx&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;request&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;body&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nx&quot;&gt;name&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;);&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;});&lt;/span&gt;

&lt;span class=&quot;k&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;default&lt;/span&gt; &lt;span class=&quot;nx&quot;&gt;router&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;These routes are quite simple: &lt;code class=&quot;highlighter-rouge&quot;&gt;get(&quot;suggest/:term&quot;)&lt;/code&gt; route is returning the suggestions and &lt;code class=&quot;highlighter-rouge&quot;&gt;post(&quot;/&quot;)&lt;/code&gt; route adds a person to Elasticsearch. Now we’ll start the server using following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;npm run dev&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now I need to add some data in Elasticsearch so that I can perform searches on it. I’ll add some data by issuing following &lt;code class=&quot;highlighter-rouge&quot;&gt;POST&lt;/code&gt; requests from command line:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;curl &lt;span class=&quot;nt&quot;&gt;-X&lt;/span&gt; POST &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  http://localhost:8080/ &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-H&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'content-type: application/json'&lt;/span&gt; &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'{
    &quot;name&quot; : &quot;Ranbir Kapoor&quot;
}'&lt;/span&gt;

curl &lt;span class=&quot;nt&quot;&gt;-X&lt;/span&gt; POST &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  http://localhost:8080/ &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-H&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'content-type: application/json'&lt;/span&gt; &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'{
    &quot;name&quot; : &quot;Ranvir Singh&quot;
}'&lt;/span&gt;

curl &lt;span class=&quot;nt&quot;&gt;-X&lt;/span&gt; POST &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  http://localhost:8080/ &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-H&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'content-type: application/json'&lt;/span&gt; &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'{
    &quot;name&quot; : &quot;Ranveer Singh&quot;
}'&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now I’ll query the application using commands below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;curl &lt;span class=&quot;nt&quot;&gt;-X&lt;/span&gt; GET &lt;span class=&quot;se&quot;&gt;\&lt;/span&gt;
  http://localhost:8080/suggest/ranbir&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;And voila, I’m presented with results below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-js&quot; data-lang=&quot;js&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;s2&quot;&gt;&quot;_shards&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
        &lt;span class=&quot;s2&quot;&gt;&quot;total&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;s2&quot;&gt;&quot;successful&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;s2&quot;&gt;&quot;skipped&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
        &lt;span class=&quot;s2&quot;&gt;&quot;failed&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;
    &lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;
    &lt;span class=&quot;s2&quot;&gt;&quot;persons&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;
        &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
            &lt;span class=&quot;s2&quot;&gt;&quot;text&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;ranbir&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
            &lt;span class=&quot;s2&quot;&gt;&quot;offset&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
            &lt;span class=&quot;s2&quot;&gt;&quot;length&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;6&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
            &lt;span class=&quot;s2&quot;&gt;&quot;options&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;
                &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;text&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Ranbir&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_index&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;persons&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;person&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_id&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;AV7Sns-uOy-E67GQK4As&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_source&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                        &lt;span class=&quot;s2&quot;&gt;&quot;name&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Ranbir Kapoor&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                        &lt;span class=&quot;s2&quot;&gt;&quot;suggest&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;
                            &lt;span class=&quot;s2&quot;&gt;&quot;Ranbir&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                            &lt;span class=&quot;s2&quot;&gt;&quot;Kapoor&quot;&lt;/span&gt;
                        &lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;
                    &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
                &lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;
                &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;text&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Ranvir&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_index&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;persons&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;person&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_id&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;AV7SnraQOy-E67GQK4Ar&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;3&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                    &lt;span class=&quot;s2&quot;&gt;&quot;_source&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;
                        &lt;span class=&quot;s2&quot;&gt;&quot;name&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Ranvir Singh&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                        &lt;span class=&quot;s2&quot;&gt;&quot;suggest&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;
                            &lt;span class=&quot;s2&quot;&gt;&quot;Ranvir&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;
                            &lt;span class=&quot;s2&quot;&gt;&quot;Singh&quot;&lt;/span&gt;
                        &lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;
                    &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
                &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
            &lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;
        &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;
    &lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;
&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Notice how fuzzy searching has returned results for both &lt;code class=&quot;highlighter-rouge&quot;&gt;Ranbir&lt;/code&gt; as well as &lt;code class=&quot;highlighter-rouge&quot;&gt;Ravir&lt;/code&gt;, pretty neat, eh? Only difference is in their &lt;code class=&quot;highlighter-rouge&quot;&gt;score&lt;/code&gt; which Elasticsearch calculates internally based on how well the query term matches with current result.&lt;/p&gt;

&lt;p&gt;The complete source code for this project is available on Github &lt;a href=&quot;https://github.com/pranavpr/node-search-engine&quot;&gt;here&lt;/a&gt;. This post just scrathces the surface of what can be done with Elasticsearch. You can dive deeper by specifying &lt;code class=&quot;highlighter-rouge&quot;&gt;weight&lt;/code&gt; for suggestions, trying out different &lt;code class=&quot;highlighter-rouge&quot;&gt;analyser&lt;/code&gt; and &lt;code class=&quot;highlighter-rouge&quot;&gt;search_analyzer&lt;/code&gt;, increasing or decreasing &lt;code class=&quot;highlighter-rouge&quot;&gt;fuzziness&lt;/code&gt; or using &lt;code class=&quot;highlighter-rouge&quot;&gt;regex&lt;/code&gt; queries depending on your use case.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Nodejs" /><category term="Elasticsearch" /><category term="Koa2" /><summary type="html">In this blog post, I’ll show you how to create a fast text suggester using Koa2 framework of Node.js backed by Elasticsearch. Koa2 is a minimalist framework developed by team behind Express.js and comes with no middlewares inbuilt. Elasticsearch is a distributed search engine which comes with handy features for doing full text search. To start with, I’ll use the koa-api-generator to bootstrap the application. Start by issuing following commands 1 2 3 npm i -g koa-api-generator koa-api node-search-engine &amp;amp;&amp;amp; cd node-search-engine npm install</summary></entry><entry><title type="html">Case insensitive exact match search in Elasticsearch</title><link href="https://pranavprakash.net/2017/09/13/case-insensitive-exact-match-search-in-elasticsearch/" rel="alternate" type="text/html" title="Case insensitive exact match search in Elasticsearch" /><published>2017-09-13T16:31:32+05:30</published><updated>2017-09-13T16:31:32+05:30</updated><id>https://pranavprakash.net/2017/09/13/case-insensitive-exact-match-search-in-elasticsearch</id><content type="html" xml:base="https://pranavprakash.net/2017/09/13/case-insensitive-exact-match-search-in-elasticsearch/">&lt;p&gt;I had a requirement where I needed to do exact match search in ElasticSearch. After searching a bit I landed to &lt;a href=&quot;https://www.elastic.co/guide/en/elasticsearch/guide/current/_finding_exact_values.html&quot;&gt;this&lt;/a&gt; page of ElasticSearch documentation. I was thrilled that I got the solution quickly (thanking god and ElasticSearch team in my mind). Hence I started testing by creating an index using request below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;err&quot;&gt;PUT&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;mappings&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;product&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;properties&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;string&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;index&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;not_analyzed&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;!--more--&gt;

&lt;p&gt;Then I added some data using request below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;err&quot;&gt;POST&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;Green Ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;

&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;POST&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;Red Ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;

&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;POST&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;Yellow Ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now it was time for testing and hence I fired following request:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;err&quot;&gt;POST&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/product/_search&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;query&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;constant_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;filter&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;term&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;green ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;And I was presented with following:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;took&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;timed_out&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;false&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_shards&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;total&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;successful&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;skipped&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;failed&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;hits&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;total&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;max_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;null&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;hits&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:[]&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;I was surprised (and frustrated at the same time) as the data was there in ElasticSearch, still it was not returning the data. Soon enough I found that it was because the search was case sensitive and searching with “Green Ball” returned result. This was unacceptable in my use case as I needed case insensitive search. After searching a little bit more, I found that I have to create an analyzer with &lt;code class=&quot;highlighter-rouge&quot;&gt;lowercase&lt;/code&gt; filter and use this to analyze the field on which I want to perform search. Hence I deleted the index and recreated it as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;err&quot;&gt;DELETE&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;

