A pika BlockingConnection attempt failed (pika version 1.0.0). The exception shown in the application log - adapters.utils.connection_workflow.AMQPConnectorStackTimeout - doesn't appear to be any of the exceptions in pika.exceptions.
Isn't pika supposed to convert internal exceptions such as this into one of those in pika.exceptions before surfacing it to the caller?
If not, how should I go about enumerating all the possible exceptions pika could raise so that I can decide which the caller can handle and which it should not attempt to handle? (Essentially, the caller needs to decide whether to exit on a non-recoverable exception or try again if the condition is probably transient.)
Maybe I've misinterpreted the application log, which is as follows:
2019-04-26T11:33:29.880310567Z ERROR:pika.adapters.utils.connection_workflow:Timeout while setting up AMQP to '█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False
2019-04-26T11:33:29.880880966Z ERROR:pika.adapters.utils.connection_workflow:AMQPConnector - reporting failure: AMQPConnectorAMQPHandshakeError: AMQPConnectorStackTimeout("Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', █)); ssl=False",)
2019-04-26T11:33:29.881053365Z ERROR:pika.adapters.utils.connection_workflow:AMQP connection workflow failed: AMQPConnectionWorkflowFailed: 1 exceptions in all; last exception - AMQPConnectorAMQPHandshakeError: AMQPConnectorStackTimeout("Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False",); first exception - None.
2019-04-26T11:33:29.881150165Z ERROR:pika.adapters.utils.connection_workflow:AMQPConnectionWorkflow - reporting failure: AMQPConnectionWorkflowFailed: 1 exceptions in all; last exception - AMQPConnectorAMQPHandshakeError: AMQPConnectorStackTimeout("Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False",); first exception - None
2019-04-26T11:33:29.881503064Z ERROR:pika.adapters.blocking_connection:Connection workflow failed: AMQPConnectionWorkflowFailed: 1 exceptions in all; last exception - AMQPConnectorAMQPHandshakeError: AMQPConnectorStackTimeout("Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False",); first exception - None
2019-04-26T11:33:29.882705661Z ERROR:pika.adapters.blocking_connection:Error in _create_connection().
2019-04-26T11:33:29.882720061Z Traceback (most recent call last):
2019-04-26T11:33:29.882724561Z File "/usr/lib/python3.6/site-packages/pika/adapters/blocking_connection.py", line 451, in _create_connection
2019-04-26T11:33:29.882728961Z raise self._reap_last_connection_workflow_error(error)
2019-04-26T11:33:29.882732761Z pika.adapters.utils.connection_workflow.AMQPConnectorStackTimeout: Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False
2019-04-26T11:33:29.883257859Z ERROR:root:AMQPConnectorStackTimeout Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False
2019-04-26T11:33:29.883273859Z Traceback (most recent call last):
2019-04-26T11:33:29.883278359Z File "main.py", line 143, in <module>
2019-04-26T11:33:29.883282559Z main()
2019-04-26T11:33:29.883286259Z File "main.py", line 118, in main
2019-04-26T11:33:29.883290059Z with pika.BlockingConnection(parameters=pika.URLParameters(██████████)) as connection:
2019-04-26T11:33:29.883293959Z File "/usr/lib/python3.6/site-packages/pika/adapters/blocking_connection.py", line 360, in __init__
2019-04-26T11:33:29.883307559Z self._impl = self._create_connection(parameters, _impl_class)
2019-04-26T11:33:29.883311659Z File "/usr/lib/python3.6/site-packages/pika/adapters/blocking_connection.py", line 451, in _create_connection
2019-04-26T11:33:29.883315459Z raise self._reap_last_connection_workflow_error(error)
2019-04-26T11:33:29.883319059Z pika.adapters.utils.connection_workflow.AMQPConnectorStackTimeout: Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False
2019-04-26T11:33:29.883323159Z Traceback (most recent call last):
2019-04-26T11:33:29.883326759Z File "main.py", line 143, in <module>
2019-04-26T11:33:29.883465559Z main()
2019-04-26T11:33:29.883473059Z File "main.py", line 118, in main
2019-04-26T11:33:29.883635558Z with pika.BlockingConnection(parameters=pika.URLParameters(██████████)) as connection:
2019-04-26T11:33:29.883650458Z File "/usr/lib/python3.6/site-packages/pika/adapters/blocking_connection.py", line 360, in __init__
2019-04-26T11:33:29.883894657Z self._impl = self._create_connection(parameters, _impl_class)
2019-04-26T11:33:29.883902657Z File "/usr/lib/python3.6/site-packages/pika/adapters/blocking_connection.py", line 451, in _create_connection
2019-04-26T11:33:29.884212657Z raise self._reap_last_connection_workflow_error(error)
2019-04-26T11:33:29.884222357Z pika.adapters.utils.connection_workflow.AMQPConnectorStackTimeout: Timeout during AMQP handshake'█.█.█.█'/(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '█.█.█.█', ('█.█.█.█', ████)); ssl=False
I had this problem again and found my own question :-)
The documentation seems a bit lacking, but there is a whole hierarchy of exceptions in pika.adapters.utils.connection_workflow, the base class of which is AMQPConnectorException.
The answer seems to be to browse this module source to see which exceptions ought to be handled.