datajam: capture answers to problems

example/src/datajam/datajam/settings.py

@@ -33,6 +33,7 @@ TIME_BETWEEN_DATA_REGENERATION = datetime.timedelta(minutes=1)
 INSTALLED_ANALYTICS_MODULES = [
     'modules.dump_to_db',
     'modules.instructor_dash',
+    'modules.problem_answers',
 ]
 
 print INSTALLED_ANALYTICS_MODULES

example/src/datajam/modules/problem_answers.py

+from bson.json_util import dumps
+
+from edinsights.core.decorators import event_handler
+from edinsights.core.decorators import query
+
+
+@query()
+def all_problem_answers(mongodb):
+    """
+    Returns a list of records each containing the problem, the student response
+    and the number of times that response has been seen for that problem.
+
+    Example::
+    
+        [
+          { 
+            "question": "i4x-edX-E101-problem-a0effb954cca4759994f1ac9e9434bf4_3_1",
+            "answer": "choice_0",
+            "count": 5
+          },
+          { 
+            "question": "i4x-edX-E101-problem-a0effb954cca4759994f1ac9e9434bf4_3_1",
+            "answer": "blue",
+            "count": 30
+          },
+        ]
+    """
+    return dumps(mongodb['problem_answers'].find())
+
+
+@event_handler()
+def handle_problem_checks(mongodb, events):
+    collection = mongodb['problem_answers']
+    answers = []
+    for event_wrapper in events:
+        event = event_wrapper.event
+        has_event_field = 'event' in event
+        is_problem_check = event.get('event_type') == 'problem_check'
+        is_from_server = event.get('event_source') == 'server'
+        if is_problem_check and is_from_server and has_event_field:
+            for question, answer in event.get('event', {}).get('answers', {}).iteritems():
+                collection.update(
+                    {
+                        'question': question,
+                        'answer': answer
+                    },
+                    { '$inc': {'count': 1} },
+                    upsert=True
+                )