Many Events

Listen to and send events.

Example:

const ManyEvents = require('many-events');

const eventBus = new ManyEvents();

// your event handler
function doSomething(data) {
  console.log(data);
}

// listen for the 'my-amazing-event' event
eventBus.on('my-amazing-event', doSomething);

// firing the event
eventBus.send('my-amazing-event', 'peanut butter'); // output -> peanut butter

Installation

npm i many-events

License

The project is licensed under the MIT license.

API

new ManyEvents(options)

The constructor for a new event bus.

• options: Object
  • The configuration object
• Returns: ManyEvents instance

Options object:

| Option | Effect | | --------------------------- | ------------------------------------------------------------------------------------------------------- | | suppressMissingHandlerError | Wether to suppress the error that is thrown if an event is fired without any handlers. (Default: false) |

ManyEvents.on(eventName, handler)

Adds an event listener to be executed when the event is fired.

• eventName: String

  • The event name.

• handler: Function

  • The function to be called when the event fires.

• Returns: void

ManyEvents.send(eventName, data)

Fires an event and sends data.

• eventName: String

  • The event to be fired.

• data: any

  • The data that will be passed to the handlers.

• Returns: void

ManyEvents.remove(eventName, handler)

Removes an event handler.

• eventName: String

  • The event name.

• handler: Function

  • A reference to the function to be removed.

• Returns: void

ManyEvents.removeAll(eventName)

Removes all handlers for an event.

• eventName: String

  • The event name.

• Returns: void

ManyEvents.use(eventName, middleware)

Add a middleware to an event. This middleware can modify data before it reaches the event handlers.

• eventName: String

  • The event to which the middleware will be attached.

• middleware: Function

  • The middleware to be added.

• Returns: void

ManyEvents.removeMiddleware(eventName, middleware)

Removes a middleware from an event.

• eventName: String

  • The event from which the middleware will be removed.

• middleware: Function

  • A reference to the middleware to be removed.

• Returns: void

ManyEvents.removeAllMiddleware(eventName)

Removes all middleware for an event.

• eventName: String

  • The event name.

• Returns: void

How a middleware looks

• The data argument will be either the original data sent by the event emitter or data modified by the previous middleware.

• The updateData function will replace the data with whatever you pass into it.

function middleware(data, updateData) {
  // This function will update the data that will be passed to the next middleware and event handlers
  updateData(data);
}