Added gunicorn as server application manager

This patch adds gunicorn as dependency for starting and managing server
workers. Gunicorn allow users to chose whether to use workers based on a
sync process, eventlet or gevent. It also manages multiple workers, ssl,
process uid, process gid.

Implements blueprint transport-base

Change-Id: Ic328dbb937f8df69691911c6e6ff6b318bb1db34

etc/marconi.conf-sample

@@ -5,7 +5,17 @@ transport = marconi.transport.wsgi
 storage = marconi.storage.mongodb
 
 [drivers:transport:wsgi]
-port = 8888
+bind = 0.0.0.0:8888
+; workers = 4
+workers = 1
+; worker_class = sync, gevent, eventlet
+worker_class = sync
+; user = 1000
+; group = 1000
+; proc_name = marconi
+; certfile = cert.crt
+; keyfile = cert.key
+
 
 ;[drivers:transport:zmq]
 ;port = 9999

marconi/tests/etc/wsgi_sqlite.conf

@@ -3,4 +3,5 @@ transport = marconi.transport.wsgi
 storage = marconi.storage.sqlite
 
 [drivers:transport:wsgi]
-port = 8888
+bind = 0.0.0.0:8888
+workers = 20

marconi/tests/transport/wsgi/test_app.py

@@ -0,0 +1,40 @@
+# Copyright (c) 2013 Red Hat, Inc.
+#
+# 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.
+
+import multiprocessing
+import signal
+
+import marconi
+from marconi.tests import util
+from marconi.transport.wsgi import app
+
+
+class TestApplication(util.TestBase):
+
+    def setUp(self):
+        super(TestApplication, self).setUp()
+
+        conf_file = self.conf_path('wsgi_sqlite.conf')
+        boot = marconi.Bootstrap(conf_file)
+
+        self.app = app.Application(boot.transport.app)
+
+    def test_run(self):
+        server = multiprocessing.Process(target=self.app.run)
+        server.start()
+        self.assertTrue(server.is_alive())
+        server.terminate()
+        server.join()
+        self.assertEquals(server.exitcode, -signal.SIGTERM)

marconi/transport/wsgi/app.py

@@ -0,0 +1,57 @@
+# Copyright (c) 2013 Red Hat, Inc.
+#
+# 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.
+"""
+Gunicorn Application implementation for Marconi
+"""
+
+import gunicorn.app.base as gunicorn
+import gunicorn.config as gconfig
+
+from marconi.common import config
+
+
+OPTIONS = {
+    # Process
+    "user": None,
+    "group": None,
+    "proc_name": "marconi",
+
+    # SSL
+    "certfile": None,
+    "keyfile": None,
+
+    # Network
+    "workers": 1,
+    "bind": "0.0.0.0:8888",
+    "worker_class": "sync"
+}
+
+cfg = config.namespace('drivers:transport:wsgi').from_options(**OPTIONS)
+
+
+class Application(gunicorn.Application):
+
+    def __init__(self, wsgi_app, *args, **kwargs):
+        super(Application, self).__init__(*args, **kwargs)
+        self.app = wsgi_app
+
+    def load(self):
+        return self.app
+
+    def load_config(self):
+        self.cfg = gconfig.Config(self.usage, prog=self.prog)
+
+        for key in OPTIONS:
+            self.cfg.set(key, getattr(cfg, key))

marconi/transport/wsgi/driver.py

@@ -15,11 +15,8 @@
 
 import falcon
 
-from marconi.common import config
 from marconi import transport
-
+from marconi.transport.wsgi import app
-
-cfg = config.namespace('drivers:transport:wsgi').from_options(port=8888)
 
 
 class Driver(transport.DriverBase):
@@ -56,4 +53,4 @@ class Driver(transport.DriverBase):
                       '/claims/{claim_id}', claim_item)
 
     def listen(self):
-        raise NotImplementedError
+        return app.Application(self.app).run()

tools/pip-requires

@@ -6,4 +6,5 @@ PasteDeploy
 pymongo
 python-keystoneclient
 WebOb
+gunicorn
 iso8601>=0.1.4