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Python AMQP 0.9.1 client library

Build status coverage BSD License Python AMQP can be installed via wheel Supported Python versions. Support Python implementations.

Version:5.3.1
Web:https://amqp.readthedocs.io/
Download:https://pypi.org/project/amqp/
Source:http://github.com/celery/py-amqp/
Keywords:amqp, rabbitmq

About

This is a fork of amqplib which was originally written by Barry Pederson. It is maintained by the Celery project, and used by kombu as a pure python alternative when librabbitmq is not available.

This library should be API compatible with librabbitmq.

Differences from amqplib

  • Supports draining events from multiple channels (Connection.drain_events)

  • Support for timeouts

  • Channels are restored after channel error, instead of having to close the connection.

  • Support for heartbeats

    • Connection.heartbeat_tick(rate=2) must called at regular intervals (half of the heartbeat value if rate is 2).
    • Or some other scheme by using Connection.send_heartbeat.
  • Supports RabbitMQ extensions:
    • Consumer Cancel Notifications
      • by default a cancel results in ChannelError being raised
      • but not if a on_cancel callback is passed to basic_consume.
    • Publisher confirms
      • Channel.confirm_select() enables publisher confirms.
      • Channel.events['basic_ack'].append(my_callback) adds a callback to be called when a message is confirmed. This callback is then called with the signature (delivery_tag, multiple).
    • Exchange-to-exchange bindings: exchange_bind / exchange_unbind.
      • Channel.confirm_select() enables publisher confirms.
      • Channel.events['basic_ack'].append(my_callback) adds a callback to be called when a message is confirmed. This callback is then called with the signature (delivery_tag, multiple).
    • Authentication Failure Notifications
      Instead of just closing the connection abruptly on invalid credentials, py-amqp will raise an AccessRefused error when connected to rabbitmq-server 3.2.0 or greater.

  • Support for basic_return

  • Uses AMQP 0-9-1 instead of 0-8.
    • Channel.access_request and ticket arguments to methods removed.
    • Supports the arguments argument to basic_consume.
    • internal argument to exchange_declare removed.
    • auto_delete argument to exchange_declare deprecated
    • insist argument to Connection removed.
    • Channel.alerts has been removed.
    • Support for Channel.basic_recover_async.
    • Channel.basic_recover deprecated.
  • Exceptions renamed to have idiomatic names:
    • AMQPException -> AMQPError
    • AMQPConnectionException -> ConnectionError``
    • AMQPChannelException -> ChannelError``
    • Connection.known_hosts removed.
    • Connection no longer supports redirects.
    • exchange argument to queue_bind can now be empty to use the "default exchange".

  • Adds Connection.is_alive that tries to detect whether the connection can still be used.

  • Adds Connection.connection_errors and .channel_errors, a list of recoverable errors.

  • Exposes the underlying socket as Connection.sock.

  • Adds Channel.no_ack_consumers to keep track of consumer tags that set the no_ack flag.

  • Slightly better at error recovery

Quick overview

Simple producer publishing messages to test queue using default exchange:

import amqp

with amqp.Connection('broker.example.com') as c:
    ch = c.channel()
    ch.basic_publish(amqp.Message('Hello World'), routing_key='test')

Producer publishing to test_exchange exchange with publisher confirms enabled and using virtual_host test_vhost:

import amqp

with amqp.Connection(
    'broker.example.com', exchange='test_exchange',
    confirm_publish=True, virtual_host='test_vhost'
) as c:
    ch = c.channel()
    ch.basic_publish(amqp.Message('Hello World'), routing_key='test')

Consumer with acknowledgments enabled:

import amqp

with amqp.Connection('broker.example.com') as c:
    ch = c.channel()
    def on_message(message):
        print('Received message (delivery tag: {}): {}'.format(message.delivery_tag, message.body))
        ch.basic_ack(message.delivery_tag)
    ch.basic_consume(queue='test', callback=on_message)
    while True:
        c.drain_events()

Consumer with acknowledgments disabled:

import amqp

with amqp.Connection('broker.example.com') as c:
    ch = c.channel()
    def on_message(message):
        print('Received message (delivery tag: {}): {}'.format(message.delivery_tag, message.body))
    ch.basic_consume(queue='test', callback=on_message, no_ack=True)
    while True:
        c.drain_events()

Speedups

This library has experimental support of speedups. Speedups are implemented using Cython. To enable speedups, CELERY_ENABLE_SPEEDUPS environment variable must be set during building/installation. Currently speedups can be installed:

  1. using source package (using --no-binary switch):
CELERY_ENABLE_SPEEDUPS=true pip install --no-binary :all: amqp
  1. building directly source code:
CELERY_ENABLE_SPEEDUPS=true python setup.py install

Further

py-amqp as part of the Tidelift Subscription

The maintainers of py-amqp and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. [Learn more.](https://tidelift.com/subscription/pkg/pypi-amqp?utm_source=pypi-amqp&utm_medium=referral&utm_campaign=readme&utm_term=repo)