Add caching support to catalog

We will now cache the results of the catalog for 60s and not hit the database at all if cached

test/registry/protocol_v2.py

@@ -390,7 +390,7 @@ class V2Protocol(RegistryProtocol):
     return results
 
   def catalog(self, session, page_size=2, credentials=None, options=None, expected_failure=None,
-              namespace=None, repo_name=None):
+              namespace=None, repo_name=None, bearer_token=None):
     options = options or ProtocolOptions()
     scopes = options.scopes or []
 
@@ -409,6 +409,11 @@ class V2Protocol(RegistryProtocol):
         'Authorization': 'Bearer ' + token,
       }
 
+    if bearer_token is not None:
+      headers = {
+        'Authorization': 'Bearer ' + bearer_token,
+      }
+
     results = []
     url = '/v2/_catalog'
     params = {}

test/registry/registry_tests.py

@@ -719,6 +719,26 @@ def test_catalog(public_catalog, credentials, expected_repos, page_size, v2_prot
     assert set(expected_repos).issubset(set(results))
 
 
+def test_catalog_caching(v2_protocol, basic_images, liveserver_session, app_reloader,
+                         liveserver, registry_server_executor):
+  """ Test: Calling the catalog after initially pulled will result in the catalog being cached. """
+  credentials = ('devtable', 'password')
+
+  # Conduct the initial catalog call to prime the cache.
+  results = v2_protocol.catalog(liveserver_session, credentials=credentials,
+                                namespace='devtable', repo_name='simple')
+
+  token, _ = v2_protocol.auth(liveserver_session, credentials, 'devtable', 'simple')
+
+  # Disconnect the server from the database.
+  registry_server_executor.on(liveserver).break_database()
+
+  # Call the catalog again, which should now be cached.
+  cached_results = v2_protocol.catalog(liveserver_session, bearer_token=token)
+  assert len(cached_results) == len(results)
+  assert set(cached_results) == set(results)
+
+
 @pytest.mark.parametrize('username, namespace, repository', [
   ('devtable', 'devtable', 'simple'),
   ('devtable', 'devtable', 'gargantuan'),