fix: Forwarding Event Processor defaults to default event dispatcher (#235)

* tests: fail unit test

* fix: default ForwardingEventProcessor to use default event dispatcher

Author: oakbani

optimizely/event/event_processor.py

@@ -1,4 +1,4 @@
-# Copyright 2019 Optimizely
+# Copyright 2019-2020 Optimizely
 # 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
@@ -335,7 +335,7 @@ def __init__(self, event_dispatcher, logger=None, notification_center=None):
       logger: Optional component which provides a log method to log messages. By default nothing would be logged.
       notification_center: Optional instance of notification_center.NotificationCenter.
     """
-        self.event_dispatcher = event_dispatcher
+        self.event_dispatcher = event_dispatcher or default_event_dispatcher
         self.logger = _logging.adapt_logger(logger or _logging.NoOpLogger())
         self.notification_center = notification_center or _notification_center.NotificationCenter(self.logger)
 

tests/test_event_processor.py

@@ -1,4 +1,4 @@
-# Copyright 2019, Optimizely
+# Copyright 2019-2020, Optimizely
 # 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
@@ -24,6 +24,7 @@
 from optimizely.event.event_factory import EventFactory
 from optimizely.event.log_event import LogEvent
 from optimizely.event.user_event_factory import UserEventFactory
+from optimizely.event_dispatcher import EventDispatcher as default_event_dispatcher
 from optimizely.helpers import enums
 from optimizely.logger import SimpleLogger
 from . import base
@@ -561,3 +562,10 @@ def on_log_event(log_event):
         self.assertEqual(
             1, len(self.optimizely.notification_center.notification_listeners[enums.NotificationTypes.LOG_EVENT]),
         )
+
+    def test_event_processor_defaults_to_default_event_dispatcher(self):
+        event_processor = ForwardingEventProcessor(None)
+        self.assertEqual(
+            event_processor.event_dispatcher,
+            default_event_dispatcher
+        )