I am implementing the steps in the Quickstart.

I did notice another question on this. I double checked that env_variables section in app.yaml has the right values for ENDPOINTS_SERVICE_NAME and ENDPOINTS_SERVICE_VERSION.

../_ah/api/explorer doesn't show any endpoint under 'Services'.

What is this error and how to fix it?

Error log shows:

 (/base/data/home/runtimes/python27_experiment/python27_lib/versions/1/google/appengine/runtime/wsgi.py:263)
Traceback (most recent call last):File "/base/data/home/runtimes/python27_experiment/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 240, in Handlehandler = _config_handle.add_wsgi_middleware(self._LoadHandler())File "/base/data/home/runtimes/python27_experiment/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 299, in _LoadHandlerhandler, path, err = LoadObject(self._handler)File "/base/data/home/runtimes/python27_experiment/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 85, in LoadObjectobj = __import__(path[0])File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/main.py", line 103, in <module>api = endpoints.api_server([EchoApi])File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/lib/endpoints/apiserving.py", line 520, in api_servercontroller)File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/lib/google/api/control/wsgi.py", line 121, in add_alla_service = loader.load()File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/lib/google/api/control/service.py", line 110, in loadreturn self._load_func(**kw)File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/lib/google/api/config/service_config.py", line 78, in fetch_service_config_log_and_raise(Exception, message_template.format(status_code))File "/base/data/home/apps/s~test-app-129421/20170217t185546.399267289806711006/lib/google/api/config/service_config.py", line 126, in _log_and_raiseraise exception_class(message)
Exception: Fetching service config failed (status code 404)

I had the same Exception trace, except mine was a 403. Hope is helpful to others having the same frustration I had.

Exception: Fetching service config failed (status code 403)

I finally found that in my app.yaml it had this from the GIT clone

ENDPOINTS_SERVICE_NAME: echo-api.endpoints.[YOUR-PROJECT-ID].cloud.goog

And the Quickstart only directed me to replace YOUR-PROJECT-ID.

I had to also replace .cloud.goog with .appspot.com