&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;PUT&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;settings&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;index&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;analysis&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;analyzer&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;analyzer_case_insensitive&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
            &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;tokenizer&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;keyword&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
            &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;filter&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;lowercase&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;mappings&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;product&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;properties&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;string&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;analyzer&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;analyzer_case_insensitive&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;I needed to switch to &lt;code class=&quot;highlighter-rouge&quot;&gt;match&lt;/code&gt; query as &lt;code class=&quot;highlighter-rouge&quot;&gt;term&lt;/code&gt; query would return result with only lower case search text. Below is the modified query:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;err&quot;&gt;POST&lt;/span&gt;&lt;span class=&quot;w&quot;&gt; &lt;/span&gt;&lt;span class=&quot;err&quot;&gt;localhost&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;9200&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;/products/product/_search&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;query&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;match&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;greeN ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;And this resulted in following:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-json&quot; data-lang=&quot;json&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;took&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;timed_out&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;kc&quot;&gt;false&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_shards&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;total&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;successful&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;skipped&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;failed&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;},&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;hits&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;total&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;1&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;max_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mf&quot;&gt;0.6931472&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;hits&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:[&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_index&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;products&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_type&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;product&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_id&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;AV57L6vzqKOq3BnmUAzd&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_score&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;mf&quot;&gt;0.6931472&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;_source&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:{&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
          &lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;productName&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;Green Ball&quot;&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
        &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
      &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
    &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
  &lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;w&quot;&gt;
&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;}&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;I was happy with the result as it served my purpose. Let me know in comments if there is a better way to achieve this.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Elasticsearch" /><summary type="html">I had a requirement where I needed to do exact match search in ElasticSearch. After searching a bit I landed to this page of ElasticSearch documentation. I was thrilled that I got the solution quickly (thanking god and ElasticSearch team in my mind). Hence I started testing by creating an index using request below: 1 2 3 4 5 6 7 8 9 10 11 12 13 PUT localhost:9200/products/ { &quot;mappings&quot;: { &quot;product&quot;: { &quot;properties&quot;: { &quot;productName&quot;: { &quot;type&quot;: &quot;string&quot;, &quot;index&quot;: &quot;not_analyzed&quot; } } } } }</summary></entry><entry><title type="html">Automated PostgreSQL backups</title><link href="https://pranavprakash.net/2017/05/16/automated-postgresql-backups/" rel="alternate" type="text/html" title="Automated PostgreSQL backups" /><published>2017-05-16T11:59:50+05:30</published><updated>2017-05-16T11:59:50+05:30</updated><id>https://pranavprakash.net/2017/05/16/automated-postgresql-backups</id><content type="html" xml:base="https://pranavprakash.net/2017/05/16/automated-postgresql-backups/">&lt;p&gt;Recently we migrated one of our applications from MongoDB to PostgreSQL (which is a story for another time) at work. Similar to the script I developed for MongoDB in my last &lt;a href=&quot;/2017/02/04/automate-mongodb-backups-using-cron-and-shell-script/&quot;&gt;blog post&lt;/a&gt;, I developed one for PostgreSQL. &lt;code class=&quot;highlighter-rouge&quot;&gt;pg_dump&lt;/code&gt; utility of PostgreSQL provides some nifty &lt;a href=&quot;https://www.postgresql.org/docs/9.6/static/app-pgdump.html&quot;&gt;options&lt;/a&gt; to create different formats to create backup files. My script produces two types of backup files:&lt;/p&gt;

&lt;ul&gt;
  &lt;li&gt;Plain bakup - This produces a gzipepd version of SQL script file which you can execute to restore the database.&lt;/li&gt;
  &lt;li&gt;Custom backup - This produces a compressed custom-format archive suitable for input into &lt;code class=&quot;highlighter-rouge&quot;&gt;pg_restore&lt;/code&gt;.&lt;/li&gt;
&lt;/ul&gt;

&lt;!--more--&gt;

&lt;p&gt;Without further ado, below is the script:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c&quot;&gt;#!/bin/bash&lt;/span&gt;

&lt;span class=&quot;c&quot;&gt;##############################&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;## POSTGRESQL BACKUP CONFIG ##&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;##############################&lt;/span&gt;
 
&lt;span class=&quot;c&quot;&gt;# Optional hostname to adhere to pg_hba policies.  Will default to &quot;localhost&quot; if none specified.&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;HOSTNAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;127.0.0.1
 
&lt;span class=&quot;c&quot;&gt;# Optional username to connect to database as.  Will default to &quot;postgres&quot; if none specified.&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;USERNAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;pgusername
 
&lt;span class=&quot;c&quot;&gt;# This dir will be created if it doesn't exist.  This must be writable by the user the script is&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# running as.&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;/var/backups/

&lt;span class=&quot;c&quot;&gt;# Database name to backup&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DATABASE&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;mydb
 
&lt;span class=&quot;c&quot;&gt;# Will produce a custom-format backup if set to &quot;yes&quot;&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;ENABLE_CUSTOM_BACKUPS&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;yes
 
&lt;span class=&quot;c&quot;&gt;# Will produce a gzipped plain-format backup if set to &quot;yes&quot;&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;ENABLE_PLAIN_BACKUPS&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;yes

&lt;span class=&quot;c&quot;&gt;#### SETTINGS FOR ROTATED BACKUPS ####&lt;/span&gt;

&lt;span class=&quot;c&quot;&gt;# Number of days to keep daily backups&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DAYS_TO_KEEP&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;14

 
&lt;span class=&quot;c&quot;&gt;###########################&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;### INITIALISE DEFAULTS ###&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;###########################&lt;/span&gt;
 
&lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$HOSTNAME&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
  &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;HOSTNAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;localhost&quot;&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;fi&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
 
&lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$USERNAME&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
  &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;USERNAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;postgres&quot;&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;fi&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
 
 
&lt;span class=&quot;c&quot;&gt;###########################&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;#### START THE BACKUPS ####&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;###########################&lt;/span&gt;
 
&lt;span class=&quot;k&quot;&gt;function &lt;/span&gt;perform_backups&lt;span class=&quot;o&quot;&gt;()&lt;/span&gt;
&lt;span class=&quot;o&quot;&gt;{&lt;/span&gt;
  &lt;span class=&quot;nv&quot;&gt;SUFFIX&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$1&lt;/span&gt;
  &lt;span class=&quot;nv&quot;&gt;FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;date +&lt;span class=&quot;se&quot;&gt;\%&lt;/span&gt;Y-&lt;span class=&quot;se&quot;&gt;\%&lt;/span&gt;m-&lt;span class=&quot;se&quot;&gt;\%&lt;/span&gt;d&lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$SUFFIX&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;/&quot;&lt;/span&gt;
 
  &lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Making backup directory in &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
 
  &lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; mkdir &lt;span class=&quot;nt&quot;&gt;-p&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
    &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Cannot create backup directory in &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;. Go and fix it!&quot;&lt;/span&gt; 1&amp;gt;&amp;amp;2
    &lt;span class=&quot;nb&quot;&gt;exit &lt;/span&gt;1&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
  &lt;span class=&quot;k&quot;&gt;fi&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
 
  &lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-e&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;se&quot;&gt;\n\n&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;Performing full backup of &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
  &lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-e&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;--------------------------------------------&lt;/span&gt;&lt;span class=&quot;se&quot;&gt;\n&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
 
    &lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$ENABLE_PLAIN_BACKUPS&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;yes&quot;&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;]&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;then
      &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Plain backup of &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
 
      &lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; pg_dump &lt;span class=&quot;nt&quot;&gt;-Fp&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-h&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$HOSTNAME&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-U&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$USERNAME&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; | gzip &lt;span class=&quot;o&quot;&gt;&amp;gt;&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.sql.gz.in_progress&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
        &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;[!!ERROR!!] Failed to produce plain backup database &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; 1&amp;gt;&amp;amp;2
      &lt;span class=&quot;k&quot;&gt;else
        &lt;/span&gt;mv &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.sql.gz.in_progress &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.sql.gz
      &lt;span class=&quot;k&quot;&gt;fi
    fi
 
    if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$ENABLE_CUSTOM_BACKUPS&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;yes&quot;&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;]&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;then
      &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Custom backup of &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
 
      &lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; pg_dump &lt;span class=&quot;nt&quot;&gt;-Fc&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-h&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$HOSTNAME&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-U&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$USERNAME&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-f&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.custom.in_progress&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
        &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;[!!ERROR!!] Failed to produce custom backup database &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
      &lt;span class=&quot;k&quot;&gt;else
        &lt;/span&gt;mv &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.custom.in_progress &lt;span class=&quot;nv&quot;&gt;$FINAL_BACKUP_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;.custom
      &lt;span class=&quot;k&quot;&gt;fi
    fi
 
  &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-e&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;se&quot;&gt;\n&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;Database backup complete!&quot;&lt;/span&gt;
&lt;span class=&quot;o&quot;&gt;}&lt;/span&gt;
 
&lt;span class=&quot;c&quot;&gt;# DAILY BACKUPS&lt;/span&gt;
 
