The handle_message method of provider is never executed

#1

Hi,

I’m trying to consume amqp messages by following the Example in nameko.messaging module,but failed.

@consume(queue = queue)
def handle_message(self, message):

I found that the messages are received,and handle_message is spawned in spawn_managed_thread(nameko/containers.py),but isn’t executed for some reason,which I tried very hard but failed to figure out.

The following is what I get by adding “print(fn)” in spawn_managed_thread method:
functools.partial(<bound method Consumer.handle_message of <Consumer [LibvirtCIKojiWatcherService.handle_message] at 0x7fa6ec8f6b50>>, {‘mlist’: {‘list_name’: ‘package-announce’}, ‘msg’: {‘archived-at’: ‘https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/J5IAOAVQXTSTN67OMO3L4HSZB4RQP27Y/’, ‘cc’: None, ‘delivered-to’: None, ‘from’: ‘updates@fedoraproject.org’, ‘in-reply-to’: None, ‘message-id’: ‘20201230013913.4130330A5C71@bastion01.iad2.fedoraproject.org’, ‘references’: None, ‘subject’: ‘Fedora 33 Update: golang-github-pborman-uuid-1.2.1-1.fc33’, ‘to’: ‘package-announce@lists.fedoraproject.org’, ‘user-agent’: None, ‘x-mailman-rule-hits’: ‘nonmember-moderation’, ‘x-mailman-rule-misses’: ‘dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-config-1; header-match-config-2; header-match-config-3’, ‘x-message-id-hash’: ‘J5IAOAVQXTSTN67OMO3L4HSZB4RQP27Y’}}, <Message object at 0x7fa6ec88f9d0 with details {‘state’: ‘RECEIVED’, ‘content_type’: ‘application/json’, ‘delivery_tag’: 2, ‘body_length’: 828, ‘properties’: {}, ‘delivery_info’: {‘exchange’: ‘zmq.topic’, ‘routing_key’: ‘org.fedoraproject.prod.mailman.receive’}}>)

#2

What are you expecting to happen that is not happening?

It certainly looks like your message is being received. If you replace your print(fn) with a pdb.set_trace(), or put one in LibvirtCIKojiWatcherService.handle_message, you should be able to step through what is actually happening.

If you can provide example code to reproduce that would be helpful too.

#3

Hi,

What are you expecting to happen that is not happening?

I add one print line at the beginning of LibvirtCIKojiWatcherService.handle_message,
it’s not printed,I also add pdb.set_trace() at the beginning,and the program didn’t stop.

If you can provide example code to reproduce that would be helpful too

Here is the code link:

Just pip install it,and execute"koji-watcher --email-notify --registry Openshift"

You need to add the code in my PR to have it work:)

#4

I think the problem here is that you’re never calling eventlet.monkey_patch.

See the note at the bottom of the docs here about that.

The monkey patch gives Eventlet the ability to switch threads when something blocks for I/O. Without it, threads will block. Essentially your service is deadlocked.

Make sure to apply the monkey patch before any imports, otherwise you don’t import the patched versions.

#5

Yes,after adding eventlet.monkey_patch, my problem is solved,thanks for your information and help.
Would you please review my PR[1] when you get some time to spare?Thanks.

[1]provide a way to config login_method by skycastlelily · Pull Request #713 · nameko/nameko · GitHub