Merge "Copy Gerrit delay to GitHub driver" into feature/zuulv3

zuul/driver/github/githubconnection.py

@@ -135,6 +135,7 @@ class GithubEventConnector(threading.Thread):
     """Move events from GitHub into the scheduler"""
 
     log = logging.getLogger("zuul.GithubEventConnector")
+    delay = 3.0
 
     def __init__(self, connection):
         super(GithubEventConnector, self).__init__()
@@ -147,9 +148,17 @@ class GithubEventConnector(threading.Thread):
         self.connection.addEvent(None)
 
     def _handleEvent(self):
-        json_body, event_type = self.connection.getEvent()
+        ts, json_body, event_type = self.connection.getEvent()
         if self._stopped:
             return
+        # Github can produce inconsistent data immediately after an
+        # event, So ensure that we do not deliver the event to Zuul
+        # until at least a certain amount of time has passed.  Note
+        # that if we receive several events in succession, we will
+        # only need to delay for the first event.  In essence, Zuul
+        # should always be a constant number of seconds behind Github.
+        now = time.time()
+        time.sleep(max((ts + self.delay) - now, 0.0))
 
         # If there's any installation mapping information in the body then
         # update the project mapping before any requests are made.
@@ -543,7 +552,7 @@ class GithubConnection(BaseConnection):
         return token
 
     def addEvent(self, data, event=None):
-        return self.event_queue.put((data, event))
+        return self.event_queue.put((time.time(), data, event))
 
     def getEvent(self):
         return self.event_queue.get()