&lt;span class=&quot;c&quot;&gt;# Delete daily backups older than DAYS_TO_KEEP&lt;/span&gt;
find &lt;span class=&quot;nv&quot;&gt;$BACKUP_DIR&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-maxdepth&lt;/span&gt; 1 &lt;span class=&quot;nt&quot;&gt;-mtime&lt;/span&gt; +&lt;span class=&quot;nv&quot;&gt;$DAYS_TO_KEEP&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-name&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;*-daily&quot;&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-exec&lt;/span&gt; rm &lt;span class=&quot;nt&quot;&gt;-rf&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'{}'&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;';'&lt;/span&gt;

perform_backups &lt;span class=&quot;s2&quot;&gt;&quot;-daily&quot;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Save this in a file named &lt;code class=&quot;highlighter-rouge&quot;&gt;pgbackup.sh&lt;/code&gt;. After that you need to make the file executable by issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;chomd +x pgbackup.sh&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;You must be wondering about where to specify the database password. Well as per PostgreSQL &lt;a href=&quot;https://www.postgresql.org/docs/current/static/libpq-pgpass.html&quot;&gt;documentation&lt;/a&gt;, you need to create password file &lt;code class=&quot;highlighter-rouge&quot;&gt;.pgpass&lt;/code&gt; in user’s home directory and should contain lines of the following format:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;hostname:port:database:username:password&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Make sure the permissions on &lt;code class=&quot;highlighter-rouge&quot;&gt;.pgpass&lt;/code&gt; must disallow any access to world or group. You can do this my issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;chmod 0600 ~/.pgpass&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;This password file is automatically referanced by &lt;code class=&quot;highlighter-rouge&quot;&gt;pgdump&lt;/code&gt; utility whenever invoked. Finally you need to create a cron job to execute the &lt;code class=&quot;highlighter-rouge&quot;&gt;pgbackup.sh&lt;/code&gt; script automatically. Issue following command to create a cron job:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;crontab &lt;span class=&quot;nt&quot;&gt;-e&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Enter following:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c&quot;&gt;# PostgreSQL Backup&lt;/span&gt;
00 00 &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; /path/to/script/pgbackup.sh&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Save the file by pressing &lt;code class=&quot;highlighter-rouge&quot;&gt;Esc&lt;/code&gt;and then &lt;code class=&quot;highlighter-rouge&quot;&gt;wq&lt;/code&gt; + &lt;code class=&quot;highlighter-rouge&quot;&gt;Enter&lt;/code&gt; (similar to vi editor). This cron job will execute the backup script at 12 o’clock every night creating your database backups.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="PostgreSQL" /><category term="Cron" /><category term="Shell" /><category term="DevOps" /><summary type="html">Recently we migrated one of our applications from MongoDB to PostgreSQL (which is a story for another time) at work. Similar to the script I developed for MongoDB in my last blog post, I developed one for PostgreSQL. pg_dump utility of PostgreSQL provides some nifty options to create different formats to create backup files. My script produces two types of backup files: Plain bakup - This produces a gzipepd version of SQL script file which you can execute to restore the database. Custom backup - This produces a compressed custom-format archive suitable for input into pg_restore.</summary></entry><entry><title type="html">Automate MongoDB backups using Cron and Shell Script</title><link href="https://pranavprakash.net/2017/02/04/automate-mongodb-backups-using-cron-and-shell-script/" rel="alternate" type="text/html" title="Automate MongoDB backups using Cron and Shell Script" /><published>2017-02-04T19:07:36+05:30</published><updated>2017-02-04T19:07:36+05:30</updated><id>https://pranavprakash.net/2017/02/04/automate-mongodb-backups-using-cron-and-shell-script</id><content type="html" xml:base="https://pranavprakash.net/2017/02/04/automate-mongodb-backups-using-cron-and-shell-script/">&lt;p&gt;After having a bitter experience of losing data due to execution of wrong command, I decided to backup my database regularly. Hence I wrote a simple shell script which backs up the database and produces gzipped version of backup files. Below is the shell script:&lt;/p&gt;

&lt;!--more--&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-shell&quot; data-lang=&quot;shell&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c&quot;&gt;#!/bin/sh&lt;/span&gt;

&lt;span class=&quot;c&quot;&gt;#=====================================================================&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Set the following variables as per your requirement&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;#=====================================================================&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Database Name to backup&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;MONGO_DATABASE&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;mydb&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Database host name&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;MONGO_HOST&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;127.0.0.1&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Database port&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;MONGO_PORT&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;27017&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Backup directory&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;BACKUPS_DIR&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;/var/backups/&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$MONGO_DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Database user name&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DBUSERNAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;username&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Database password&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DBPASSWORD&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;passw0rd&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Authentication database name&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DBAUTHDB&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;admin&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Days to keep the backup&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;DAYSTORETAINBACKUP&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;14&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;#=====================================================================&lt;/span&gt;

&lt;span class=&quot;nv&quot;&gt;TIMESTAMP&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;date +%F-%H%M&lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;
&lt;span class=&quot;nv&quot;&gt;BACKUP_NAME&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$MONGO_DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;-&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$TIMESTAMP&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;

&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Performing backup of &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$MONGO_DATABASE&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;&lt;/span&gt;
&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;--------------------------------------------&quot;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Create backup directory&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;!&lt;/span&gt; mkdir &lt;span class=&quot;nt&quot;&gt;-p&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$BACKUPS_DIR&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;then
  &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Can't create backup directory in &lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;$BACKUPS_DIR&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;. Go and fix it!&quot;&lt;/span&gt; 1&amp;gt;&amp;amp;2
  &lt;span class=&quot;nb&quot;&gt;exit &lt;/span&gt;1&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;fi&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Create dump&lt;/span&gt;
mongodump &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$MONGO_DATABASE&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;--username&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$DBUSERNAME&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;--password&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$DBPASSWORD&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;--authenticationDatabase&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$DBAUTHDB&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Rename dump directory to backup name&lt;/span&gt;
mv dump &lt;span class=&quot;nv&quot;&gt;$BACKUP_NAME&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Compress backup&lt;/span&gt;
&lt;span class=&quot;nb&quot;&gt;tar&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-zcvf&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$BACKUPS_DIR&lt;/span&gt;/&lt;span class=&quot;nv&quot;&gt;$BACKUP_NAME&lt;/span&gt;.tgz &lt;span class=&quot;nv&quot;&gt;$BACKUP_NAME&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Delete uncompressed backup&lt;/span&gt;
rm &lt;span class=&quot;nt&quot;&gt;-rf&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;$BACKUP_NAME&lt;/span&gt;
&lt;span class=&quot;c&quot;&gt;# Delete backups older than retention period&lt;/span&gt;
find &lt;span class=&quot;nv&quot;&gt;$BACKUPS_DIR&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-type&lt;/span&gt; f &lt;span class=&quot;nt&quot;&gt;-mtime&lt;/span&gt; +&lt;span class=&quot;nv&quot;&gt;$DAYSTORETAINBACKUP&lt;/span&gt; &lt;span class=&quot;nt&quot;&gt;-exec&lt;/span&gt; rm &lt;span class=&quot;o&quot;&gt;{}&lt;/span&gt; +
&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;--------------------------------------------&quot;&lt;/span&gt;
&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Database backup complete!&quot;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;You need to update the parameters in above shell script as per your environment. Specify the name of database to be backed up, host name, port in &lt;code class=&quot;highlighter-rouge&quot;&gt;MONGO_DATABASE&lt;/code&gt;, &lt;code class=&quot;highlighter-rouge&quot;&gt;MONGO_HOST&lt;/code&gt; and &lt;code class=&quot;highlighter-rouge&quot;&gt;MONGO_PORT&lt;/code&gt; parameters. To specify the backup directory, update the &lt;code class=&quot;highlighter-rouge&quot;&gt;BACKUPS_DIR&lt;/code&gt; parameter. You need to update the database credentials in &lt;code class=&quot;highlighter-rouge&quot;&gt;DBUSERNAME&lt;/code&gt;, &lt;code class=&quot;highlighter-rouge&quot;&gt;DBPASSWORD&lt;/code&gt; and &lt;code class=&quot;highlighter-rouge&quot;&gt;DBAUTHDB&lt;/code&gt; parameters if you are using one. Finally you need to specify the number of days you want to retain the backup file in &lt;code class=&quot;highlighter-rouge&quot;&gt;DAYSTORETAINBACKUP&lt;/code&gt; parameter. Once you update all the parameters as per your environment, save the file as &lt;code class=&quot;highlighter-rouge&quot;&gt;mongobackup.sh&lt;/code&gt;. After that you need to make the file executable by issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;chomd +x mongobackup.sh&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now you need to create a cron job to execute this script automatically. Issue following command to create a cron job:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;crontab &lt;span class=&quot;nt&quot;&gt;-e&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Enter following:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c&quot;&gt;# MongoDB Backup&lt;/span&gt;
00 00 &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;*&lt;/span&gt; /path/to/script/mongobackup.sh&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Save the file by pressing &lt;code class=&quot;highlighter-rouge&quot;&gt;Esc&lt;/code&gt;and then &lt;code class=&quot;highlighter-rouge&quot;&gt;wq&lt;/code&gt; + &lt;code class=&quot;highlighter-rouge&quot;&gt;Enter&lt;/code&gt; (similar to vi editor). This cron job will execute the backup script at 12 o’clock every night. You can head over to &lt;a href=&quot;https://crontab-generator.org&quot;&gt;this site&lt;/a&gt; to generate a cron entry of your liking.&lt;/p&gt;

