compas_eve.memory

Classes

InMemoryTransport

InMemoryTransport(codec: MessageCodec | None = None, *args, **kwargs)

In-Memory transport is ideal for simple single-process apps and testing.

It will only distribute messages within the same process, not across different processes.

Parameters:

• codec (MessageCodec | None, default: None ) –

  The codec to use for encoding and decoding messages. If not provided, defaults to JsonMessageCodec.

Referenced by:

• API Reference  compas_eve Functions
  •  get_default_transport
  •  set_default_transport

Functions

advertise

advertise(topic: Topic)

Announce this code will publish messages to the specified topic.

This call has no effect on the in-memory transport.

on_ready

on_ready(callback: Callable)

In-memory transport is always ready, it will immediately trigger the callback.

publish

publish(topic: Topic, message: Message)

Publish a message to a topic.

Parameters:

• topic (Topic) –

  Instance of the topic to publish to.

• message (Message) –

  Instance of the message to publish.

subscribe

subscribe(topic: Topic, callback: Callable) -> str

Subscribe to a topic.

Every time a new message is received on the topic, the callback will be invoked.

Parameters:

• topic (Topic) –

  Instance of the topic to subscribe to.

• callback (Callable) –

  Callback to invoke whenever a new message arrives. The callback should receive only one msg argument, e.g. lambda msg: print(msg).

Returns:

• str –

  Returns an identifier of the subscription.

unadvertise

unadvertise(topic: Topic)

Announce that this code will stop publishing messages to the specified topic.

This call has no effect on the in-memory transport.

unsubscribe

unsubscribe(topic: Topic)

Unsubscribe from the specified topic.

Parameters:

• topic (Topic) –

  Instance of the topic to unsubscribe from.

unsubscribe_by_id

unsubscribe_by_id(subscribe_id: str)

Unsubscribe from the specified topic based on the subscription id.