Http.__init__ allow proxy_info to be None (#9)

Fix #8

httplib2shim/__init__.py

@@ -20,6 +20,7 @@
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+import collections
 import errno
 import socket
 import ssl
@@ -41,6 +42,8 @@ def _default_make_pool(http, proxy_info):
 
     cert_reqs = 'CERT_REQUIRED' if http.ca_certs and not ssl_disabled else None
 
+    if isinstance(proxy_info, collections.Callable):
+        proxy_info = proxy_info()
     if proxy_info:
         if proxy_info.proxy_user and proxy_info.proxy_pass:
             proxy_url = 'http://{}:{}@{}:{}/'.format(
@@ -111,7 +114,7 @@ def __init__(self, cache=None, timeout=None,
             disable_ssl_certificate_validation=disable_ssl)
 
         if not pool:
-            pool = self._make_pool(proxy_info=proxy_info())
+            pool = self._make_pool(proxy_info=proxy_info)
 
         self.pool = pool
 

httplib2shim/test/httplib2_test.py

@@ -39,6 +39,7 @@
 import httplib2shim
 import six
 from six.moves.urllib import parse as urllib_parse
+import urllib3
 
 
 __author__ = "Joe Gregorio (joe@bitworking.org)"
@@ -1880,3 +1881,19 @@ def test_from_env_none(self):
         os.environ.clear()
         pi = httplib2.proxy_info_from_environment()
         self.assertEqual(pi, None)
+
+
+class HttpShimProxyPoolTest(unittest.TestCase):
+
+    def test_none(self):
+        http = httplib2.Http(proxy_info=None)
+        self.assertIsInstance(http.pool, urllib3.PoolManager)
+        http = httplib2.Http(proxy_info=lambda: None)
+        self.assertIsInstance(http.pool, urllib3.PoolManager)
+
+    def test_instance_and_callable(self):
+        proxy_info = httplib2.proxy_info_from_url('http://myproxy.example.com')
+        http = httplib2.Http(proxy_info=proxy_info)
+        self.assertIsInstance(http.pool, urllib3.ProxyManager)
+        http = httplib2.Http(proxy_info=lambda: proxy_info)
+        self.assertIsInstance(http.pool, urllib3.ProxyManager)