&lt;p&gt;That’s it, sit back and relax. The script will execute every midnight, create backup files and will also delete the backup files older than specified in &lt;code class=&quot;highlighter-rouge&quot;&gt;DAYSTORETAINBACKUP&lt;/code&gt; parameter.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="DevOps" /><category term="MongoDB" /><category term="Cron" /><category term="Shell" /><summary type="html">After having a bitter experience of losing data due to execution of wrong command, I decided to backup my database regularly. Hence I wrote a simple shell script which backs up the database and produces gzipped version of backup files. Below is the shell script:</summary></entry><entry><title type="html">Kill idle connections to Redis</title><link href="https://pranavprakash.net/2016/02/05/kill-idle-connections-to-redis/" rel="alternate" type="text/html" title="Kill idle connections to Redis" /><published>2016-02-05T17:40:18+05:30</published><updated>2016-02-05T17:40:18+05:30</updated><id>https://pranavprakash.net/2016/02/05/kill-idle-connections-to-redis</id><content type="html" xml:base="https://pranavprakash.net/2016/02/05/kill-idle-connections-to-redis/">&lt;p&gt;I was using a Amazon Elasticache &lt;code class=&quot;highlighter-rouge&quot;&gt;cache.t2.medium&lt;/code&gt; Redis instance as a cache store for one of the Rails application. Over the time I observed that connections to Redis instance are increasing day by day and once it hit ~1500, the Rails application started throwing connection timeout exceptions:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;Error connecting to Redis on redis-host:6379 &lt;span class=&quot;o&quot;&gt;(&lt;/span&gt;Redis::TimeoutError&lt;span class=&quot;o&quot;&gt;)&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;On searching over internet, I found that the default parameter group has &lt;code class=&quot;highlighter-rouge&quot;&gt;timeout&lt;/code&gt; value set to 0 which means, any connection that has been initialized to redis will be kept by redis even if the connection initialized by the client is down. Well the first thing I did was to create a new parameter group and set its value to a non-zero integer. However I couldn’t apply the parameter group changes to live production application and hence started looking for alternatives.&lt;/p&gt;

&lt;!--more--&gt;

&lt;p&gt;On further investigation, I found that Redis provides &lt;code class=&quot;highlighter-rouge&quot;&gt;CLIENT KILL&lt;/code&gt; command to kill the client connections. To see all client connections to your Redis instance, you can use &lt;code class=&quot;highlighter-rouge&quot;&gt;CLIENT LIST&lt;/code&gt; command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;redis 127.0.0.1:6379&amp;gt; CLIENT LIST
&lt;span class=&quot;nv&quot;&gt;id&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;9115408 &lt;span class=&quot;nv&quot;&gt;addr&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;10.0.1.252:56348 &lt;span class=&quot;nv&quot;&gt;fd&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;95 &lt;span class=&quot;nv&quot;&gt;name&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;age&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;23 &lt;span class=&quot;nv&quot;&gt;idle&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;23 &lt;span class=&quot;nv&quot;&gt;flags&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;N &lt;span class=&quot;nv&quot;&gt;db&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;14 &lt;span class=&quot;nv&quot;&gt;sub&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;psub&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;multi&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;-1&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;qbuf&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 qbuf-free&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;obl&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;oll&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;omem&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;events&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;r &lt;span class=&quot;nv&quot;&gt;cmd&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;get
&lt;span class=&quot;nv&quot;&gt;id&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;9115336 &lt;span class=&quot;nv&quot;&gt;addr&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;10.0.2.151:52018 &lt;span class=&quot;nv&quot;&gt;fd&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;37 &lt;span class=&quot;nv&quot;&gt;name&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;age&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;107 &lt;span class=&quot;nv&quot;&gt;idle&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;107 &lt;span class=&quot;nv&quot;&gt;flags&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;N &lt;span class=&quot;nv&quot;&gt;db&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;14 &lt;span class=&quot;nv&quot;&gt;sub&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;psub&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;multi&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;-1&lt;/span&gt; &lt;span class=&quot;nv&quot;&gt;qbuf&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 qbuf-free&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;obl&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;oll&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;omem&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;0 &lt;span class=&quot;nv&quot;&gt;events&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;r &lt;span class=&quot;nv&quot;&gt;cmd&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;get&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;To kill a connection, you can use &lt;code class=&quot;highlighter-rouge&quot;&gt;CLIENT KILL&lt;/code&gt; command as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;redis 127.0.0.1:6379&amp;gt; CLIENT KILL 10.0.1.252:56348
&lt;span class=&quot;o&quot;&gt;(&lt;/span&gt;integer&lt;span class=&quot;o&quot;&gt;)&lt;/span&gt; 1&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;On successful completion, the command will return number of client connections killed. Well this was all good but I can’t kill ~1500 connections one by one. Hence I wrote a little python script to achieve this task.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-python&quot; data-lang=&quot;python&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;kn&quot;&gt;import&lt;/span&gt; &lt;span class=&quot;nn&quot;&gt;redis&lt;/span&gt;
&lt;span class=&quot;kn&quot;&gt;import&lt;/span&gt; &lt;span class=&quot;nn&quot;&gt;re&lt;/span&gt;

&lt;span class=&quot;n&quot;&gt;idle_max&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;mi&quot;&gt;300&lt;/span&gt;

&lt;span class=&quot;n&quot;&gt;r&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;redis&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;Redis&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;host&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;localhost&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;port&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;6379&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;password&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;bp&quot;&gt;None&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;n&quot;&gt;cl&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;r&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;execute_command&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;client&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&quot;list&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;

&lt;span class=&quot;n&quot;&gt;pattern&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;r&quot;addr=(.*?) .*? idle=(\d*)&quot;&lt;/span&gt;
&lt;span class=&quot;n&quot;&gt;regex&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;re&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;compile&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;pattern&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;for&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;match&lt;/span&gt; &lt;span class=&quot;ow&quot;&gt;in&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;regex&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;finditer&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;cl&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;):&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;nb&quot;&gt;int&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;match&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;group&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;2&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;))&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;&amp;gt;&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;idle_max&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;:&lt;/span&gt;
        &lt;span class=&quot;n&quot;&gt;r&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;execute_command&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;client&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&quot;kill&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;match&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;group&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;1&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;))&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Above script will kill all redis client connections which have been idle for 300 seconds. You can adjust the value of &lt;code class=&quot;highlighter-rouge&quot;&gt;idle_max&lt;/code&gt; variable as per your need. Save this script as &lt;code class=&quot;highlighter-rouge&quot;&gt;killredisconn.py&lt;/code&gt; and execute as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;python killredisconn.py&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;You need to install &lt;code class=&quot;highlighter-rouge&quot;&gt;redis&lt;/code&gt; python package before executing this command. You can install the same by issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;sudo &lt;/span&gt;pip install redis&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Once I executed above script, number of client connection decreased dramatically and connection timeout exceptions from our Rails application disappeared.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Redis" /><category term="AWS" /><category term="Python" /><category term="Elasticache" /><summary type="html">I was using a Amazon Elasticache cache.t2.medium Redis instance as a cache store for one of the Rails application. Over the time I observed that connections to Redis instance are increasing day by day and once it hit ~1500, the Rails application started throwing connection timeout exceptions: 1 Error connecting to Redis on redis-host:6379 (Redis::TimeoutError) On searching over internet, I found that the default parameter group has timeout value set to 0 which means, any connection that has been initialized to redis will be kept by redis even if the connection initialized by the client is down. Well the first thing I did was to create a new parameter group and set its value to a non-zero integer. However I couldn’t apply the parameter group changes to live production application and hence started looking for alternatives.</summary></entry><entry><title type="html">Sending asynchronous emails using Sidekiq on OpenShift</title><link href="https://pranavprakash.net/2015/02/09/sending-asynchronous-emails-using-sidekiq-on-openshift/" rel="alternate" type="text/html" title="Sending asynchronous emails using Sidekiq on OpenShift" /><published>2015-02-09T07:38:09+05:30</published><updated>2015-02-09T07:38:09+05:30</updated><id>https://pranavprakash.net/2015/02/09/sending-asynchronous-emails-using-sidekiq-on-openshift</id><content type="html" xml:base="https://pranavprakash.net/2015/02/09/sending-asynchronous-emails-using-sidekiq-on-openshift/">&lt;p&gt;If you need to send transactional emails from your Rails application, you should always send them asynchronously using a background job. If you send transactional emails synchronously, the user will see a loading page for the time rails connect to SMTP server and delivers your email which is about 2-3 seconds. This will result in a very bad user experience and it’s advisable to send emails using a background job.&lt;/p&gt;

&lt;p&gt;&lt;a href=&quot;http://sidekiq.org/&quot;&gt;Sidekiq&lt;/a&gt; advertises it self as simple, efficient background processing engine for Ruby. Sidekiq has dependency on &lt;a href=&quot;http://redis.io/&quot;&gt;Redis&lt;/a&gt; version &lt;code class=&quot;highlighter-rouge&quot;&gt;2.4&lt;/code&gt; or greater. Hence to setup Sidekiq on OpenShift, we have to setup Redis first. So let’s get started.&lt;/p&gt;

