emit-mapper v1.0.0

emit-mapper

Re-emit events while mapping them to new names.

Usage

var src = new EventEmitter();
var dest = new EventEmitter();
var events = {
  before: 'preload:before',
  success: 'preload:success',
  failure: 'preload:failure',
};

var cleanup = emitMapper(src, dest, events);

dest.on('preload:before', console.log);
dest.on('preload:success', console.log);
dest.on('preload:failure', console.log);

src.emit('before', 'some value');
src.emit('success', 1, 2, 3);
src.emit('failure', 'moduleName', new Error('some error'));

// No more events will be re-emitted after cleanup
cleanup();

src.emit('before', 'not re-emitted');

API

emitMapper(source, destination, eventMapping)

Takes a source EventEmitter, a destination EventEmitter, and an eventMapping object that maps source events to destination events. Whenever an event from the eventMapping object is emitted on source, a new event will be emitted on destination with the mapped named but containing all the same arguments.

Returns a cleanup method to remove all handlers registered for re-emitting.

Prior art

This module is heavily inspired by re-emitter but the ability to map event names to new names was needed. Also, this module supports back to node 0.10 while re-emitter only supports node LTS versions.

License

MIT