added reqbody, tlm, and cors

Author: taytestokes

README.md

@@ -0,0 +1,57 @@
+# Node Two
+
+In this lecture we talk about Top Level Middleware, Using Postman, and using Axios in our API.
+
+## Top Level Middleware
+
+`Top Level Middleware` is the term we use to refer to some logic that will be executed upon every request that is made to our API.
+
+We can set up that logic inside of the built method `.use()` that comes from the object that is return from invoking `express`.
+
+```javascript
+app.use(/* some function to execute here */);
+```
+
+## Req Body
+
+Sometimes we need to send some complex data to our API. Using the `req.query` or `req.params` just might not be suffuciant enough to use to send this data. This is where the `body` comes into play.
+
+`req.body` is the object we can use to receive the complex data. However, the data that comes from the body of the request is received as `JSON` so we need to parse it into a Javascript Object.
+
+We can do this by using a special function from `express` called `express.json()`. This function will parse the JSON that comes as the `body` from the request and turn it into a useable object for us.
+
+We want to invoke this function as `Top Level Middleware` so that it is invoked upon every connection made to our API.
+
+We will pass it into our `app.use()` function to run it as top level middleware.
+
+```javascript
+app.use(express.json());
+```
+
+## CORS
+
+CORS stands for `Cross Origin Resource Sharing`. This is a security protocol that we can use to safely allow other origins talk to our origin. This means that we can make a request from one server to another server.
+
+We first need to install `CORS` as a dependency for our project. In the terminal, run:
+
+```bash
+$ npm install cors
+```
+
+Then require it at the top of the `index.js` file for our API.
+
+```javascript
+const cors = require('cors`)
+```
+
+Then we need this function to be invoked as top level middleware.
+
+```javascript
+app.use(cors())
+```
+
+Now your API is setup to follow the `CORS` protocol.
+
+## Postman
+
+`Postman` is a suite that we can use to act as a `client` to interact with the `API` that we build.