&lt;h2 id=&quot;setting-up-redis&quot;&gt;Setting up Redis&lt;/h2&gt;

&lt;p&gt;Redis cartridge for Openshift is available &lt;a href=&quot;https://github.com/smarterclayton/openshift-redis-cart&quot;&gt;here&lt;/a&gt;. To add this cartridge to existing Openshift application, issue following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;rhc add-cartridge http://cartreflect-claytondev.rhcloud.com/reflect?github&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;smarterclayton/openshift-redis-cart&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;!--more--&gt;

&lt;p&gt;If this command fails, inspect the log files generated at &lt;code class=&quot;highlighter-rouge&quot;&gt;$OPENSHIFT_REDIS_DIR/logs/redis.log&lt;/code&gt;.&lt;/p&gt;

&lt;h2 id=&quot;setting-up-sidekiq&quot;&gt;Setting up Sidekiq&lt;/h2&gt;

&lt;p&gt;The Sidekiq community &lt;a href=&quot;https://github.com/openshift-cartridges/openshift-origin-cartridge-sidekiq&quot;&gt;cartridge&lt;/a&gt; hasn’t been updated in a while and it doesn’t work with current OpenShift. Hence I forked the &lt;a href=&quot;https://github.com/pranavpr/openshift-origin-cartridge-sidekiq&quot;&gt;repository&lt;/a&gt; and fixed the issues. I also bumped the Sidekiq version to &lt;code class=&quot;highlighter-rouge&quot;&gt;3.3.1&lt;/code&gt; which was latest at that time. You can see the code changes &lt;a href=&quot;https://github.com/pranavpr/openshift-origin-cartridge-sidekiq/commit/5e820395e0f53970696d4357ab68d7de5b090d2c&quot;&gt;here&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;To add Sidekiq cartridge to application, issue following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;rhc add-cartridge http://cartreflect-claytondev.rhcloud.com/github/pranavpr/openshift-origin-cartridge-sidekiq &lt;span class=&quot;nt&quot;&gt;--app&lt;/span&gt; myapp&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Once the installation completes, you can access the monitoring interface at &lt;code class=&quot;highlighter-rouge&quot;&gt;https://YOUR_APP-NAMESPACE.rhcloud.com/sidekiq&lt;/code&gt;. Sidekiq will print the full URL with authentication after successful install.&lt;/p&gt;

&lt;h2 id=&quot;updating-gemfile&quot;&gt;Updating Gemfile&lt;/h2&gt;

&lt;p&gt;Add following line to your &lt;code class=&quot;highlighter-rouge&quot;&gt;Gemfile&lt;/code&gt; to add Sidekiq to your Rails application:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;n&quot;&gt;gem&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'sidekiq'&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Then do a &lt;code class=&quot;highlighter-rouge&quot;&gt;bundle install&lt;/code&gt; to finish installation of &lt;code class=&quot;highlighter-rouge&quot;&gt;sidekiq&lt;/code&gt; gem.&lt;/p&gt;

&lt;h2 id=&quot;send-asynchronous-emails-using-sidekiq&quot;&gt;Send asynchronous emails using Sidekiq&lt;/h2&gt;

&lt;p&gt;Delayed extensions of Sidekiq allows sending emails asynchronously with Action Mailer out of the box. It provides three methods &lt;em&gt;viz.&lt;/em&gt; &lt;code class=&quot;highlighter-rouge&quot;&gt;delay&lt;/code&gt;, &lt;code class=&quot;highlighter-rouge&quot;&gt;delay_for(interval)&lt;/code&gt; and &lt;code class=&quot;highlighter-rouge&quot;&gt;delay_until(time)&lt;/code&gt;, to send email asynchronously.&lt;/p&gt;

&lt;p&gt;Use &lt;code class=&quot;highlighter-rouge&quot;&gt;delay&lt;/code&gt; to deliver emails asynchronously, &lt;code class=&quot;highlighter-rouge&quot;&gt;delay_for(interval)&lt;/code&gt; or &lt;code class=&quot;highlighter-rouge&quot;&gt;delay_until(time)&lt;/code&gt; to deliver the email at some point in the future.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;no&quot;&gt;UserMailer&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;delay&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;welcome_email&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;vi&quot;&gt;@user&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;id&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;no&quot;&gt;UserMailer&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;delay_for&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;days&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;).&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;find_more_friends_email&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;vi&quot;&gt;@user&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;id&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;no&quot;&gt;UserMailer&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;delay_until&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;mi&quot;&gt;5&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;days&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;from_now&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;).&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;find_more_friends_email&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;vi&quot;&gt;@user&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;id&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h2 id=&quot;devise-emails&quot;&gt;Devise emails&lt;/h2&gt;

&lt;p&gt;&lt;code class=&quot;highlighter-rouge&quot;&gt;devise-async&lt;/code&gt; &lt;a href=&quot;https://github.com/mhfs/devise-async&quot;&gt;gem&lt;/a&gt; provides the ability to send Devise emails using Sidekiq. Add following line to the &lt;code class=&quot;highlighter-rouge&quot;&gt;Gemfile&lt;/code&gt;:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;n&quot;&gt;gem&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'devise-async'&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;And then execute &lt;code class=&quot;highlighter-rouge&quot;&gt;bundle install&lt;/code&gt; to finish installation of &lt;code class=&quot;highlighter-rouge&quot;&gt;devise-async&lt;/code&gt; gem.&lt;/p&gt;

&lt;p&gt;Now add &lt;code class=&quot;highlighter-rouge&quot;&gt;:async&lt;/code&gt; to the devise call in your model:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;k&quot;&gt;class&lt;/span&gt; &lt;span class=&quot;nc&quot;&gt;User&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;&amp;lt;&lt;/span&gt; &lt;span class=&quot;no&quot;&gt;ActiveRecord&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;no&quot;&gt;Base&lt;/span&gt;
  &lt;span class=&quot;n&quot;&gt;devise&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:database_authenticatable&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:async&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:confirmable&lt;/span&gt; &lt;span class=&quot;c1&quot;&gt;# etc ...&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Finally set your queuing backend to Sidekiq by creating &lt;code class=&quot;highlighter-rouge&quot;&gt;config/initializers/devise_async.rb&lt;/code&gt;:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;no&quot;&gt;Devise&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;no&quot;&gt;Async&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;backend&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:sidekiq&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h2 id=&quot;epilogue&quot;&gt;Epilogue&lt;/h2&gt;

&lt;p&gt;I issued a &lt;a href=&quot;https://github.com/openshift-cartridges/openshift-origin-cartridge-sidekiq/pull/4&quot;&gt;pull&lt;/a&gt; request to merge my changes to community cartridge and it got accepted. So you can also use the community &lt;a href=&quot;https://github.com/openshift-cartridges/openshift-origin-cartridge-sidekiq&quot;&gt;cartridge&lt;/a&gt; to add Sidekiq to your OpenShift application.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Sidekiq" /><category term="Email" /><category term="Ruby on Rails" /><category term="Devise" /><category term="OpenShift" /><summary type="html">If you need to send transactional emails from your Rails application, you should always send them asynchronously using a background job. If you send transactional emails synchronously, the user will see a loading page for the time rails connect to SMTP server and delivers your email which is about 2-3 seconds. This will result in a very bad user experience and it’s advisable to send emails using a background job. Sidekiq advertises it self as simple, efficient background processing engine for Ruby. Sidekiq has dependency on Redis version 2.4 or greater. Hence to setup Sidekiq on OpenShift, we have to setup Redis first. So let’s get started. Setting up Redis Redis cartridge for Openshift is available here. To add this cartridge to existing Openshift application, issue following command: 1 rhc add-cartridge http://cartreflect-claytondev.rhcloud.com/reflect?github=smarterclayton/openshift-redis-cart</summary></entry><entry><title type="html">Active Admin and Paperclip done right</title><link href="https://pranavprakash.net/2014/12/28/active-admin-and-paperclip-done-right/" rel="alternate" type="text/html" title="Active Admin and Paperclip done right" /><published>2014-12-28T06:39:07+05:30</published><updated>2014-12-28T06:39:07+05:30</updated><id>https://pranavprakash.net/2014/12/28/active-admin-and-paperclip-done-right</id><content type="html" xml:base="https://pranavprakash.net/2014/12/28/active-admin-and-paperclip-done-right/">&lt;p&gt;&lt;a href=&quot;https://github.com/activeadmin/activeadmin&quot;&gt;Active Admin&lt;/a&gt; is an administration framework for Ruby on Rails applications which helps in creating beautiful administration panels. &lt;a href=&quot;https://github.com/thoughtbot/paperclip&quot;&gt;Paperclip&lt;/a&gt; is a file attachment library for Active Record which makes management of files to models really easy.&lt;/p&gt;

&lt;p&gt;Recently while creating administration page for a model, in which Paperclip was being used for managing attachments, I oberved that Active Admin was not handling it properly. For example, the view page was showing as below:&lt;/p&gt;

