Log and collect stats for events consistently

Just happened to notice that the scheduler did a statsd call about
events with the gerrit name. That's not accurate anymore.

Pull that code into the connection so that we can use the driver name
and the connection name in the statsd calls and in the log message
emitted.

Change-Id: Ia5ed9458c0b28573392c576db7789b61f4d87f3b

tests/unit/test_scheduler.py

@@ -64,7 +64,11 @@ class TestScheduler(ZuulTestCase):
         self.assertIsNone(self.getJobFromHistory('project-test2').node)
 
         # TODOv3(jeblair): we may want to report stats by tenant (also?).
-        self.assertReportedStat('gerrit.event.comment-added', value='1|c')
+        # Per-driver
+        self.assertReportedStat('zuul.event.gerrit.comment-added', value='1|c')
+        # Per-driver per-connection
+        self.assertReportedStat('zuul.event.gerrit.gerrit.comment-added',
+                                value='1|c')
         self.assertReportedStat('zuul.pipeline.gate.current_changes',
                                 value='1|g')
         self.assertReportedStat('zuul.pipeline.gate.job.project-merge.SUCCESS',

zuul/connection/__init__.py

@@ -14,6 +14,7 @@
 
 import abc
 
+import extras
 import six
 
 
@@ -43,6 +44,26 @@ class BaseConnection(object):
         self.driver = driver
         self.connection_name = connection_name
         self.connection_config = connection_config
+        self.statsd = extras.try_import('statsd.statsd')
+
+    def logEvent(self, event):
+        self.log.debug(
+            'Scheduling {driver} event from {connection}: {event}'.format(
+                driver=self.driver.name,
+                connection=self.connection_name,
+                event=event.type))
+        try:
+            if self.statsd:
+                self.statsd.incr(
+                    'zuul.event.{driver}.{event}'.format(
+                        driver=self.driver.name, event=event.type))
+                self.statsd.incr(
+                    'zuul.event.{driver}.{connection}.{event}'.format(
+                        driver=self.driver.name,
+                        connection=self.connection_name,
+                        event=event.type))
+        except:
+            self.log.exception("Exception reporting event stats")
 
     def onLoad(self):
         pass

zuul/driver/gerrit/gerritconnection.py

@@ -143,6 +143,7 @@ class GerritEventConnector(threading.Thread):
             self.connection._getChange(event.change_number,
                                        event.patch_number,
                                        refresh=True)
+        self.connection.logEvent(event)
         self.connection.sched.addEvent(event)
 
     def run(self):

zuul/driver/github/githubconnection.py

@@ -72,7 +72,7 @@ class GithubWebhookListener():
 
         if event:
             event.project_hostname = self.connection.canonical_hostname
-            self.log.debug('Scheduling github event: {0}'.format(event.type))
+            self.connection.logEvent(event)
             self.connection.sched.addEvent(event)
 
     def _event_push(self, request):

zuul/scheduler.py

@@ -256,11 +256,6 @@ class Scheduler(threading.Thread):
 
     def addEvent(self, event):
         self.log.debug("Adding trigger event: %s" % event)
-        try:
-            if self.statsd:
-                self.statsd.incr('gerrit.event.%s' % event.type)
-        except:
-            self.log.exception("Exception reporting event stats")
         self.trigger_event_queue.put(event)
         self.wake_event.set()
         self.log.debug("Done adding trigger event: %s" % event)