example-heroku-python/BookmarkServer.py at master · abdennour/example-heroku-python · GitHub

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
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
#!/usr/bin/env python3
#
# A *bookmark server* or URI shortener.

import http.server
import requests
import os
from urllib.parse import unquote, parse_qs
import threading
from socketserver import ThreadingMixIn

memory = {}

form = '''<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name=viewport content="width=device-width, initial-scale=1">
    <meta name="robots" content="abdennour,nanodegree,python,fullstack,udacity,toumi" />
    <title>Shortner links</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">

  </head>
  <body>
    <main class="container mt-5">
       <div>
            <form method="POST">
                <section>
                   <h2>Shortener</h2>
                   <div class="form-group">
                     <label for="longuri">Long URI: </label>
                     <input name="longuri" id="longuri" class="form-control" placeholder="Your long Link http://...">
                   </div>
                   <div class="form-group">
                     <label for="shortname">Short name:</label>
                     <input name="shortname" id="shortname" class="form-control" placeholder="my-link">
                   </div>
                   <button type="submit" class="btn btn-primary">Save it!</button>

                </section>
             </form>
             <hr>
             <section>
               <h2>URIs I know about</h2>
               <pre>
                 {}
               </pre>
             </section>
       </div>
    </main>
  </body>
</html>

'''


def CheckURI(uri, timeout=5):
    '''Check whether this URI is reachable, i.e. does it return a 200 OK?

    This function returns True if a GET request to uri returns a 200 OK, and
    False if that GET request returns any other response, or doesn't return
    (i.e. times out).
    '''
    try:
        r = requests.get(uri, timeout=timeout)
        # If the GET request returns, was it a 200 OK?
        return r.status_code == 200
    except requests.RequestException:
        # If the GET request raised an exception, it's not OK.
        return False

class ThreadHTTPServer(ThreadingMixIn, http.server.HTTPServer):
    "This is an HTTPServer that supports thread-based concurrency."

class Shortener(http.server.BaseHTTPRequestHandler):
    def do_GET(self):
        # A GET request will either be for / (the root path) or for /some-name.
        # Strip off the / and we have either empty string or a name.
        name = unquote(self.path[1:])

        if name:
            if name in memory:
                # We know that name! Send a redirect to it.
                self.send_response(303)
                self.send_header('Location', memory[name])
                self.end_headers()
            else:
                # We don't know that name! Send a 404 error.
                self.send_response(404)
                self.send_header('Content-type', 'text/plain; charset=utf-8')
                self.end_headers()
                self.wfile.write("I don't know '{}'.".format(name).encode())
        else:
            # Root path. Send the form.
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            # List the known associations in the form.
            known = "\n".join("{} : {}".format(key, memory[key])
                              for key in sorted(memory.keys()))
            self.wfile.write(form.format(known).encode())

    def do_POST(self):
        # Decode the form data.
        length = int(self.headers.get('Content-length', 0))
        body = self.rfile.read(length).decode()
        params = parse_qs(body)
        longuri = params["longuri"][0]
        shortname = params["shortname"][0]

        if CheckURI(longuri):
            # This URI is good!  Remember it under the specified name.
            memory[shortname] = longuri

            # Serve a redirect to the form.
            self.send_response(303)
            self.send_header('Location', '/')
            self.end_headers()
        else:
            # Didn't successfully fetch the long URI.
            self.send_response(404)
            self.send_header('Content-type', 'text/plain; charset=utf-8')
            self.end_headers()
            self.wfile.write(
                "Couldn't fetch URI '{}'. Sorry!".format(longuri).encode())

if __name__ == '__main__':
    server_address = ('', int(os.environ.get('PORT', '8000')))
    httpd = ThreadHTTPServer(server_address, Shortener)
    httpd.serve_forever()