dissemination


Lightweight event/command library created to replace Backbone.Radio in
projects ported from Backbone/Marionette to React.

Installation

``bash
npm install dissemination --save
`



Usage

- ES6:

`javascript
import dissemination from 'dissemination';
`

- require with Node.js:

`javascript
var dissemination = require('dissemination');
`

- in browser include dist/dissemination.js or dist/dissemination.min.js script:

`javascript
var dissemination = window.dissemination;
`

and then

`javascript
dissemination().on('event', function() { console.log('event is fired'); });
dissemination().fire('event');
`

Examples

$3

- get default channel (with application name):

`javascript
const c = dissemination();
`

- get named channel:

`javascript
const c = dissemination('myChannel');
`

- create channel directly:

`javascript
import { Channel } from 'dissemination';
const c = new Channel();
`



$3

- add event listener:

`javascript
const listener = () => { console.log('event is fired'); };
dissemination().on('event', listener);
`

- remove specific event listener:

`javascript
dissemination().off('event', listener);
`

- remove all event listeners for a given event:

`javascript
dissemination().off('event');
`

- fire event:

`javascript
dissemination().fire('event');
`

- fire event with parameters:

`javascript
const listener = params => {
console.log(params); // => { item: 1 }
};
dissemination().on('event', listener);
dissemination().fire('event', { item: 1 });
`

- add event listener with additional options:

`javascript
const listener = (params, options) => {
console.log(params); // => { item: 1 }
console.log(options); // => { message: 'hello world' }
};
dissemination().on('event', listener, {
message: 'hello world'
});
dissemination().fire('event', { item: 1 });
`

- add event listener that will be executed once:

`javascript
let count = 0;
const listener = () => { count += 1; };
dissemination().once('event', listener);
dissemination().fire('event');
dissemination().fire('event');
console.log(count); // => 1
`

- interrupt event listeners' execution chain:

`javascript
let result = 0;
const listener1 = () => { result += 1; return false; };
const listener2 = () => { result += 2; };
dissemination().on('event', listener1);
dissemination().on('event', listener2);
dissemination().fire('event');
console.log(result); // => 1
`

- check whether event listeners are registered:

`javascript
const listener = () => { console.log('event is fired'); };
dissemination().on('event', listener);
console.log(dissemination().listenersRegistered('event')); // => true
`



$3

- add command handler:

`javascript
const handler = () => { console.log('command is handled'); };
dissemination().handle('command', handler);
`

- remove specific command handler:

`javascript
dissemination().unhandle('command');
`

- execute command:

`javascript
dissemination().execute('command');
`

- execute command with response result:

`javascript
const handler = () => { return 1 };
dissemination().handle('command', handler);
console.log(dissemination().request('command')); // => 1
`

- add command handler with additional options:

`javascript
const positive = options => options.number >= 0;
dissemination().handle('positive', positive);
console.log(dissemination().request('positive', { number: 2 })); // => true
console.log(dissemination().request('positive', { number: -1 })); // => false
`

- check whether command handler is registered:

`javascript
const handler = () => { console.log('command is handled'); };
dissemination().handle('command', handler);
console.log(dissemination().handlerRegistered('command')); // => true
`



$3

- add EventMixin or/and CommandMixin to any custom object:

`javascript
import { EventMixin } from 'dissemination';
const events = Object.assign({}, EventMixin);
events.on('event', () => { console.log('event is fired'); });
events.fire('event');
`

`javascript
import { CommandMixin } from 'dissemination';
const commands = Object.assign({}, CommandMixin);
commands.handle('command', function() { return 'hello world'; });
console.log(commands.request('command')); // => 'hello world'
`

Building

In order to build library run:

npm run build



Testing

Run unit tests:

npm test

Run tests with coverage:

npm run test:coverage

In order to run tests with Coveralls locally you have to provide COVERALLS_REPO_TOKEN:

COVERALLS_REPO_TOKEN= npm run test:coverage



Contributing



Before making a pull request, please, be sure that you are starting from develop` branch.

License

MIT