python - CGI FieldStorage will only return None?

Question

I put together the following script that i would like to return the "Hello World !('192.168.0.162', 48344)bob" when in my browser i have

server:8081/?first_name=bob

however when i run the following program it returns Hello World !('192.168.0.162', 48344)None

#!/usr/bin/python
from BaseHTTPServer import BaseHTTPRequestHandler,HTTPServer
import cgi, cgitb
x = "1"
PORT_NUMBER = 8081
cgitb.enable()

#This class will handles any incoming request from
#the browser 
class myHandler(BaseHTTPRequestHandler):

    #Handler for the GET requests
    def do_GET(self):
        form = cgi.FieldStorage() 
        first_name = form.getvalue('first_name')
        self.send_response(200)
        self.send_header('Content-type','text/html')
        self.end_headers()
        # Send the html message
        self.wfile.write("Hello World !")
        self.wfile.write(self.client_address)
        self.wfile.write(first_name)
        return

try:
    #Create a web server and define the handler to manage the
    #incoming request
    server = HTTPServer(('', PORT_NUMBER), myHandler)
    print 'Started httpserver on port ' , PORT_NUMBER

    #Wait forever for incoming htto requests
    server.serve_forever()

except KeyboardInterrupt:
    print '^C received, shutting down the web server'
    server.socket.close()

What is wrong?

Answer 1

The issue is using cgi.FieldStorage() which is intended to be used in a CGI script. You have to parse the query string yourself in your do_GET() method. You could use certain parts of the cgi module to do that (and probably the best approach in a do_POST() handler), but for do_GET() the more typical approach is something like this:

import urlparse

class myHandler(BaseHTTPRequestHandler):

    #Handler for the GET requests
    def do_GET(self):
        o = urlparse.urlparse(self.path)
        form = urlparse.parse_qs(o.query)

See urlparse.urlparse.

See urlparse.parse_qs.