&lt;div style=&quot;text-align: center&quot;&gt;&lt;img src=&quot;/assets/img/blog/view.png&quot; /&gt;&lt;/div&gt;

&lt;!--more--&gt;

&lt;p&gt;And the edit and new page was being shown as below:&lt;/p&gt;

&lt;div style=&quot;text-align: center&quot;&gt;&lt;img src=&quot;/assets/img/blog/edit.png&quot; /&gt;&lt;/div&gt;

&lt;p&gt;There was no way one could upload the images with above interface. Hence I scoured internet and found some nifty hacks. Let’s go through each of them:&lt;/p&gt;

&lt;h2 id=&quot;view-page&quot;&gt;View Page&lt;/h2&gt;

&lt;p&gt;Instead of showing attached image properties, I wanted to show the image itself. Also for other attached files types (like pdf and doc), I wanted to give an URL. Below code achieved the same:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;no&quot;&gt;ActiveAdmin&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;register&lt;/span&gt; &lt;span class=&quot;no&quot;&gt;Item&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
  &lt;span class=&quot;n&quot;&gt;show&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;|&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;recipe&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;|&lt;/span&gt;
    &lt;span class=&quot;n&quot;&gt;attributes_table&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
      &lt;span class=&quot;n&quot;&gt;row&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:instruction&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
        &lt;span class=&quot;n&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction?&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;?&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;link_to&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction_file_name&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;url&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;content_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:span&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;No instruction file yet&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
      &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
      &lt;span class=&quot;n&quot;&gt;row&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:photo&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
        &lt;span class=&quot;n&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;photo?&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;?&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;image_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;photo&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;url&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;height: &lt;/span&gt;&lt;span class=&quot;s1&quot;&gt;'100'&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;content_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:span&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;No photo yet&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
      &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
    &lt;span class=&quot;n&quot;&gt;active_admin_comments&lt;/span&gt;
  &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;This resulted in following:&lt;/p&gt;

&lt;div style=&quot;text-align: center&quot;&gt;&lt;img src=&quot;/assets/img/blog/show_new.png&quot; /&gt;&lt;/div&gt;

&lt;h2 id=&quot;new-and-edit-page&quot;&gt;New and Edit Page&lt;/h2&gt;

&lt;p&gt;I wanted to show an upload button to upload files. Also I wanted to show current file attached on Edit page so users can verify the attached content before modifying it. The code below achieved the same:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;no&quot;&gt;ActiveAdmin&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;register&lt;/span&gt; &lt;span class=&quot;no&quot;&gt;Item&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
  &lt;span class=&quot;n&quot;&gt;form&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:html&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;{&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:enctype&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;=&amp;gt;&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;multipart/form-data&quot;&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;}&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;|&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;|&lt;/span&gt;
    &lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;inputs&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;do&lt;/span&gt;
      &lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;input&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:instruction&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;hint: &lt;/span&gt;&lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction?&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;?&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;link_to&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction_file_name&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;instruction&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;url&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;content_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:span&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Upload PDF file&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
      &lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;input&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;:photo&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;hint: &lt;/span&gt;&lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;photo?&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;?&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;image_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;item&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;photo&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;url&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;ss&quot;&gt;height: &lt;/span&gt;&lt;span class=&quot;s1&quot;&gt;'100'&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;p&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;n&quot;&gt;content_tag&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:span&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Upload JPG/PNG/GIF image&quot;&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
    &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
    &lt;span class=&quot;n&quot;&gt;f&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;actions&lt;/span&gt;
  &lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;This resulted in following:&lt;/p&gt;

&lt;div style=&quot;text-align: center&quot;&gt;&lt;img src=&quot;/assets/img/blog/edit_new.png&quot; /&gt;&lt;/div&gt;

&lt;p&gt;Note that you have to set &lt;code class=&quot;highlighter-rouge&quot;&gt;enctype&lt;/code&gt; attribute in your form to &lt;code class=&quot;highlighter-rouge&quot;&gt;multipart/form-data&lt;/code&gt; to enable upload of files.&lt;/p&gt;

&lt;p&gt;And that’s it. I was pretty happy with the end result. Do let me know in comments if you happen to know any other trick.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Ruby on Rails" /><category term="Active Admin" /><category term="Paperclip" /><summary type="html">Active Admin is an administration framework for Ruby on Rails applications which helps in creating beautiful administration panels. Paperclip is a file attachment library for Active Record which makes management of files to models really easy. Recently while creating administration page for a model, in which Paperclip was being used for managing attachments, I oberved that Active Admin was not handling it properly. For example, the view page was showing as below:</summary></entry><entry><title type="html">Migrating Ruby on Rails app from Heroku to OpenShift</title><link href="https://pranavprakash.net/2014/11/08/migrating-ruby-on-rails-app-from-heroku-to-openshift/" rel="alternate" type="text/html" title="Migrating Ruby on Rails app from Heroku to OpenShift" /><published>2014-11-08T13:31:31+05:30</published><updated>2014-11-08T13:31:31+05:30</updated><id>https://pranavprakash.net/2014/11/08/migrating-ruby-on-rails-app-from-heroku-to-openshift</id><content type="html" xml:base="https://pranavprakash.net/2014/11/08/migrating-ruby-on-rails-app-from-heroku-to-openshift/">&lt;p&gt;&lt;a href=&quot;https://www.openshift.com&quot;&gt;OpenShift&lt;/a&gt; is Red Hat’s Platform-as-a-Service (PaaS) that allows developers to quickly develop, host, and scale applications in a cloud environment similar to &lt;a href=&quot;http://heroku.com&quot;&gt;Heroku&lt;/a&gt;. OpenShift also supports deploying of application with simple git push just like Heroku. OpenShift supports a variety of technologies through use of cartridges, including Java (Wildfly, JBossEAP, Tomcat), PHP, Node.js, Python, Perl, MySQL, PostgreSQL, MongoDB, Jenkins, Cron, and JBoss xPaaS Services (Fuse, BPM Suite, BRMS, Data Virtualization, Aerogear, and more).&lt;/p&gt;

&lt;h2 id=&quot;why-openshift&quot;&gt;Why OpenShift?&lt;/h2&gt;

&lt;p&gt;The free version of OpenShift, OpenShift Online, has many advantages over free tier of Heroku:&lt;/p&gt;

&lt;ul&gt;
  &lt;li&gt;If application is not accessed for an hour on Heroku, web dyno goes to sleep mode making the next request take up to 30 seconds to serve leading users to abandon the site visit. OpenShift’s idling time is 24 hours and, as of my personal experience, it takes around 10 seconds for next request to serve.&lt;/li&gt;
&lt;/ul&gt;

&lt;!--more--&gt;

&lt;ul&gt;
  &lt;li&gt;
    &lt;p&gt;The free database tier on Heroku allows only 10,000 rows to be stored. There is no such limitation in OpenShift.&lt;/p&gt;
  &lt;/li&gt;
  &lt;li&gt;
    &lt;p&gt;Heroku lacks persistent storage, its file system is read only and hence it doesn’t allow file upload from application, &lt;em&gt;e.g.&lt;/em&gt; user avatars. OpenShift provides 1GB of persistent storage with free tier which can be used to store the assets.&lt;/p&gt;
  &lt;/li&gt;
  &lt;li&gt;
    &lt;p&gt;OpenShift provides SSH access to control the application which is lacking in Heroku.&lt;/p&gt;
  &lt;/li&gt;
  &lt;li&gt;
    &lt;p&gt;OpenShift also provides port-forwarding feature which lets one connect to the database using locally installed client.&lt;/p&gt;
  &lt;/li&gt;
  &lt;li&gt;
    &lt;p&gt;OpenShift provides support for deployment hooks which can be used for running custom scripts before or after deployment.&lt;/p&gt;
  &lt;/li&gt;
&lt;/ul&gt;

&lt;h2 id=&quot;getting-started&quot;&gt;Getting Started&lt;/h2&gt;

&lt;p&gt;Sign up for a free account of OpenShift at &lt;code class=&quot;highlighter-rouge&quot;&gt;https://www.openshift.com&lt;/code&gt; and set up the &lt;code class=&quot;highlighter-rouge&quot;&gt;rhc&lt;/code&gt; client tool as documented &lt;a href=&quot;https://developers.openshift.com/en/getting-started-client-tools.html&quot;&gt;here&lt;/a&gt;.&lt;/p&gt;

&lt;h3 id=&quot;create-the-ruby-application&quot;&gt;Create the Ruby Application&lt;/h3&gt;

&lt;p&gt;Create the Ruby application by logging in to web console or via &lt;code class=&quot;highlighter-rouge&quot;&gt;rhc&lt;/code&gt; client tool by issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;rhc app create myapp ruby-2.0 postgresql-9.2&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Here myapp is the name of the application, and ruby-2.0 and postgresql-9.2 are the cartridges. Once the application is created, it will output the git repository path. Take a note of this path as this would be used to push the code to OpenShift.&lt;/p&gt;

&lt;h3 id=&quot;setup-git-remote&quot;&gt;Setup git remote&lt;/h3&gt;

