Towards a standard access mechanism for URLs.

Lib/httplib.py

@@ -0,0 +1,129 @@
+# HTTP client class
+#
+# See the following document for a tentative protocol description:
+#     Hypertext Transfer Protocol (HTTP)        Tim Berners-Lee, CERN
+#     Internet Draft                                       5 Nov 1993
+#     draft-ietf-iiir-http-00.txt                  Expires 5 May 1994
+#
+# Example:
+#
+# >>> from httplib import HTTP
+# >>> h = HTTP('www.cwi.nl')
+# >>> h.putreqest('GET', '/index.html')
+# >>> h.putheader('Accept', 'text/html')
+# >>> h.putheader('Accept', 'text/plain')
+# >>> errcode, errmsg, headers = h.getreply()
+# >>> if errcode == 200:
+# ...     f = h.getfile()
+# ...     print f.read() # Print the raw HTML
+# ...
+# <TITLE>Home Page of CWI, Amsterdam</TITLE>
+# [...many more lines...]
+# >>>
+#
+# Note that an HTTP object is used for a single request -- to issue a
+# second request to the same server, you create a new HTTP object.
+# (This is in accordance with the protocol, which uses a new TCP
+# connection for each request.)
+
+
+import os
+import socket
+import string
+import regex
+import regsub
+import rfc822
+
+HTTP_VERSION = 'HTTP/1.0'
+HTTP_PORT = 80
+
+replypat = regsub.gsub('\\.', '\\\\.', HTTP_VERSION) + \
+	  '[ \t]+\([0-9][0-9][0-9]\)\(.*\)'
+replyprog = regex.compile(replypat)
+
+class HTTP:
+
+	def __init__(self, *args):
+		self.debuglevel = 0
+		if args: apply(self.connect, args)
+
+	def set_debuglevel(self, debuglevel):
+		self.debuglevel = debuglevel
+
+	def connect(self, host, *args):
+		if args:
+			if args[1:]: raise TypeError, 'too many args'
+			port = args[0]
+		else:
+			i = string.find(host, ':')
+			if i >= 0:
+				host, port = host[:i], host[i+1:]
+				try: port = string.atoi(port)
+				except string.atoi_error: port = None
+		if not port: port = HTTP_PORT
+		self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+		if self.debuglevel > 0: print 'connect:', (host, port)
+		self.sock.connect(host, port)
+
+	def send(self, str):
+		if self.debuglevel > 0: print 'send:', `str`
+		self.sock.send(str)
+
+	def putrequest(self, request, selector):
+		str = '%s %s %s\r\n' % (request, selector, HTTP_VERSION)
+		self.send(str)
+
+	def putheader(self, header, *args):
+		str = '%s: %s\r\n' % (header, string.joinfields(args,'\r\n\t'))
+		self.send(str)
+
+	def endheaders(self):
+		self.send('\r\n')
+
+	def endrequest(self):
+		if self.debuglevel > 0: print 'shutdown: 1'
+		self.sock.shutdown(1)
+
+	def getreply(self):
+		self.endrequest()
+		self.file = self.sock.makefile('r')
+		line = self.file.readline()
+		if self.debuglevel > 0: print 'reply:', `line`
+		if replyprog.match(line) < 0:
+			self.headers = None
+			return -1, line, self.headers
+		errcode, errmsg = replyprog.group(1, 2)
+		errcode = string.atoi(errcode)
+		errmsg = string.strip(errmsg)
+		self.headers = rfc822.Message(self.file)
+		return errcode, errmsg, self.headers
+
+	def getfile(self):
+		return self.file
+
+
+def test():
+	import sys
+	import getopt
+	opts, args = getopt.getopt(sys.argv[1:], 'd')
+	dl = 0
+	for o, a in opts:
+		if o == '-d': dl = dl + 1
+	host = 'www.cwi.nl:80'
+	selector = '/index.html'
+	if args[0:]: host = args[0]
+	if args[1:]: selector = args[1]
+	h = HTTP()
+	h.set_debuglevel(dl)
+	h.connect(host)
+	h.putrequest('GET', selector)
+	errcode, errmsg, headers = h.getreply()
+	print 'errcode =', errcode
+	print 'headers =', headers
+	print 'errmsg  =', errmsg
+	if headers:
+		for header in headers.headers: print string.strip(header)
+	print h.getfile().read()
+
+if __name__ == '__main__':
+	test()