Chris Alexander

On Engineering

A Webserver in 50 lines of code

15th April, 2010

I’ve been playing with python over the past few days, and have grown quite attached to it.

A number of features, such as ranges and the separation of lists and dictionaries, have endeared the language and it makes a lot of sense.

I thought I would have a bit of fun with it, and see how hard it was to write a web server. This may seem like a big step, but when you consider that reading from a URL is as simple as reading from a file in python, it is not a daunting task.

I managed to find a tutorial online, and after a bit of tinkering I got out a web server that responds to HTTP GET requests and serves files (not dynamically!) in just 50 lines of code (including my somewhat liberal whitespace - this indentation thing is taking a bit of getting used to).

Here’s my server in 50 lines of code:

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#!/usr/bin/python

#
# A simple web server
#

import sys, string, cgi, time
from os import curdir, sep
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer

class MyServer(BaseHTTPRequestHandler):

  def ca_serve_file(self):
    try:
      f = open(curdir + sep + self.path, 'r')

      self.send_response(200)
      self.send_header('Content-type', 'text/html')
      self.end_headers()
      self.wfile.write(f.read())
      f.close()

    except IOError:
      self.send_error(404, 'File not found: %s' % self.path)

  def do_GET(self):
    try:
      if self.path == '/':
        self.path = 'index.html'

      self.ca_serve_file()

      return

    except IOError:
      self.send_error(404, 'File not found: %s' % self.path)

def main():
  try:
    server = HTTPServer(('',8080), MyServer)
    print 'Started HTTP server'
    server.serve_forever()
  except KeyboardInterrupt:
    print 'Shutting down...'
    server.socket.close()

if __name__ == '__main__':
  main()

© 2022 Chris Alexander