Make memcache/taskqueue stubs throw better error messages.

pcostell · pcostell · commit 698d0284c490 · 2015-12-01T10:41:25.000-08:00
diff --git a/ndb/tasklets.py b/ndb/tasklets.py
@@ -1192,6 +1192,18 @@ def _make_cloud_datastore_context(app_id, external_app_ids=()):
   except:
     pass  # The stub is already installed.
   # TODO(pcostello): Ensure the current stub is connected to the right project.
+
+  # Install a memcache and taskqueue stub which throws on everything.
+  try:
+    apiproxy_stub_map.apiproxy.RegisterStub('memcache', _ThrowingStub())
+  except:
+    pass  # The stub is already installed.
+  try:
+    apiproxy_stub_map.apiproxy.RegisterStub('taskqueue', _ThrowingStub())
+  except:
+    pass  # The stub is already installed.
+
+
   return make_context(conn=conn)
 
 
@@ -1200,6 +1212,17 @@ def set_context(new_context):
   os.environ[_CONTEXT_KEY] = '1'
   _state.current_context = new_context
 
+class _ThrowingStub(object):
+  """A Stub implementation which always throws a NotImplementedError."""
+
+  # pylint: disable=invalid-name
+  def MakeSyncCall(self, service, call, request, response):
+    raise NotImplementedError('In order to use %s.%s you must '
+                              'install the Remote API.' % (service, call))
+
+  # pylint: disable=invalid-name
+  def CreateRPC(self):
+    return apiproxy_rpc.RPC(stub=self)
 
 # TODO: Rework the following into documentation.
 
diff --git a/ndb/tasklets_test.py b/ndb/tasklets_test.py
@@ -26,6 +26,7 @@
 from .google_imports import datastore_pbs
 from .google_imports import datastore_rpc
 from .google_imports import namespace_manager
+from .google_imports import taskqueue
 from .google_test_imports import unittest
 from .google_test_imports import real_unittest
 
@@ -785,48 +786,6 @@ class Employee(model.Model):
     self.assertEqual(fn(m), True)
     self.assertEqual(key.Key(Employee, 'mykey').get().name, 'Patrick')
 
-  @real_unittest.skipUnless(
-      datastore_pbs._CLOUD_DATASTORE_ENABLED,
-      "V1 must be supported to run V1 tests.")
-  def testCloudDatastoreContext(self):
-    del os.environ['APPLICATION_ID']  # Clear APPLICATION_ID for test.
-    os.environ['DATASTORE_PROJECT_ID'] = 'project'
-    # Setting just a project id isn't enough info.
-    self.assertRaisesRegexp(ValueError,
-                            'Could not determine app id\..*',
-                            tasklets.make_default_context)
-    # Unless the override is specified.
-    os.environ['DATASTORE_USE_PROJECT_ID_AS_APP_ID'] = 'True'
-    ctx = tasklets.make_default_context()
-    self.assertEqual(datastore_rpc._CLOUD_DATASTORE_V1, ctx._conn._api_version)
-    os.environ['DATASTORE_APP_ID'] = 's~project'
-    # App id and override should not both be specified
-    self.assertRaisesRegexp(ValueError,
-                            'App id was provided .* but .* was set to true\.',
-                            tasklets.make_default_context)
-    del os.environ['DATASTORE_USE_PROJECT_ID_AS_APP_ID']
-    ctx = tasklets.make_default_context()
-    self.assertEqual(datastore_rpc._CLOUD_DATASTORE_V1, ctx._conn._api_version)
-    os.environ['DATASTORE_APP_ID'] = 's~anotherproject'
-    # The provided app id must resolve to the provided project id.
-    self.assertRaises(ValueError, tasklets.make_default_context)
-    os.environ['DATASTORE_APP_ID'] = 's~project'
-    os.environ['DATASTORE_ADDITIONAL_APP_IDS'] = 's~anotherapp,s~andanother'
-    ctx = tasklets.make_default_context()
-    converter = ctx._conn.adapter.get_entity_converter()
-    self.assertEquals('s~anotherapp', converter.project_to_app_id('anotherapp'))
-    self.assertEquals('s~andanother', converter.project_to_app_id('andanother'))
-
-  @real_unittest.skipUnless(
-      datastore_pbs._CLOUD_DATASTORE_ENABLED,
-      "V1 must be supported to run V1 tests.")
-  def testCloudDatastoreContextWithExistingApplicationId(self):
-    os.environ['DATASTORE_APP_ID'] = 's~project'
-    os.environ['DATASTORE_PROJECT_ID'] = 'project'
-    os.environ['APPLICATION_ID'] = 's~a-different-project'
-    # If things are set propertly but APPLICATION_ID is already set, we fail.
-    self.assertRaises(ValueError, tasklets.make_default_context)
-
 