&lt;p&gt;Navigate to the existing rails application directory and add the OpenShift remote as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;git remote add openshift ssh://...@myapp-mynamespace.rhcloud.com/~/git/myapp.git/&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now pull the remote changes by issuing following command:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;git pull openshift master&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;It will result a conflict in &lt;code class=&quot;highlighter-rouge&quot;&gt;config.ru&lt;/code&gt;. Just abandon the content created by OpenShift. Below is the default &lt;code class=&quot;highlighter-rouge&quot;&gt;config.ru&lt;/code&gt; file for the reference which is generated by rails:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c1&quot;&gt;# This file is used by Rack-based servers to start the application.&lt;/span&gt;

&lt;span class=&quot;nb&quot;&gt;require&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;no&quot;&gt;File&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;expand_path&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;s1&quot;&gt;'../config/environment'&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;,&lt;/span&gt;  &lt;span class=&quot;kp&quot;&gt;__FILE__&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;n&quot;&gt;run&lt;/span&gt; &lt;span class=&quot;no&quot;&gt;Rails&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;application&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h3 id=&quot;modify-gemfile-and-gitignore&quot;&gt;Modify Gemfile and .gitignore&lt;/h3&gt;

&lt;p&gt;OpenShift uses an old version of bundler and hence if ruby version is specified in Gemfile, as shown below, it breaks.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nb&quot;&gt;source&lt;/span&gt; &lt;span class=&quot;s1&quot;&gt;'https://rubygems.org'&lt;/span&gt;

ruby &lt;span class=&quot;s1&quot;&gt;'2.0.0'&lt;/span&gt; &lt;span class=&quot;c&quot;&gt;# Causes problem in OpenShift&lt;/span&gt;
 
gem &lt;span class=&quot;s1&quot;&gt;'rails'&lt;/span&gt;, &lt;span class=&quot;s1&quot;&gt;'4.0.8'&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Also, as recommended by OpenShift, using their Ruby mirror &lt;code class=&quot;highlighter-rouge&quot;&gt;http://mirror.ops.rhcloud.com/mirror/ruby/&lt;/code&gt; can quicken the installation of gems.&lt;/p&gt;

&lt;p&gt;And at last, if application was deployed on Heroku, it’s high chance that &lt;code class=&quot;highlighter-rouge&quot;&gt;database.yml&lt;/code&gt; was added to &lt;code class=&quot;highlighter-rouge&quot;&gt;.gitignore&lt;/code&gt; file as Heroku creates it’s own database.yml file during deployment. If it’s the case, remove the &lt;code class=&quot;highlighter-rouge&quot;&gt;database.yml&lt;/code&gt; line from the &lt;code class=&quot;highlighter-rouge&quot;&gt;.gitignore&lt;/code&gt; file.&lt;/p&gt;

&lt;h3 id=&quot;database-configuration&quot;&gt;Database configuration&lt;/h3&gt;

&lt;p&gt;Add following section in &lt;code class=&quot;highlighter-rouge&quot;&gt;database.yml&lt;/code&gt; file:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-yml&quot; data-lang=&quot;yml&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;na&quot;&gt;production&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;adapter&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;postgresql&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;encoding&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;unicode&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;pool&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;5&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;database&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&amp;lt;%=ENV['OPENSHIFT_APP_NAME']%&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;host&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&amp;lt;%=ENV['$OPENSHIFT_POSTGRESQL_DB_HOST']%&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;port&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&amp;lt;%=ENV['$OPENSHIFT_POSTGRESQL_DB_PORT']%&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;username&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&amp;lt;%=ENV['OPENSHIFT_POSTGRESQL_DB_USERNAME']%&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;na&quot;&gt;password&lt;/span&gt;&lt;span class=&quot;pi&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;s&quot;&gt;&amp;lt;%=ENV['OPENSHIFT_POSTGRESQL_DB_PASSWORD']%&amp;gt;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h3 id=&quot;deployment-hook&quot;&gt;Deployment hook&lt;/h3&gt;

&lt;p&gt;To run the database migrations, create a deployment hook by adding following lines to &lt;code class=&quot;highlighter-rouge&quot;&gt;.openshift/action_hooks/deploy&lt;/code&gt; file:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;c&quot;&gt;#!/bin/bash&lt;/span&gt;

&lt;span class=&quot;nb&quot;&gt;pushd&lt;/span&gt; &lt;span class=&quot;k&quot;&gt;${&lt;/span&gt;&lt;span class=&quot;nv&quot;&gt;OPENSHIFT_REPO_DIR&lt;/span&gt;&lt;span class=&quot;k&quot;&gt;}&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;&amp;gt;&lt;/span&gt; /dev/null
&lt;span class=&quot;nb&quot;&gt;echo&lt;/span&gt; &lt;span class=&quot;s2&quot;&gt;&quot;Running migrations&quot;&lt;/span&gt;
bundle &lt;span class=&quot;nb&quot;&gt;exec &lt;/span&gt;rake db:migrate &lt;span class=&quot;nv&quot;&gt;RAILS_ENV&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;s2&quot;&gt;&quot;production&quot;&lt;/span&gt;
&lt;span class=&quot;nb&quot;&gt;popd&lt;/span&gt; &lt;span class=&quot;o&quot;&gt;&amp;gt;&lt;/span&gt; /dev/null&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;In above script, &lt;code class=&quot;highlighter-rouge&quot;&gt;pushd&lt;/code&gt; will put the current working directory on the directory stack and switch to the directory path in the &lt;code class=&quot;highlighter-rouge&quot;&gt;${OPENSHIFT_REPO_DIR}&lt;/code&gt; environment variable and &lt;code class=&quot;highlighter-rouge&quot;&gt;popd&lt;/code&gt; will retrieve the directory from the stack and set it again as the current one. This is because bundle should be executed in the application’s directory, and then come back to the original directory, in order not to disrupt anything that may be executed afterwards.&lt;/p&gt;

&lt;h3 id=&quot;publishing-the-application&quot;&gt;Publishing the application&lt;/h3&gt;

&lt;p&gt;To publish the application on OpenShift, just issue the git push command as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;git push openshift master&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h3 id=&quot;import-database-from-heroku&quot;&gt;Import database from Heroku&lt;/h3&gt;

&lt;p&gt;Importing and exporting PostgresSQL databases on Heroku is well documented &lt;a href=&quot;https://devcenter.heroku.com/articles/heroku-postgres-import-export&quot;&gt;here&lt;/a&gt;. Firstly, we need to add pgbackup addon to our Heroku app:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;heroku addons:add pgbackups&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;To export the data from Heroku PostgresSQL database, create a new backup and use any number of download tools, such as curl or wget, to store the backup locally.&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;heroku pgbackups:capture
&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;curl &lt;span class=&quot;nt&quot;&gt;-o&lt;/span&gt; latest.dump &lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;heroku pgbackups:url&lt;span class=&quot;sb&quot;&gt;`&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;h3 id=&quot;restore-database-on-openshift&quot;&gt;Restore database on OpenShift&lt;/h3&gt;

&lt;p&gt;To restore the database on OpenShift, we need to know the value of &lt;code class=&quot;highlighter-rouge&quot;&gt;OPENSHIFT_POSTGRESQL_DB_USERNAME&lt;/code&gt; environment variable. Issue following commands to get this information:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;rhc ssh myapp
&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;env| &lt;span class=&quot;nb&quot;&gt;grep &lt;/span&gt;OPENSHIFT_POSTGRESQL_DB_USERNAME
&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;&lt;span class=&quot;nb&quot;&gt;exit&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Take a note of the output and start port forwarding as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;rhc port-forward myapp&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;It will give output similar to following:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-text&quot; data-lang=&quot;text&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;Checking available ports ... done
Forwarding ports ...

