Add notifier plugin based on Ceilometer

This drivers sends notifications using notifer API from oslo.messaging

These notifications has speical topic "profiler", and they are collected
by this Ceilometer notification pluging:

https://review.openstack.org/#/c/100239/

Change-Id: I305fc7a13d3c052ffd22073d77ae4f12fae348ca

osprofiler/__init__.py

@@ -0,0 +1,20 @@
+# Copyright 2011 OpenStack Foundation.
+# All Rights Reserved.
+#
+#    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.
+
+
+from osprofiler import _utils as utils
+
+
+utils.import_modules_from_package("osprofiler._notifiers")

osprofiler/_notifiers/base.py

@@ -18,11 +18,26 @@ from osprofiler import _utils as utils
 
 class Notifier(object):
 
-    def notify(self, info):
+    def notify(self, info, context=None):
         """This method will be called on each notifier.notify() call.
 
         To add new drivers you should, create new subclass of this class and
         implement notify method.
+
+        :param info:  Contains information about trace element.
+                      In payload dict there are always 3 ids:
+                      "base_id" - uuid that is common for all notifications
+                                  related to one trace. Used to simplify
+                                  retrieving of all trace elements from
+                                  Ceilometer.
+                      "parent_id" - uuid of parent element in trace
+                      "trace_id" - uuid of current element in trace
+
+                      With parent_id and trace_id it's quite simple to build
+                      tree of trace elements, which simplify analyze of trace.
+
+        :param context: request context that is mostly used to specify
+                        current active user and tenant.
         """
 
     @staticmethod

osprofiler/_notifiers/messaging.py

@@ -12,3 +12,45 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+
+from osprofiler._notifiers import base
+
+
+class Messaging(base.Notifier):
+
+    def __init__(self, messaging, context, transport, project, service, host):
+        """Init Messaging notify driver.
+
+        """
+        super(Messaging, self).__init__()
+        self.messaging = messaging
+        self.context = context
+        self.project = project
+        self.service = service
+
+        self.notifier = messaging.Notifier(
+            transport, publisher_id=host, driver="messaging", topic="profiler")
+
+    def notify(self, info, context=None):
+        """Send notifications to Ceilometer via oslo.messaging notifier API.
+
+        :param info:  Contains information about trace element.
+                      In payload dict there are always 3 ids:
+                      "base_id" - uuid that is common for all notifications
+                                  related to one trace. Used to simplify
+                                  retrieving of all trace elements from
+                                  Ceilometer.
+                      "parent_id" - uuid of parent element in trace
+                      "trace_id" - uuid of current element in trace
+
+                      With parent_id and trace_id it's quite simple to build
+                      tree of trace elements, which simplify analyze of trace.
+
+        :param context: request context that is mostly used to specify
+                        current active user and tenant.
+        """
+
+        info["project"] = self.project
+        info["service"] = self.service
+        self.notifier.info(context or self.context,
+                           "profiler.%s" % self.service, info)

osprofiler/_utils.py

@@ -17,6 +17,8 @@ import base64
 import hashlib
 import hmac
 import json
+import os
+
 import six
 
 
@@ -110,3 +112,19 @@ def itersubclasses(cls, _seen=None):
             yield sub
             for sub in itersubclasses(sub, _seen):
                 yield sub
+
+
+def import_modules_from_package(package):
+    """Import modules from package and append into sys.modules
+
+    :param: package - Full package name. For example: rally.deploy.engines
+    """
+    path = [os.path.dirname(__file__), '..'] + package.split('.')
+    path = os.path.join(*path)
+    for root, dirs, files in os.walk(path):
+        for filename in files:
+            if filename.startswith('__') or not filename.endswith('.py'):
+                continue
+            new_package = ".".join(root.split(os.sep)).split("....")[1]
+            module_name = '%s.%s' % (new_package, filename[:-3])
+            __import__(module_name)

osprofiler/notifier.py

@@ -16,7 +16,7 @@
 from osprofiler._notifiers import base
 
 
-def _noop_notifier(info):
+def _noop_notifier(info, context=None):
     """Do nothing on notify()."""
     pass
 

tests/notifiers/test_base.py

@@ -13,6 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import mock
+
 from osprofiler._notifiers import base
 from tests import test
 
@@ -46,3 +48,7 @@ class NotifierBaseTestCase(test.TestCase):
 
     def test_notify(self):
         base.Notifier().notify("")
+
+    def test_plugins_are_imported(self):
+        base.Notifier.factory("Messaging", mock.MagicMock(), "context",
+                              "transport", "project", "service", "host")