Event To Promise

This package is used to turn events into promises.

API

• EventToPromise(emitter, [throwEvents]) - Constructor.
• ep#promise(event, [timeout]) - Return a promise for event.
• ep#getEmitter(event, [timeout]) - Get emitter.

emitter - Event emitter.

throwEvents - promise method will throw those events emitted arguments if they are emitted.

timeout - Timeout in miliseconds.

Error Handling: promise method will throw only errors which can be an instance of EventToPromise.errors.Timeout or an object {event:emittedArgs, ...} containing errors from specified throw events in constructor.

Installation

npm i -s event-2-promise

Example

const EventToPromise = require('event-2-promise');
const net = require('net');

(async () => {
  const socket = new net.Socket();
  const socketEP = new EventToPromise(socket, ['error', 'close']);
  try {
    socket.connect(80, '123.123.123.123');
    const emittedArgsConnect = await socketEP.promise('connect', 2000);
    const emittedArgsData = await socketEP.promise('data', 5000);
  } catch (err) {
    socket.destroy();
    if (err instanceof EventToPromise.errors.Timeout) {
      if (err.getEvent() === 'connect') {
        console.log('connect event timeout');
      } else if (err.getEvent() === 'data') {
        console.log('data event timeout');
      }
    } else {
      // err is a json object containing:
      // event name as a key {String} and emitted arguments as value {Array}
      // in this case the key can only be 'error' or 'close' because those are the events
      // which were specified as throw events
      console.log(err);
    }
  }
})();