[PROTON-2469] How to use proton-python properly to receive messages

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Feedback Received
• Component/s: python-binding
• Assignee: Unassigned
• Reporter: Andreas Waider
• Created: 24/Nov/21 14:58
• Updated: 24/Nov/21 17:03
• Resolved: 24/Nov/21 16:57

Description

My configuration:
Running qpidd on host: 192.168.80.81 with following exchanges (`qpid-config exchanges`):
```
Type      Exchange Name       Attributes
==================================================
direct                        --replicate=none
direct    amq.direct          --durable --replicate=none
fanout    amq.fanout          --durable --replicate=none
headers   amq.match           --durable --replicate=none
topic     amq.topic           --durable --replicate=none
direct    qmf.default.direct  --replicate=none
topic     qmf.default.topic   --replicate=none
topic     qpid.management     --replicate=none
```

I have multiple producers publishing to the topics like `amq.topic/com.product.sample1`, `amq.topic/com.product.sample2`, you get the pattern.

I can receive all messages from the producers by running `qpid-receive -b 192.168.80.81 -a amq.topic/com.product.sample1 -f` on the commandline.

But when it comes to implementing this in Python using the [python-qpid-proton](https://pypi.org/project/python-qpid-proton/) library (version 0.35.0) it wont work as needed. This is my python file to receive messages on a specific topic:

```
from proton.handlers import MessagingHandler
from proton.reactor import Container

broker_url = "192.168.80.81:5672"
topic = "amq.topic/com.product.sample"

class Client(MessagingHandler):
    def _init_(self, broker_url, topic):
        super(Client, self)._init_()
        self.broker_url = broker_url
        self.topic = topic

    def on_start(self, event):
        conn = event.container.connect(self.broker_url)
        self.receiver = event.container.create_receiver(
            conn, self.topic, dynamic=True)

    def on_message(self, event):
        print(event.message.body)

Container(Client(broker_url, topic)).run()
```

Can anyone help me and point me to where my mistake is? Help is much appreciated!