[Classroom Status] Add class to serialize User Actions

courses/stats/serializers.py

 from rest_framework import serializers
+from actstream.models import Action
+from courses.reports.serializers import UserStatsSerializer
+
+from django.contrib.auth.models import User
+from django.contrib.auth import get_user_model
+User = get_user_model()
+
+from courses.classroom.models import Classroom
+from courses.classroom.serializers import BasicClassroomSerializer
 
 
 class UserActionsSerializer(serializers.Serializer):
@@ -11,3 +20,23 @@ class UserActionsSerializer(serializers.Serializer):
 
 class UserAccessSerializer(serializers.Serializer):
     area = serializers.CharField(required=True, max_length=100)
+
+
+class GenericRelatedField(serializers.Field):
+    def to_representation(self, value):
+        if isinstance(value, User):
+            return UserStatsSerializer(value).data
+        if isinstance(value, Classroom):
+            return BasicClassroomSerializer(value).data
+        return str(value)
+
+
+class ActionSerializer(serializers.ModelSerializer):
+    actor = GenericRelatedField(read_only=True)
+    target = GenericRelatedField(read_only=True)
+    action_object = GenericRelatedField(read_only=True)
+    verb = GenericRelatedField(read_only=True)
+
+    class Meta:
+        model = Action
+        fields = ('actor', 'target', 'action_object', 'verb')

courses/stats/views.py

 from actstream import action
+from actstream.models import user_stream, Action, actor_stream
+
 from rest_framework import views, viewsets, mixins, permissions, status
 from rest_framework.response import Response
 from rest_framework.permissions import IsAuthenticated
+from rest_framework.pagination import PageNumberPagination
 
 from discussion.models import Forum, Topic
-from .serializers import UserActionsSerializer, UserAccessSerializer
+from .serializers import UserActionsSerializer, UserAccessSerializer, ActionSerializer
 from .models import AccessibleArea
 from ..models import Course
 from ..classroom.models import Classroom
 
+from django.contrib.auth.models import User
+from django.contrib.auth import get_user_model
+
+User = get_user_model()
+
 
 class UserActionsView(views.APIView):
     permission_classes = [permissions.IsAuthenticated]
@@ -63,3 +71,24 @@ class UserAccessView(views.APIView):
         action.send(request.user, verb='access', action_object=action_object)
 
         return Response(None, status=status.HTTP_201_CREATED)
+
+
+class ActivitiesPagination(PageNumberPagination):
+    page_size = 50
+    page_size_query_param = 'page_size'
+    max_page_size = 100
+
+
+class UserActivitiesViewSet(viewsets.ReadOnlyModelViewSet):
+    serializer_class = ActionSerializer
+    permission_classes = [permissions.IsAuthenticated]
+    pagination_class = ActivitiesPagination
+    model = Action
+
+    def get_queryset(self):
+        user_id = self.request.GET.get('user')
+        user = User.objects.get(id=user_id)
+
+        queryset = actor_stream(user)
+
+        return queryset