add a filter to get_courses to not surface any courses that haven't been mapped, unless the store provider has been labeled as 'default'

common/lib/xmodule/xmodule/modulestore/mixed.py

@@ -103,7 +103,20 @@ class MixedModuleStore(ModuleStoreBase):
         '''
         courses = []
         for key in self.modulestores:
-            courses = courses + (self.modulestores[key].get_courses())
+            store_courses = self.modulestores[key].get_courses()
+            # If the store has not been labeled as 'default' then we should
+            # only surface courses that have a mapping entry, for example the XMLModuleStore will
+            # slurp up anything that is on disk, however, we don't want to surface those to
+            # consumers *unless* there is an explicit mapping in the configuration
+            if key != 'default':
+                for course in store_courses:
+                    # make sure that the courseId is mapped to the store in question
+                    if key == self.mappings.get(course.location.course_id, 'default'):
+                        courses = courses + ([course])
+            else:
+                # if we're the 'default' store provider, then we surface all courses hosted in
+                # that store provider
+                courses = courses + (store_courses)
 
         return courses
 

common/lib/xmodule/xmodule/modulestore/tests/test_mixed_modulestore.py

@@ -187,6 +187,7 @@ class TestMixedModuleStore(object):
     def test_get_courses(self):
         # we should have 3 total courses aggregated
         courses = self.store.get_courses()
+        assert_equals(len(courses), 3)
         course_ids = []
         for course in courses:
             course_ids.append(course.location.course_id)