RabbitMQ python library check status

Question

Folks, I am trying to check connections that error out, and log to alert if that happens.

credentials = pika.PlainCredentials(username, password)
parameters = pika.ConnectionParameters(
    credentials=credentials,
    host='localhost',
    port=tcpport,
    virtual_host='/vhost')
if pika.BlockingConnection(parameters):
    log_error("RabbitMQ Accepts non-SSL Connections")
else:
    log_info("RabbitMQ Not accepting non-SSL connections")

For some reason, this is not working, and is spitting out:

WARNING:pika.adapters.base_connection:Connection to 127.0.0.1:8080 failed: [Errno 111] Connection refused
Traceback (most recent call last):
  File "./rabbit_test.py", line 141, in <module>
    main()
  File "./rabbit_test.py", line 129, in main
    check_non_ssl('username', 'password')
  File "./rabbit_test.py", line 40, in check_non_ssl
    if pika.BlockingConnection(parameters):
  File "/usr/lib/python2.6/site-packages/pika/adapters/blocking_connection.py", line 107, in __init__
    super(BlockingConnection, self).__init__(parameters, None, False)
  File "/usr/lib/python2.6/site-packages/pika/adapters/base_connection.py", line 62, in __init__
    on_close_callback)
  File "/usr/lib/python2.6/site-packages/pika/connection.py", line 590, in __init__
    self.connect()
  File "/usr/lib/python2.6/site-packages/pika/adapters/blocking_connection.py", line 206, in connect
    if not self._adapter_connect():
  File "/usr/lib/python2.6/site-packages/pika/adapters/blocking_connection.py", line 275, in _adapter_connect
    raise exceptions.AMQPConnectionError(1)
pika.exceptions.AMQPConnectionError: 1

How can I catch failures and alert on them and continue my checks, instead of the script breaking out?

Thanks!

Answer 1

Instead of if/else clause, which evaluates the statement as boolean, you can use try and except to catch errors:

try:
    pika.BlockingConnection(parameters)
    log_error("RabbitMQ Accepts non-SSL Connections")
except: # if the anything goes wrong, go here
    log_info("RabbitMQ Not accepting non-SSL connections")