cfork

cluster fork and restart easy way.

Easy fork with worker file path
Handle worker restart, event it was exit unexpected.
Auto error log process uncaughtException event

Install

$ npm install cfork --save

Usage

Example

var cfork = require('cfork');
var util = require('util');

cfork({
  exec: '/your/app/worker.js',
  // slaves: ['/your/app/slave.js'],
  // count: require('os').cpus().length,
})
.on('fork', function (worker) {
  console.warn('[%s] [worker:%d] new worker start', Date(), worker.process.pid);
})
.on('disconnect', function (worker) {
  console.warn('[%s] [master:%s] wroker:%s disconnect, suicide: %s, state: %s.',
    Date(), process.pid, worker.process.pid, worker.suicide, worker.state);
})
.on('exit', function (worker, code, signal) {
  var exitCode = worker.process.exitCode;
  var err = new Error(util.format('worker %s died (code: %s, signal: %s, suicide: %s, state: %s)',
    worker.process.pid, exitCode, signal, worker.suicide, worker.state));
  err.name = 'WorkerDiedError';
  console.error('[%s] [master:%s] wroker exit: %s', Date(), process.pid, err.stack);
})

// if you do not listen to this event
// cfork will output this message to stderr
.on('unexpectedExit', function (worker, code, signal) {
  // logger what you want
});

// emit when reach refork times limit
.on('reachReforkLimit', function () {
  // do what you want
});

// if you do not listen to this event
// cfork will listen it and output the error message to stderr
process.on('uncaughtException', function (err) {
  // do what you want
});

Options

exec : exec file path
slaves : slave process config
args : exec arguments
count : fork worker nums, default is os.cpus().length
refork : refork when worker disconnect or unexpected exit, default is true
limit: limit refork times within the duration, default is 60
duration: default is 60000, one minute (so, the refork times < limit / duration)
autoCoverage: auto fork with istanbul when running_under_istanbul env set, default is false

License

(The MIT License)

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.