 class TracebackTests(test_utils.NDBTest):
   """Checks that errors result in reasonable tracebacks."""
@@ -888,5 +847,63 @@ def testYieldError(self):
           str(err)))
 
 
+@real_unittest.skipUnless(datastore_pbs._CLOUD_DATASTORE_ENABLED,
+                          "V1 must be supported to run V1 tests.")
+class CloudDatastoreContextCreationTests(test_utils.NDBCloudDatastoreV1Test):
+  """Context tests that use a Cloud Datastore V1 connection."""
+
+  def setUp(self):
+    super(CloudDatastoreContextCreationTests, self).setUp()
+    self.HRTest()
+    self.ctx = tasklets._make_cloud_datastore_context(self.APP_ID)
+    tasklets.set_context(self.ctx)
+
+  def testCloudDatastoreContext(self):
+    del os.environ['APPLICATION_ID']  # Clear APPLICATION_ID for test.
+    os.environ['DATASTORE_PROJECT_ID'] = 'project'
+    # Setting just a project id isn't enough info.
+    self.assertRaisesRegexp(ValueError,
+                            'Could not determine app id\..*',
+                            tasklets.make_default_context)
+    # Unless the override is specified.
+    os.environ['DATASTORE_USE_PROJECT_ID_AS_APP_ID'] = 'True'
+    ctx = tasklets.make_default_context()
+    self.assertEqual(datastore_rpc._CLOUD_DATASTORE_V1, ctx._conn._api_version)
+    os.environ['DATASTORE_APP_ID'] = 's~project'
+    # App id and override should not both be specified
+    self.assertRaisesRegexp(ValueError,
+                            'App id was provided .* but .* was set to true\.',
+                            tasklets.make_default_context)
+    del os.environ['DATASTORE_USE_PROJECT_ID_AS_APP_ID']
+    ctx = tasklets.make_default_context()
+    self.assertEqual(datastore_rpc._CLOUD_DATASTORE_V1, ctx._conn._api_version)
+    os.environ['DATASTORE_APP_ID'] = 's~anotherproject'
+    # The provided app id must resolve to the provided project id.
+    self.assertRaises(ValueError, tasklets.make_default_context)
+    os.environ['DATASTORE_APP_ID'] = 's~project'
+    os.environ['DATASTORE_ADDITIONAL_APP_IDS'] = 's~anotherapp,s~andanother'
+    ctx = tasklets.make_default_context()
+    converter = ctx._conn.adapter.get_entity_converter()
+    self.assertEquals('s~anotherapp', converter.project_to_app_id('anotherapp'))
+    self.assertEquals('s~andanother', converter.project_to_app_id('andanother'))
+
+  def testCloudDatastoreContextWithExistingApplicationId(self):
+    os.environ['DATASTORE_APP_ID'] = 's~project'
+    os.environ['DATASTORE_PROJECT_ID'] = 'project'
+    os.environ['APPLICATION_ID'] = 's~a-different-project'
+    # If things are set propertly but APPLICATION_ID is already set, we fail.
+    self.assertRaises(ValueError, tasklets.make_default_context)
+
+  def testContext_MemcacheUnavailable(self):
+    key = model.Key('Foo', 1)
+    ent = model.Expando(key=key, bar=1)
+    ctx = tasklets.get_context()
+    ctx.set_memcache_policy(True)
+    self.assertRaises(NotImplementedError, ctx.put(ent).get_result)
+
+  def testContext_TaskQueueUnavailable(self):
+    self.assertRaises(NotImplementedError, taskqueue.add, url='/')
+
+
 if __name__ == '__main__':
   unittest.main()
