A statically typed interface definition containing various types and call signatures is included as TypeScript interfaces in this project and serve as normative reference in addition to this document. Additionally, a unit test suite is avaible which also defines the behaviour of a correct implementation.
PubSub/A- this specification- PubSubImplementation - an implementation implementing this specification
Publish/Subscribe operations are always specific to the PubSubImplementation instances they are created on. That means that different PubSubImplementation instances MUST NOT trigger subscriptions when published on a different instance.
Example:
var instance1 = new PubSubImplementation();
var instance2 = new PubSubImplementation();
instance1.subscribe('topic', function() {
// if we reach this, your implementation is faulty
throw Execption('implementation is faulty!');
});
instance2.publish('topic', {});This does not apply to network enabled implementations where instances may exist across different machines. In networking scenarios, two instances on different machines are considered the same instance if they share the same backend server, and may be identified by a unique string such as an URI endpoint.
Channels are setup up asynchronously:
var pubsub = new PubSubImplementation();
var channel;
pubsub.channel('myChannel', function(channel) {
channel.publish('topic', arg);
});.channel() also returns a Promise, so instead of a callback one can simply:
pubsub.channel().then(function(channel) {
channel.publish('topic', arg);
});