Does Python have a module for parsing HTTP requests and responses?

Question

httplib (now http.client) and friends all have conn.getresponse() and an HTTPResponse class, but the server-side operations of conn.getrequest() and an HTTPRequest class seem to be lacking.

I understand that BaseHTTPServer and BaseHTTPRequestHandler can perform this functionality, but they don't expose these methods for use outside of the module.

Essentially what I want is BaseHTTPRequestHandler#parse_request to be a static method that returns an HTTPRequest object rather than populating member variables.

Answer 1

Jeff, to enable parsing I create a small nine-line subclass of the base HTTP request handler:

from BaseHTTPServer import BaseHTTPRequestHandler from StringIO import StringIO  class HTTPRequest(BaseHTTPRequestHandler):     def __init__(self, request_text):         self.rfile = StringIO(request_text)         self.raw_requestline = self.rfile.readline()         self.error_code = self.error_message = None         self.parse_request()      def send_error(self, code, message):         self.error_code = code         self.error_message = message 

You can now take a string with the text of an HTTP request inside and parse it by instantiating this class:

# Simply instantiate this class with the request text  request = HTTPRequest(request_text)  print request.error_code       # None  (check this first) print request.command          # "GET" print request.path             # "/who/ken/trust.html" print request.request_version  # "HTTP/1.1" print len(request.headers)     # 3 print request.headers.keys()   # ['accept-charset', 'host', 'accept'] print request.headers['host']  # "cm.bell-labs.com"  # Parsing can result in an error code and message  request = HTTPRequest('GET\r\nHeader: Value\r\n\r\n')  print request.error_code     # 400 print request.error_message  # "Bad request syntax ('GET')" 

Answer 2

For server-side processing you want to look at something like wsgiref.

The WSGI standard parses the request into a simple dictionary with all of the relevant headers and elements.