draht provides process-level messaging.

$ npm install draht

The first thing you need to do is to integrate draht into your application. For that add a reference to the draht module.

const Draht = require('draht');

To access the global draht, you need to get the instance property:

const draht = Draht.instance;

If you need your own draht channel, create a new instance:

const draht = new Draht();

To emit an event, call the draht's emit function and provide the event name as well as its payload as parameters. Optionally, you may specify a callback.

draht.emit('foo', { bar: 'baz' }, () => {
  // ...
});

Please note that the emit function internally calls process.nextTick to make sure that an event is processed asynchronously.

You can also emit namespaced events. For that, prefix the event name with the namespace name and separate them by using the expression ::.

draht.emit('demo::foo', { bar: 'baz' }, () => {
  // ...
});

To subscribe to an event, call the on function and provide the name of the event you want to subscribe to as well as an event handling function.

draht.on('demo::foo', (evt, callback) => {
  // ...
});

Alternatively you may also use the once function to subscribe to an event and have the handler automatically removed afterwards.

draht.once('demo::foo', (evt, callback) => {
  // ...
});

If you want to receive all events within a specific namespace, you can use the * character.

draht.on('demo::*', (evt, callback) => {
  // ...
});

Nested namespaces are supported as well, but please note that when using wildcards you need to specify them for each namespace level separately. E.g., if you have events in the form foo::bar::baz and you would like to subscribe to any event in the foo namespace, use foo::*::*, not foo::*.

From time to time you need to unsubscribe from an event. For this use the removeListener function and provide the event name as well as the handler to remove. Please note that in this case you need to provide the very same handler instance to removeListener as you previously used.

const onFoo = function (evt, callback) {
  // ...
};

draht.on('demo::foo', onFoo);
// ...
draht.removeListener('demo::foo', onFoo);

To remove all listeners for an event use removeAllListeners and provide only the event name.

draht.removeAllListeners('demo::foo');

If you omit the event name, too, then all listeners for all events are unsubscribed.

draht.removeAllListeners();

To build this module use roboter.

$ bot

The MIT License (MIT) Copyright (c) 2013-2018 the native web.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

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