Add leading period so we don't get partial matches on extensions.

common/djangoapps/static_replace/models.py

@@ -44,7 +44,8 @@ class AssetExcludedExtensionsConfig(ConfigurationModel):
     @classmethod
     def get_excluded_extensions(cls):
         """Gets the excluded file extensions when canonicalizing static asset paths"""
-        return cls.current().excluded_extensions.split()
+        add_period = lambda x: '.' + x
+        return map(add_period, cls.current().excluded_extensions.split())
 
     def __repr__(self):
         return '<AssetExcludedExtensionsConfig(extensions={})>'.format(self.get_excluded_extensions().split())

common/djangoapps/static_replace/test/test_static_replace.py

@@ -445,6 +445,7 @@ class CanonicalContentTest(SharedModuleStoreTestCase):
     )
     @ddt.unpack
     def test_canonical_asset_path_with_new_style_assets(self, base_url, start, expected, mongo_calls):
+        exts = ['.html', '.tm']
         prefix = 'split'
         encoded_base_url = quote_plus('//' + base_url)
         c4x = 'c4x/a/b/asset'
@@ -473,7 +474,7 @@ class CanonicalContentTest(SharedModuleStoreTestCase):
         )
 
         with check_mongo_calls(mongo_calls):
-            asset_path = StaticContent.get_canonicalized_asset_path(self.courses[prefix].id, start, base_url, ['html'])
+            asset_path = StaticContent.get_canonicalized_asset_path(self.courses[prefix].id, start, base_url, exts)
             self.assertEqual(asset_path, expected)
 
     @ddt.data(
@@ -630,6 +631,7 @@ class CanonicalContentTest(SharedModuleStoreTestCase):
     )
     @ddt.unpack
     def test_canonical_asset_path_with_c4x_style_assets(self, base_url, start, expected, mongo_calls):
+        exts = ['.html', '.tm']
         prefix = 'old'
         c4x_block = 'c4x/a/b/asset'
         encoded_c4x_block = quote_plus('/' + c4x_block + '/')
@@ -649,5 +651,5 @@ class CanonicalContentTest(SharedModuleStoreTestCase):
         )
 
         with check_mongo_calls(mongo_calls):
-            asset_path = StaticContent.get_canonicalized_asset_path(self.courses[prefix].id, start, base_url, ['html'])
+            asset_path = StaticContent.get_canonicalized_asset_path(self.courses[prefix].id, start, base_url, exts)
             self.assertEqual(asset_path, expected)

common/lib/xmodule/xmodule/contentstore/content.py

@@ -201,10 +201,8 @@ class StaticContent(object):
 
         # See if this is an allowed file extension to serve.  Some files aren't served through the
         # CDN in order to avoid same-origin policy/CORS-related issues.
-        for excluded_ext in excluded_exts:
-            if relative_path.lower().endswith(excluded_ext.lower()):
+        if any(relative_path.lower().endswith(excluded_ext.lower()) for excluded_ext in excluded_exts):
             serve_from_cdn = False
-                break
 
         # Update any query parameter values that have asset paths in them. This is for assets that
         # require their own after-the-fact values, like a Flash file that needs the path of a config