[feat] Make it optional to have a dedicated pool

As @meskio pointed out, some cases could need a dedicated pool with
different parameters.
This is a suggested implementation where the pool is reused by default,
creating a dedicated one just if needed/asked. This way we ensure that
resources are under control and special cases are still handled.

2 files changed, 72 insertions, 4 deletions

diff --git a/src/leap/common/http.py b/src/leap/common/http.py
index 1dc5642..1e384e5 100644
--- a/src/leap/common/http.py
+++ b/src/leap/common/http.py
@@ -44,13 +44,21 @@ from twisted.web.http_headers import Headers
 from twisted.web.iweb import IBodyProducer
 
 
+def createPool(maxPersistentPerHost=10, persistent=True):
+    pool = HTTPConnectionPool(reactor, persistent)
+    pool.maxPersistentPerHost = maxPersistentPerHost
+    return pool
+
+_pool = createPool()
+
+
 class HTTPClient(object):
     """
     HTTP client done the twisted way, with a main focus on pinning the SSL
     certificate.
     """
 
-    def __init__(self, cert_file=None):
+    def __init__(self, cert_file=None, pool=_pool):
         """
         Init the HTTP client
 
@@ -58,15 +66,13 @@ class HTTPClient(object):
                           system's CAs will be used.
         :type cert_file: str
         """
-        self._pool = HTTPConnectionPool(reactor, persistent=True)
-        self._pool.maxPersistentPerHost = 10
 
         policy = get_compatible_ssl_context_factory(cert_file)
 
         self._agent = Agent(
             reactor,
             policy,
-            pool=self._pool)
+            pool=pool)
 
     def request(self, url, method='GET', body=None, headers={}):
         """
diff --git a/src/leap/common/tests/test_http.py b/src/leap/common/tests/test_http.py
new file mode 100644
index 0000000..e240ca3
--- /dev/null
+++ b/src/leap/common/tests/test_http.py
@@ -0,0 +1,62 @@
+# -*- coding: utf-8 -*-
+# test_http.py
+# Copyright (C) 2013 LEAP
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+Tests for:
+    * leap/common/http.py
+"""
+import os
+try:
+    import unittest2 as unittest
+except ImportError:
+    import unittest
+
+from leap.common import http
+from leap.common.testing.basetest import BaseLeapTest
+
+TEST_CERT_PEM = os.path.join(
+    os.path.split(__file__)[0],
+    '..', 'testing', "leaptest_combined_keycert.pem")
+
+
+class HTTPClientTest(BaseLeapTest):
+
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        pass
+
+    def test_agents_sharing_pool_by_default(self):
+        client = http.HTTPClient()
+        client2 = http.HTTPClient(TEST_CERT_PEM)
+        self.assertNotEquals(client._agent, client2._agent, "Expected dedicated agents")
+        self.assertEquals(client._agent._pool, client2._agent._pool, "Pool was not reused by default")
+
+    def test_agent_can_have_dedicated_custom_pool(self):
+        custom_pool = http.createPool(maxPersistentPerHost=42, persistent=False)
+        self.assertEquals(custom_pool.maxPersistentPerHost, 42,
+                          "Custom persistent connections limit is not being respected")
+        self.assertFalse(custom_pool.persistent,
+                         "Custom persistence is not being respected")
+        default_client = http.HTTPClient()
+        custom_client = http.HTTPClient(pool=custom_pool)
+
+        self.assertNotEquals(default_client._agent, custom_client._agent, "No agent reuse is expected")
+        self.assertEquals(custom_pool, custom_client._agent._pool, "Custom pool usage was not respected")
+
+if __name__ == "__main__":
+    unittest.main()