To connect to a service running on OpenShift, use the Local address

Service    Local                OpenShift
---------- --------------- ---- ----------------
httpd      127.0.0.1:8080   =&amp;gt;  x.x.x.x:8080
postgresql 127.0.0.1:5432   =&amp;gt;  x.x.x.x:5432
ruby       127.0.0.1:32036  =&amp;gt;  x.x.x.x:32036

Press CTRL-C to terminate port forwarding&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Now issue following commang to restore the database:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-bash&quot; data-lang=&quot;bash&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nv&quot;&gt;$ &lt;/span&gt;pg_restore –verbose –clean –no-acl –no-owner &lt;span class=&quot;nt&quot;&gt;-h&lt;/span&gt; localhost &lt;span class=&quot;nt&quot;&gt;-U&lt;/span&gt; OPENSHIFT_POSTGRESQL_DB_USERNAME &lt;span class=&quot;nt&quot;&gt;-d&lt;/span&gt; myapp latest.dump&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Replace &lt;code class=&quot;highlighter-rouge&quot;&gt;OPENSHIFT_POSTGRESQL_DB_USERNAME&lt;/code&gt; with the output from command at the start of this section.&lt;/p&gt;

&lt;p&gt;And that’s it. Now visit the application and make sure everything is working as expected.&lt;/p&gt;

&lt;h2 id=&quot;epilogue&quot;&gt;Epilogue&lt;/h2&gt;

&lt;p&gt;Heroku is a great platform for developing and deploying Rails application. I started looking for alternatives of Heroku because once I enabled &lt;code class=&quot;highlighter-rouge&quot;&gt;rails_admin&lt;/code&gt; gem in my application, Heroku was not able to serve the requests. I started getting intermittent application error. Once I migrated to OpenShift, these errors went away.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Ruby on Rails" /><category term="Heroku" /><category term="OpenShift" /><summary type="html">OpenShift is Red Hat’s Platform-as-a-Service (PaaS) that allows developers to quickly develop, host, and scale applications in a cloud environment similar to Heroku. OpenShift also supports deploying of application with simple git push just like Heroku. OpenShift supports a variety of technologies through use of cartridges, including Java (Wildfly, JBossEAP, Tomcat), PHP, Node.js, Python, Perl, MySQL, PostgreSQL, MongoDB, Jenkins, Cron, and JBoss xPaaS Services (Fuse, BPM Suite, BRMS, Data Virtualization, Aerogear, and more). Why OpenShift? The free version of OpenShift, OpenShift Online, has many advantages over free tier of Heroku: If application is not accessed for an hour on Heroku, web dyno goes to sleep mode making the next request take up to 30 seconds to serve leading users to abandon the site visit. OpenShift’s idling time is 24 hours and, as of my personal experience, it takes around 10 seconds for next request to serve.</summary></entry><entry><title type="html">Navigation menu in Ruby on Rails</title><link href="https://pranavprakash.net/2014/10/25/navigation-menu-in-ruby-on-rails/" rel="alternate" type="text/html" title="Navigation menu in Ruby on Rails" /><published>2014-10-25T17:20:01+05:30</published><updated>2014-10-25T17:20:01+05:30</updated><id>https://pranavprakash.net/2014/10/25/navigation-menu-in-ruby-on-rails</id><content type="html" xml:base="https://pranavprakash.net/2014/10/25/navigation-menu-in-ruby-on-rails/">&lt;p&gt;Recently while working on a Rails project, I came across following markup for navigation:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-html&quot; data-lang=&quot;html&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nt&quot;&gt;&amp;lt;ul&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;sidebar-menu&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;treeview active&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;a&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;href=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;#&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;span&amp;gt;&lt;/span&gt;Category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;/a&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;ul&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;treeview-menu&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;active&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
	      &lt;span class=&quot;nt&quot;&gt;&amp;lt;a&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;href=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;#&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
	      	&lt;span class=&quot;nt&quot;&gt;&amp;lt;span&amp;gt;&lt;/span&gt;Add Category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;
	      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/a&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&amp;gt;&lt;/span&gt;
	      &lt;span class=&quot;nt&quot;&gt;&amp;lt;a&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;href=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;#&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
	      	&lt;span class=&quot;nt&quot;&gt;&amp;lt;span&amp;gt;&lt;/span&gt;Update Category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;
	      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/a&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;/ul&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
&lt;span class=&quot;nt&quot;&gt;&amp;lt;/ul&amp;gt;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;!--more--&gt;

&lt;p&gt;Note that in above markup, for each active menu item, there is a parent active element. For example, when “Add Category” (line number 7) is active, it’s parent element “Category” is also active (line number 2).&lt;/p&gt;

&lt;p&gt;To incorporate this in Rails, I decided to make parent element as controller and child elements as actions for that controller. Thus for above markup, I created a categories controller and added action new, create, edit and update to it. Then I created two helper functions as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;k&quot;&gt;module&lt;/span&gt; &lt;span class=&quot;nn&quot;&gt;ApplicationHelper&lt;/span&gt;
	&lt;span class=&quot;k&quot;&gt;def&lt;/span&gt; &lt;span class=&quot;nf&quot;&gt;controller?&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;*&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;controller&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
		&lt;span class=&quot;n&quot;&gt;controller&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;include?&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;params&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:controller&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;])&lt;/span&gt;
	&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;

	&lt;span class=&quot;k&quot;&gt;def&lt;/span&gt; &lt;span class=&quot;nf&quot;&gt;action?&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;o&quot;&gt;*&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;action&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;)&lt;/span&gt;
		&lt;span class=&quot;n&quot;&gt;action&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;nf&quot;&gt;include?&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;n&quot;&gt;params&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;[&lt;/span&gt;&lt;span class=&quot;ss&quot;&gt;:action&lt;/span&gt;&lt;span class=&quot;p&quot;&gt;])&lt;/span&gt;
	&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;
&lt;span class=&quot;k&quot;&gt;end&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;Then I created the menu layout as below:&lt;/p&gt;

&lt;figure class=&quot;highlight&quot;&gt;&lt;pre&gt;&lt;code class=&quot;language-html&quot; data-lang=&quot;html&quot;&gt;&lt;table class=&quot;rouge-table&quot;&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td class=&quot;gutter gl&quot;&gt;&lt;pre class=&quot;lineno&quot;&gt;1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
&lt;/pre&gt;&lt;/td&gt;&lt;td class=&quot;code&quot;&gt;&lt;pre&gt;&lt;span class=&quot;nt&quot;&gt;&amp;lt;ul&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;sidebar-menu&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;treeview &amp;lt;%= 'active' if controller?('categories') %&amp;gt;&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;a&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;href=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;#&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;span&amp;gt;&lt;/span&gt;Category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;/a&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;ul&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;treeview-menu&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;&amp;lt;%= 'active' if controller?('categories') &amp;amp;&amp;amp; action?('new', 'create') %&amp;gt;&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;%=&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;link_to&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;na&quot;&gt;raw&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;('&amp;lt;&lt;/span&gt;&lt;span class=&quot;na&quot;&gt;span&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;Add category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;'), new_categories_path) %&amp;gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;li&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;class=&lt;/span&gt;&lt;span class=&quot;s&quot;&gt;&quot;&amp;lt;%= 'active' if controller?('categories') &amp;amp;&amp;amp; action?('update', 'edit') %&amp;gt;&quot;&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;%=&lt;/span&gt; &lt;span class=&quot;na&quot;&gt;link_to&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;na&quot;&gt;raw&lt;/span&gt;&lt;span class=&quot;err&quot;&gt;('&amp;lt;&lt;/span&gt;&lt;span class=&quot;na&quot;&gt;span&lt;/span&gt;&lt;span class=&quot;nt&quot;&gt;&amp;gt;&lt;/span&gt;Modify category&lt;span class=&quot;nt&quot;&gt;&amp;lt;/span&amp;gt;&lt;/span&gt;'), edit_categories_path) %&amp;gt;
      &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
    &lt;span class=&quot;nt&quot;&gt;&amp;lt;/ul&amp;gt;&lt;/span&gt;
  &lt;span class=&quot;nt&quot;&gt;&amp;lt;/li&amp;gt;&lt;/span&gt;
&lt;span class=&quot;nt&quot;&gt;&amp;lt;/ul&amp;gt;&lt;/span&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/figure&gt;

&lt;p&gt;This layout perfectly synchronized the navigation links with pages.&lt;/p&gt;

&lt;p&gt;I found this as a neat way of making navigation in my rails project. You can also use &lt;code class=&quot;highlighter-rouge&quot;&gt;current_page?&lt;/code&gt; (&lt;a href=&quot;http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-current_page-3F&quot;&gt;documentation&lt;/a&gt;) method to accomplish the same. There are many gems also available out there to build the navigation in Rails. You can have a look at them &lt;a href=&quot;https://www.ruby-toolbox.com/categories/rails_menu_builders&quot;&gt;here&lt;/a&gt;.&lt;/p&gt;</content><author><name>Pranav Prakash</name><email>pranav@pranavprakash.net</email></author><category term="Ruby on Rails" /><summary type="html">Recently while working on a Rails project, I came across following markup for navigation: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 &amp;lt;ul class=&quot;sidebar-menu&quot;&amp;gt; &amp;lt;li class=&quot;treeview active&quot;&amp;gt; &amp;lt;a href=&quot;#&quot;&amp;gt; &amp;lt;span&amp;gt;Category&amp;lt;/span&amp;gt; &amp;lt;/a&amp;gt; &amp;lt;ul class=&quot;treeview-menu&quot;&amp;gt; &amp;lt;li class=&quot;active&quot;&amp;gt; &amp;lt;a href=&quot;#&quot;&amp;gt; &amp;lt;span&amp;gt;Add Category&amp;lt;/span&amp;gt; &amp;lt;/a&amp;gt; &amp;lt;/li&amp;gt; &amp;lt;li&amp;gt; &amp;lt;a href=&quot;#&quot;&amp;gt; &amp;lt;span&amp;gt;Update Category&amp;lt;/span&amp;gt; &amp;lt;/a&amp;gt; &amp;lt;/li&amp;gt; &amp;lt;/ul&amp;gt; &amp;lt;/li&amp;gt; &amp;lt;/ul&amp;gt;</summary></entry></feed>