Process Events

npm install process-events --save

Process events is a library from Node.js that can run custom events via forked processes and return there response as promise. This is useful when you have long running tasks and you don't what to lock your main application thread.

Examples

Main node process

var processEvents = require('process-events');
var childProcess = processEvents.processEvent('./processes/child.js');
 
childProcess.then(function (process) {
  // send data to child process
  return process.send('name', {a: 1, b: 2}).then(function (response) {
    // response from child process
    console.log(response);  // {a: 2, b: 1}
    return process.send('name', {a: 3, b: 4});
  }).then(function () {
    // response from child process
    console.log(response);  // {a: 4, b: 3}
    return process.close();
  });
});

File ./processes/child.js

var processChild = require('process-events').processChild();
 
// bind to custom event
processChild.bind('name', function (request) {
  // do some logic here
  // resolve event as promise
  return Promise.resolve({a: request.b, b: request.a});
});

API

Main process API.

var processEvent = require('process-events').processEvent;
var worker = processEvent(workerFilePath: string);

Method	Description
worker.isConnected(): boolean	Returns child process connection state.
worker.send(namespace: string, data: any?): Promise	Sends message to child process.
worker.close(): Promise	Close child process. Node that if you don't close your process node script will continue to run forever or until process gets killed.
worker.reopen(): Promise	Will reopen child process after it was killed.

Child process API.

var processChild = require('process-events').processChild;

Method	Description
processChild.bind(namespace: string, callback: Function)	Bind callback to child process worker. Callback can return string or a Promise - response will be send to main process.