Add test storage driver

Create a "test" storage driver to be used by the
API test code.

blueprint api-server-pecan-wsme

Change-Id: I99c7c82afa17ec5a9f36fd20d47b16011e64ffa9
Signed-off-by: Doug Hellmann <doug.hellmann@dreamhost.com>

ceilometer/storage/impl_test.py

@@ -0,0 +1,85 @@
+# -*- encoding: utf-8 -*-
+#
+# Copyright © 2012 New Dream Network, LLC (DreamHost)
+#
+# Author: Doug Hellmann <doug.hellmann@dreamhost.com>
+#
+# 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.
+"""In-memory storage driver for use with tests.
+
+This driver is based on MIM, an in-memory version of MongoDB.
+"""
+
+import logging
+
+from ming import mim
+
+from ceilometer.storage import base
+from ceilometer.storage import impl_mongodb
+
+
+LOG = logging.getLogger(__name__)
+
+
+class TestDBStorage(base.StorageEngine):
+    """Put the data into an in-memory database for testing
+
+    This driver is based on MIM, an in-memory version of MongoDB.
+
+    Collections:
+
+    - user
+      - { _id: user id
+          source: [ array of source ids reporting for the user ]
+          }
+    - project
+      - { _id: project id
+          source: [ array of source ids reporting for the project ]
+          }
+    - meter
+      - the raw incoming data
+    - resource
+      - the metadata for resources
+      - { _id: uuid of resource,
+          metadata: metadata dictionaries
+          timestamp: datetime of last update
+          user_id: uuid
+          project_id: uuid
+          meter: [ array of {counter_name: string, counter_type: string} ]
+        }
+    """
+
+    OPTIONS = []
+
+    def register_opts(self, conf):
+        """Register any configuration options used by this engine.
+        """
+        conf.register_opts(self.OPTIONS)
+
+    def get_connection(self, conf):
+        """Return a Connection instance based on the configuration settings.
+        """
+        return TestConnection(conf)
+
+
+class TestConnection(impl_mongodb.Connection):
+
+    _mim_instance = None
+
+    def _get_connection(self, conf):
+        # MIM will die if we have too many connections, so use a
+        # Singleton
+        if TestConnection._mim_instance is None:
+            LOG.debug('Creating a new MIM Connection object')
+            TestConnection._mim_instance = mim.Connection()
+        return TestConnection._mim_instance

setup.py

@@ -127,5 +127,6 @@ setuptools.setup(
     mysql = ceilometer.storage.impl_sqlalchemy:SQLAlchemyStorage
     postgresql = ceilometer.storage.impl_sqlalchemy:SQLAlchemyStorage
     sqlite = ceilometer.storage.impl_sqlalchemy:SQLAlchemyStorage
+    test = ceilometer.storage.impl_test:TestDBStorage
     """),
     )