DeadlineExceededError not caught in try catch

Question

I recently enclosed a function call inside a try-catch block to catch all URL Fetch exceptions but as per logs below it did not get caught.

from google.appengine.api import urlfetch_errors 
:: 
:: 
try: 
    gitkit_user     = gitkit_instance.VerifyGitkitToken (self.request.cookies['gtoken']) 
except ( urlfetch_errors.DeadlineExceededError, urlfetch_errors.ConnectionClosedError, urlfetch_errors.DNSLookupFailedError, urlfetch_errors.DownloadError, urlfetch_errors.Error, urlfetch_errors.InternalTransientError, urlfetch_errors.InvalidMethodError, urlfetch_errors.InvalidURLError, urlfetch_errors.MalformedReplyError, urlfetch_errors.PayloadTooLargeError, urlfetch_errors.ResponseTooLargeError, urlfetch_errors.SSLCertificateError, urlfetch_errors.TooManyRedirectsError ): 

    logging.error ("Exception occurred while executing gitkit_instance.VerifyGitkitToken (). \nDetails: "+traceback.format_exc ()) 

Error log including trace

The API call urlfetch.Fetch() took too long to respond and was cancelled.
Traceback (most recent call last):
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 1535, in __call__
    rv = self.handle_exception(request, response, e)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 1529, in __call__
    rv = self.router.dispatch(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 1278, in default_dispatcher
    return route.handler_adapter(request, response)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 1102, in __call__
    return handler.dispatch()
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 572, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "/base/data/home/runtimes/python27/python27_lib/versions/third_party/webapp2-2.5.2/webapp2.py", line 570, in dispatch
    return method(*args, **kwargs)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/ext/ndb/tasklets.py", line 1057, in add_context_wrapper
    return synctaskletfunc(*args, **kwds)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/ext/ndb/tasklets.py", line 1038, in synctasklet_wrapper
    return taskletfunc(*args, **kwds).get_result()
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/ext/ndb/tasklets.py", line 1011, in tasklet_wrapper
    result = func(*args, **kwds)
  File "/base/data/home/apps/s~myapp/1.389163610985502634/main_v3.py", line 29956, in get
    gitkit_user     = gitkit_instance.VerifyGitkitToken (self.request.cookies['gtoken'])
  File "/base/data/home/apps/s~myapp/1.389163610985502634/gitkitclient.py", line 216, in VerifyGitkitToken
    certs = self.rpc_helper.GetPublicCert()
  File "/base/data/home/apps/s~myapp/1.389163610985502634/rpchelper.py", line 159, in GetPublicCert
    resp, content = self.http.request(cert_url, headers=headers)
  File "/base/data/home/apps/s~myapp/1.389163610985502634/httplib2/__init__.py", line 1570, in request
    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
  File "/base/data/home/apps/s~myapp/1.389163610985502634/httplib2/__init__.py", line 1317, in _request
    (response, content) = self._conn_request(conn, request_uri, method, body, headers)
  File "/base/data/home/apps/s~myapp/1.389163610985502634/httplib2/__init__.py", line 1286, in _conn_request
    response = conn.getresponse()
  File "/base/data/home/runtimes/python27/python27_dist/lib/python2.7/gae_override/httplib.py", line 522, in getresponse
    **extra_kwargs)
  File "/base/data/home/apps/s~myapp/1.389163610985502634/httplib2/__init__.py", line 1089, in fixed_fetch
    validate_certificate=validate_certificate)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/urlfetch.py", line 271, in fetch
    return rpc.get_result()
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 613, in get_result
    return self.__get_result_hook(self)
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/urlfetch.py", line 378, in _get_fetch_result
    rpc.check_success()
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 579, in check_success
    self.__rpc.CheckSuccess()
  File "/base/data/home/runtimes/python27/python27_lib/versions/1/google/appengine/api/apiproxy_rpc.py", line 134, in CheckSuccess
    raise self.exception
DeadlineExceededError: The API call urlfetch.Fetch() took too long to respond and was cancelled.

I am using Google App Engine with Python.
What did I do wrong ?

Answer 1

This might not entirely answer your question, but why not do something like this:

try: 
    gitkit_user = gitkit_instance.VerifyGitkitToken (self.request.cookies['gtoken']) 
except Exception as e:
    logging.error ("Exception occurred while executing gitkit_instance.VerifyGitkitToken (). \nDetails: " + e) 

The error will catch and the type of error will be printed (e).