channelpy 0.2

Prerequisite

Start a RabbitMQ instance by executing the following command in the root directory of this repository:

docker-compose up -d

Quickstart

• Create a channel with:

  >>> from channelpy import Channel
  >>> ch = Channel()

• Put and get objects to and from the channel:

  >>> ch.put('foo')
  >>> ch.get()
  'foo'
  >>> ch.get(timeout=1)
  # raises ChannelTimeoutException since channel is empty

• Pass channels into channels:

  >>> ch1 = Channel()
  >>> ch1.put(5)
  >>> ch2 = Channel()
  >>> ch2.put(ch1)
  >>> x = ch2.get()
  >>> x.get()
  5

• Channels can be instantiated by name:

  >>> ch = Channel()
  >>> ch.name
  'daa0a490f9254c69883335c9f925d74f'
  >>> another = Channel(name=ch.name)
  >>> another.put('foo')
  >>> ch.get()
  'foo'

  Or create them with a specific name:

  >>> ch = Channel(name='my_channel')

• Multiple consumers and producers can be attached to a channel. Messages are delivered in round-robin fashion to consumers. However, a close_all can be delivered to all the consumers to signal a full termination of the channel.

  >>> ch = Channel()
  >>> def f(c):
  ...     while True:
  ...         print(c.get())
  ...
  >>> threading.Thread(target=f, args=(ch,)).start()
  >>> threading.Thread(target=f, args=(ch,)).start()
  >>> ch.put(4)        # one of the threads will print 4
  >>> ch.close_all()   # ChannelClosedException is raised in all threads

• The broker to use can be configured at instantiation time or by using the config file ~/.channelpy.yml. For example:

  connection: RabbitConnection
    uri: amqp://192.168.35.10:5672

Tests

Run the tests with:

$ BROKER='amqp://localhost:5672' py.test -v

Implementation Details

To be written.