Add user/project names to polled samples

Project and user names would be first fetched from cache, if not found,
they will be requested from keystone and then cached. Using cache will
significanlty reduce the number of calls made to keystone.

If ceilometer is configured with no caching backend, the results
will always be fetched by querying request to keystone.

A new config option, `tenant_name_discovery` is introduced
to operate this feature. This feature is optional and is disabled by default.

No attempts to identify names will be made if uuids are found to be `None`.

Signed-off-by: Yadnesh Kulkarni <ykulkarn@redhat.com>
Change-Id: Iee5dbf09a1fd3ac571746fc66d2683eb8e6a1b27

1 files changed, 62 insertions, 1 deletions

diff --git a/ceilometer/polling/manager.py b/ceilometer/polling/manager.py
index 6b9289d1..e5776a3e 100644
--- a/ceilometer/polling/manager.py
+++ b/ceilometer/polling/manager.py
@@ -35,6 +35,7 @@ from tooz import coordination
 from urllib import parse as urlparse
 
 from ceilometer import agent
+from ceilometer import cache_utils
 from ceilometer import declarative
 from ceilometer import keystone_client
 from ceilometer import messaging
@@ -45,6 +46,8 @@ from ceilometer import utils
 
 LOG = log.getLogger(__name__)
 
+CACHE_DURATION = 3600
+
 POLLING_OPTS = [
     cfg.StrOpt('cfg_file',
                default="polling.yaml",
@@ -64,7 +67,18 @@ POLLING_OPTS = [
     cfg.MultiStrOpt('pollsters_definitions_dirs',
                     default=["/etc/ceilometer/pollsters.d"],
                     help="List of directories with YAML files used "
-                         "to created pollsters.")
+                         "to created pollsters."),
+    cfg.BoolOpt('tenant_name_discovery',
+                default=False,
+                help="Identify project and user names from polled samples"
+                     "By default, collecting these values is disabled due"
+                     "to the fact that it could overwhelm keystone service"
+                     "with lots of continuous requests depending upon the"
+                     "number of projects, users and samples polled from"
+                     "the environment. While using this feature, it is"
+                     "recommended that ceilometer be configured with a"
+                     "caching backend to reduce the number of calls"
+                     "made to keystone"),
 ]
 
 
@@ -138,11 +152,39 @@ class PollingTask(object):
 
         self._telemetry_secret = self.manager.conf.publisher.telemetry_secret
 
+        self.ks_client = self.manager.keystone
+
+        self.cache_client = cache_utils.get_client(
+            self.manager.conf,
+            expiration_time=CACHE_DURATION
+        )
+
     def add(self, pollster, source):
         self.pollster_matches[source.name].add(pollster)
         key = Resources.key(source.name, pollster)
         self.resources[key].setup(source)
 
+    def resolve_uuid_from_cache(self, attr, uuid):
+        if self.cache_client:
+            name = self.cache_client.get(uuid)
+            if name:
+                return name
+            name = self.resolve_uuid_from_keystone(attr, uuid)
+            self.cache_client.set(uuid, name)
+            return name
+
+        # Retrieve project and user names from Keystone only
+        # if ceilometer doesn't have a caching backend
+        return self.resolve_uuid_from_keystone(attr, uuid)
+
+    def resolve_uuid_from_keystone(self, attr, uuid):
+        try:
+            return getattr(self.ks_client, attr).get(uuid).name
+        except AttributeError as e:
+            LOG.warning("Found '%s' while resolving uuid %s to name", e, uuid)
+        except ka_exceptions.NotFound as e:
+            LOG.warning(e.message)
+
     def poll_and_notify(self):
         """Polling sample and notify."""
         cache = {}
@@ -194,6 +236,25 @@ class PollingTask(object):
                     for sample in samples:
                         # Note(yuywz): Unify the timestamp of polled samples
                         sample.set_timestamp(polling_timestamp)
+
+                        if self.manager.conf.tenant_name_discovery:
+
+                            # Try to resolve project UUIDs from cache first,
+                            # and then keystone
+                            if sample.project_id:
+                                sample.project_name = \
+                                    self.resolve_uuid_from_cache(
+                                        "projects", sample.project_id
+                                    )
+
+                            # Try to resolve user UUIDs from cache first,
+                            # and then keystone
+                            if sample.user_id:
+                                sample.user_name = \
+                                    self.resolve_uuid_from_cache(
+                                        "users", sample.user_id
+                                    )
+
                         sample_dict = (
                             publisher_utils.meter_message_from_counter(
                                 sample, self._telemetry_secret