Rewrite AbstractHTTPHandler to use modern httplib interface.

The chief benefit of this change is that requests will now use
HTTP/1.1 instead of HTTP/1.0.  Bump the module version number as part
of the change.

There are two possible incompatibilities that we'll need to watch out
for when we get to an alpha release.  We may get a different class of
exceptions out of httplib, and the do_open() method changed its
signature.  The latter is only important if anyone actually subclasses
AbstractHTTPHandler.

Lib/urllib2.py

@@ -120,7 +120,7 @@ from urllib import unwrap, unquote, splittype, splithost, \
 # support for FileHandler, proxies via environment variables
 from urllib import localhost, url2pathname, getproxies
 
-__version__ = "2.1"
+__version__ = "2.4"
 
 _opener = None
 def urlopen(url, data=None):
@@ -207,6 +207,8 @@ class Request:
         else:
             return "GET"
 
+    # XXX these helper methods are lame
+
     def add_data(self, data):
         self.data = data
 
@@ -936,10 +938,16 @@ class AbstractHTTPHandler(BaseHandler):
 
         return request
 
-    # XXX Should rewrite do_open() to use the new httplib interface,
-    # would be a little simpler.
-
     def do_open(self, http_class, req):
+        """Return an addinfourl object for the request, using http_class.
+
+        http_class must implement the HTTPConnection API from httplib.
+        The addinfourl return value is a file-like object.  It also
+        has methods and attributes including:
+            - info(): return a mimetools.Message object for the headers
+            - geturl(): return the original request URL
+            - code: HTTP status code
+        """
         host = req.get_host()
         if not host:
             raise URLError('no host given')
@@ -947,33 +955,26 @@ class AbstractHTTPHandler(BaseHandler):
         h = http_class(host) # will parse host:port
         h.set_debuglevel(self._debuglevel)
 
-        h.putrequest(req.get_method(), req.get_selector())
-        for k, v in req.headers.items():
-            h.putheader(k, v)
-        for k, v in req.unredirected_hdrs.items():
-            h.putheader(k, v)
-        # httplib will attempt to connect() here.  be prepared
-        # to convert a socket error to a URLError.
+        headers = dict(req.headers)
+        headers.update(req.unredirected_hdrs)
         try:
-            h.endheaders()
-        except socket.error, err:
+            h.request(req.get_method(), req.get_selector(), req.data, headers)
+            r = h.getresponse()
+        except socket.error, err: # XXX what error?
             raise URLError(err)
-        if req.has_data():
-            h.send(req.get_data())
-
-        code, msg, hdrs = h.getreply()
-        fp = h.getfile()
-        response = addinfourl(fp, hdrs, req.get_full_url())
-        # XXXX should these be methods, for uniformity with rest of interface?
-        response.code = code
-        response.msg = msg
-        return response
+
+        # Pick apart the HTTPResponse object to get the various pieces
+        # of the 
+        resp = addinfourl(r.fp, r.msg, req.get_full_url())
+        resp.code = r.status
+        resp.msg = r.reason
+        return resp
 
 
 class HTTPHandler(AbstractHTTPHandler):
 
     def http_open(self, req):
-        return self.do_open(httplib.HTTP, req)
+        return self.do_open(httplib.HTTPConnection, req)
 
     http_request = AbstractHTTPHandler.do_request
 
@@ -981,7 +982,7 @@ if hasattr(httplib, 'HTTPS'):
     class HTTPSHandler(AbstractHTTPHandler):
 
         def https_open(self, req):
-            return self.do_open(httplib.HTTPS, req)
+            return self.do_open(httplib.HTTPSConnection, req)
 
         https_request = AbstractHTTPHandler.do_request