proxy support: degrade gracefully when socket.socket is unavailable

This should allow httplib2 to continue to work even on platforms like
appengine where the socket module exists but has no socket attribute.

4 files changed, 38 insertions, 2 deletions

diff --git a/python2/httplib2/__init__.py b/python2/httplib2/__init__.py
index c886049..567e24e 100644
--- a/python2/httplib2/__init__.py
+++ b/python2/httplib2/__init__.py
@@ -54,7 +54,10 @@ import hmac
 from gettext import gettext as _
 import socket
 
-from httplib2 import socks
+try:
+    from httplib2 import socks
+except ImportError:
+    socks = None
 
 # Build the appropriate socket wrapper for ssl
 try:
@@ -80,7 +83,7 @@ def has_timeout(timeout): # python 2.6
 __all__ = ['Http', 'Response', 'ProxyInfo', 'HttpLib2Error',
   'RedirectMissingLocation', 'RedirectLimit', 'FailedToDecompressContent',
   'UnimplementedDigestAuthOptionError', 'UnimplementedHmacDigestAuthOptionError',
-  'debuglevel']
+  'debuglevel', 'ProxiesUnavailableError']
 
 
 # The httplib debug level, set to a non-zero value to get debug output
@@ -122,6 +125,7 @@ class UnimplementedHmacDigestAuthOptionError(HttpLib2ErrorWithResponse): pass
 
 class RelativeURIError(HttpLib2Error): pass
 class ServerNotFoundError(HttpLib2Error): pass
+class ProxiesUnavailableError(HttpLib2Error): pass
 
 # Open Items:
 # -----------
@@ -718,6 +722,9 @@ class HTTPConnectionWithTimeout(httplib.HTTPConnection):
     def connect(self):
         """Connect to the host and port specified in __init__."""
         # Mostly verbatim from httplib.py.
+        if self.proxy_info and socks is None:
+            raise ProxiesUnavailableError(
+                'Proxy support missing but proxy use was requested!')
         msg = "getaddrinfo returns an empty list"
         for res in socket.getaddrinfo(self.host, self.port, 0,
                 socket.SOCK_STREAM):
diff --git a/python2/httplib2/socks.py b/python2/httplib2/socks.py
index 2bddd7a..b65fb38 100644
--- a/python2/httplib2/socks.py
+++ b/python2/httplib2/socks.py
@@ -41,6 +41,10 @@ mainly to merge bug fixes found in Sourceforge
 """
 
 import socket
+
+if getattr(socket, 'socket', None) is None:
+    raise ImportError('socket.socket missing, proxy support unusable')
+
 import struct
 import sys
 
diff --git a/python2/httplib2/test/brokensocket/socket.py b/python2/httplib2/test/brokensocket/socket.py
new file mode 100644
index 0000000..ff7c0b7
--- /dev/null
+++ b/python2/httplib2/test/brokensocket/socket.py
@@ -0,0 +1 @@
+from realsocket import gaierror, error, getaddrinfo, SOCK_STREAM
diff --git a/python2/httplib2/test/test_no_socket.py b/python2/httplib2/test/test_no_socket.py
new file mode 100644
index 0000000..66ba056
--- /dev/null
+++ b/python2/httplib2/test/test_no_socket.py
@@ -0,0 +1,24 @@
+"""Tests for httplib2 when the socket module is missing.
+
+This helps ensure compatibility with environments such as AppEngine.
+"""
+import os
+import sys
+import unittest
+
+import httplib2
+
+class MissingSocketTest(unittest.TestCase):
+    def setUp(self):
+        self._oldsocks = httplib2.socks
+        httplib2.socks = None
+
+    def tearDown(self):
+        httplib2.socks = self._oldsocks
+
+    def testProxyDisabled(self):
+        proxy_info = httplib2.ProxyInfo('blah',
+                                        'localhost', 0)
+        client = httplib2.Http(proxy_info=proxy_info)
+        self.assertRaises(httplib2.ProxiesUnavailableError,
+                          client.request, 'http://localhost:-1/')