add acceptance tests for event tracking

lms/djangoapps/courseware/features/events.feature

+@shard_2
+Feature: LMS.Events
+  As a researcher, I want to be able to track events in the LMS
+
+  Scenario Outline: An event is emitted for each request
+    Given: I am registered for the course "6.002x"
+    And I visit the url "<url>"
+    Then a "<url>" server event is emitted
+
+  Examples:
+    | url                                        |
+    | /dashboard                                 |
+    | /courses/edx/6.002x/Test_Course/info       |
+    | /courses/edx/6.002x/Test_Course/courseware |

lms/djangoapps/courseware/features/events.py

+#pylint: disable=C0111
+
+from lettuce import step
+from lettuce import world
+from lettuce import before
+from pymongo import MongoClient
+from nose.tools import assert_equals
+from nose.tools import assert_in
+
+
+@before.all
+def connect_to_mongodb():
+    world.mongo_client = MongoClient()
+    world.event_collection = world.mongo_client['track']['events']
+
+
+@before.each_scenario
+def reset_captured_events(_scenario):
+    world.event_collection.drop()
+
+
+@before.outline
+def reset_between_outline_scenarios(_scenario, order, outline, reasons_to_fail):
+    world.event_collection.drop()
+
+
+@step('[aA]n? "(.*)" (server|browser) event is emitted')
+def event_is_emitted(_step, event_type, event_source):
+
+    # Ensure all events are written out to mongo before querying.
+    world.mongo_client.fsync()
+
+    # Note that splinter makes 2 requests when you call browser.visit('/foo')
+    # the first just checks to see if the server responds with a status
+    # code of 200, the next actually uses the browser to submit the request.
+    # We filter out events associated with the status code checks by ignoring
+    # events that come directly from splinter.
+    criteria = {
+        'event_type': event_type,
+        'event_source': event_source,
+        'agent': {
+            '$ne': 'python/splinter'
+        }
+    }
+    cursor = world.event_collection.find(criteria)
+    assert_equals(cursor.count(), 1)
+
+    event = cursor.next()
+
+    # These fields should be present in the event, but we won't bother
+    # validating them since it is difficult to predict their values.
+    for expected_field in ['host', 'time', 'agent', 'ip', 'event_source', 'event', 'page']:
+        assert_in(expected_field, event, msg='Expected field {} not found in event'.format(expected_field))
+
+    expected_field_values = {
+        "username": world.scenario_dict['USER'].username,
+        "event_type": event_type,
+    }
+    for key, value in expected_field_values.iteritems():
+        assert_equals(event[key], value)
+
+    # Note that the event may contain other fields, which is fine!

lms/djangoapps/courseware/features/navigation.feature

@@ -18,6 +18,7 @@ Feature: LMS.Navigate Course
         Given I am viewing a section with multiple sequences
         When I navigate to an item in a sequence
         Then I see the content of the sequence item
+        And a "seq_goto" browser event is emitted
 
     Scenario: I can return to the last section I visited
         Given I am viewing a course with multiple sections

lms/djangoapps/courseware/features/problems.feature

@@ -10,6 +10,8 @@ Feature: LMS.Answer problems
         When I answer a "<ProblemType>" problem "correctly"
         Then my "<ProblemType>" answer is marked "correct"
         And The "<ProblemType>" problem displays a "correct" answer
+        And a "problem_check" server event is emitted
+        And a "problem_check" browser event is emitted
 
         Examples:
         | ProblemType       |

lms/envs/acceptance.py

@@ -74,6 +74,12 @@ DATABASES = {
     }
 }
 
+TRACKING_BACKENDS.update({
+    'mongo': {
+        'ENGINE': 'track.backends.mongodb.MongoBackend'
+    }
+})
+
 # Forums are disabled in test.py to speed up unit tests, but we do not have
 # per-test control for acceptance tests
 MITX_FEATURES['ENABLE_DISCUSSION_SERVICE'] = True