Channel creation hanging forever

[mehdigmira]

Hello,

I use a task queue framework that builds on top of amqpstorm, i've encountered cases where my process hangs forever. I think I've found the cause and think it's caused by amqpstorm. It would occur if we have a broken connection and try to open a channel with it. What happens inside amqpstorm code is:

• connection.channel() is called (amqpstorm/connection.py:167)
• a threading lock is then acquired (amqpstorm/connection.py:186)
• with lazy=False, we try to open the channel (amqpstorm/connection.py:191)
• channel.rpc_request is called (amqpstorm/channel.py:291)
• channel.rpc.get_request() is called (amqpstorm/channel.py:328)
• channel.rpc._wait_for_request() is called (amqpstorm/rpc.py:99)
• channel.check_for_errors() is called (amqpstorm/rpc.py:133)
• connection.check_for_errors() is called (amqpstorm/channel.py:209)
• the connection is invalid so connection.close() is called (amqpstorm/connection.py:209)
• connection._close_remaining_channels is called (amqpstorm/connection.py:230)
• channel.close is called (amqpstorm/connection.py:285)
• channel._on_close_impl is called (amqpstorm/channel.py:197) which is just connection._cleanup_channel
• connection._cleanup_channel tries to hold the same lock that already acquired, so it hangs forever

Do you acknowledge this sequence can cause an infinite hang ?

[eandersson]

Yea - I see how that could happen. Let me see if I can reproduce it.

[mehdigmira]

Thanks for the quick reply, do you intend to publish a new version on pypi ?

[eandersson]

Yes, but I usually give it a few days to make sure people can review the changes, assuming everything looks good I'll probably upload it in 1-3 days.

[eandersson]

The new build show be available on pypi now. Let me know if the issue persists.