Add option to disable SSL compression

Allows optionally disabling SSL compression. This can significantly
improve HTTPS upload/download performance in some cases -- in particular
when the object is not compressible and you have very high network
bandwidth.

Implements blueprint ssl-compression.

Change-Id: I1260055f9c2e83cdabfeb51aed11b3899bed4d55

1 files changed, 95 insertions, 0 deletions

diff --git a/swiftclient/https_connection.py b/swiftclient/https_connection.py
new file mode 100644
index 0000000..2a2dc1f
--- /dev/null
+++ b/swiftclient/https_connection.py
@@ -0,0 +1,95 @@
+# Copyright (c) 2013 OpenStack, LLC.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+HTTPS/SSL related functionality
+"""
+
+import socket
+
+from httplib import HTTPSConnection
+
+import OpenSSL
+
+try:
+    from eventlet.green.OpenSSL.SSL import GreenConnection
+    from eventlet.greenio import GreenSocket
+    from eventlet.patcher import is_monkey_patched
+
+    def getsockopt(self, *args, **kwargs):
+        return self.fd.getsockopt(*args, **kwargs)
+    # The above is a workaround for an eventlet bug in getsockopt.
+    # TODO(mclaren): Workaround can be removed when this fix lands:
+    # https://bitbucket.org/eventlet/eventlet/commits/609f230
+    GreenSocket.getsockopt = getsockopt
+except ImportError:
+    def is_monkey_patched(*args):
+        return False
+
+
+class HTTPSConnectionNoSSLComp(HTTPSConnection):
+    """
+    Extended HTTPSConnection which uses the OpenSSL library
+    for disabling SSL compression.
+    Note: This functionality can eventually be replaced
+          with native Python 3.3 code.
+    """
+    def __init__(self, host):
+        HTTPSConnection.__init__(self, host)
+        self.setcontext()
+
+    def setcontext(self):
+        """
+        Set up the OpenSSL context.
+        """
+        self.context = OpenSSL.SSL.Context(OpenSSL.SSL.SSLv23_METHOD)
+        # Disable SSL layer compression.
+        self.context.set_options(0x20000)  # SSL_OP_NO_COMPRESSION
+
+    def connect(self):
+        """
+        Connect to an SSL port using the OpenSSL library and apply
+        per-connection parameters.
+        """
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.sock = OpenSSLConnectionDelegator(self.context, sock)
+        self.sock.connect((self.host, self.port))
+
+
+class OpenSSLConnectionDelegator(object):
+    """
+    An OpenSSL.SSL.Connection delegator.
+
+    Supplies an additional 'makefile' method which httplib requires
+    and is not present in OpenSSL.SSL.Connection.
+
+    Note: Since it is not possible to inherit from OpenSSL.SSL.Connection
+    a delegator must be used.
+    """
+    def __init__(self, *args, **kwargs):
+        if is_monkey_patched('socket'):
+            # If we are running in a monkey patched environment
+            # use eventlet's GreenConnection -- it handles eventlet's
+            # non-blocking sockets correctly.
+            Connection = GreenConnection
+        else:
+            Connection = OpenSSL.SSL.Connection
+        self.connection = Connection(*args, **kwargs)
+
+    def __getattr__(self, name):
+        return getattr(self.connection, name)
+
+    def makefile(self, *args, **kwargs):
+        return socket._fileobject(self.connection, *args, **kwargs)