URL Fetch AssertionError: 2 - google-app-engine

Question

When using the asynchronous URL Fetch I get intermittent errors like this:
For 300 fetches I'm getting about 20 of theses. Am I doing something wrong? Or is this a bug?
Traceback (most recent call last):
File "/base/data/home/apps/s~culturemap-bulkmail/1.368407357562484358/bulkmail/views.py", line 83, in mailer
emailer.send(email, context)
File "/base/data/home/apps/s~culturemap-bulkmail/1.368407357562484358/bulkmail/mailers/amazon.py", line 91, in send
self.connection.send(email, msg.message().as_string())
File "/base/data/home/apps/s~culturemap-bulkmail/1.368407357562484358/bulkmail/mailers/amazon.py", line 49, in send
headers=self.headers,
File "/python27_runtime/python27_lib/versions/1/google/appengine/api/urlfetch.py", line 339, in make_fetch_call
rpc.make_call('Fetch', request, response, _get_fetch_result, allow_truncated)
File "/python27_runtime/python27_lib/versions/1/google/appengine/api/apiproxy_stub_map.py", line 519, in make_call
assert self.__rpc.state == apiproxy_rpc.RPC.IDLE, repr(self.state)
AssertionError: 2
in init:
self.fetcher = urlfetch.create_rpc(deadline=60)
in method that gets called several times:
also line that errors out:
fetch = urlfetch.make_fetch_call(
self.fetcher,
'https://email.us-east-1.amazonaws.com/',
payload=form_data,
method=urlfetch.POST,
headers=self.headers,
)
I guess I should create a new rpc instead of reusing it?

Answer 1

Show some of your code, from the error it looks like you're reusing an existing active RPC object.