process-channel

This module facilitates event based communication between parent and child process.

Installation

npm install process-channel

Usage Example

worker.js

var ProcessChannel = require('../lib/process-channel').ProcessChannel;

var channelId = process.argv.pop()
var channel = new ProcessChannel(process, channelId);

channel.on('greet', function(name) {
  channel.send('response', 'Hello ' + name);
});

channel.send('ready');

server.js

var fork = require('child_process').fork;
var ProcessChannel = require('process-channel').ProcessChannel;

var channelId = 123;
var worker = fork(__dirname + "/worker.js", [channelId]);
var channel = new ProcessChannel(worker, channelId);

channel.once('response', function(greeting) {
  console.log(greeting);
  worker.kill();
});

channel.once('ready', function() {
  channel.send('greet', 'Alex');
});

This should print out Hello Alex.

API

ProcessChannel(process, channelId)

• process - Process is a process to send to and receive messages from. Typically server would pass in the forked process and the worker would pass in the current process.
• channelId - Number is a unique channel number that is the same on the server and worker. It's used to differentiate messages coming from multiple workers.

channel.send(type, data)

• type - String is event type/name.
• data - is stringified and sent to the other process.

channel.on(type, handler)

• type - String is event type/name.
• handler - function(data) is a callback function which receives data from the send method.

Testing

npm test

License

The MIT License (MIT)

Copyright 2014 Alex Gorbatchev

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.