forkfriend

dead simple worker child process manager. respawn children. load balance work amongst children.

forkfriend

dead simple worker process manager. respawn children. load balance work amongst children.

 
var forkfriend = require('friend');
var friend = forkfriend();
 
// make 3 somefriend.js worker with arguments 
friend.add('somefriend.js',['-a',1],3);
 
// workers for the same file get the same args as the first.  
// multiple calls to add add that many more to the pool 
friend.add('somefriend.js')
 
friend.send('hey one of you work on this');
 
friend.on('message',function(message,workername,worker){
  // message is the data the child sent. 
  // workername === 'somefriend.js' 
  // worker instanceof ChildProcess 
})
 
// when you are all done 
friend.stop();
 
 

forkfriend forkfriend(options)

  • options {} [optional]
    • respawnInterval
      • defaults to 500 ms. this is the max speed that new children will be spawned to prevent pegging the cpu on broken workers
    • maxQueue
      • defaults to 100. this is the maximum number of pending messages for workers that should be held while waiting for a functional worker to spawn. after this messages will be dropped but a drop event will be emitted so you application can choose how to handle the issue.
  • returns "friend" an EventEmitter

friend

  • add(script,arguments [optional],num [optional])
  • add(script,num [optional])
    • script is the path to the javascript file you want to fork
    • arguments are passed to fork as argv of your child process
    • the number of children you want to add to the pool. this is the same as calling add multiple times.
  • remove(script)
  • remove(script, num [optional])
  • remove(script,cp ChildProcess [optional])
    • remove a worker from the pool for script
    • if cp is provided this specifc child is removed
    • if num is provided
  • get(script)
    • get an array of the child processes in the pool for script
  • send (message, script [optional])
    • the message to send to one worker of each pool
    • send the message to a worker spawned from "script"
  • stop ()
    • stops the show. kills all child processes so your script can exit cleanly.
  • refork (script, cp ChildProcess [optional])
    • kill and start a specific worker or any in the pool

friend events

  • message (message,script,args,cp ChildProcess)
    • a worker has sent you a message
  • worker (script,args,cp ChildProcess)
    • a new worker has been forked for this script
  • worker-exit (code,script,args,cp ChildProcess)
    • a worker has exited. the friend will try to refork it
  • worker-disconnect (script,args,cp ChildProcess)
    • a child has closed its communication channel with this process. the friend will try to kill it.
  • worker-error (error,script,args,cp ChildProcess)
    • a worker has had an error event, the friend will try to refork it.
  • drop
    • too many messages could not be sent to the workers for this script.
 
process.on('message',function(data){
  // do somthing 
  // tell friend about it 
  process.send('hey i worked onn '+data);
});
 
 

let me know if this is helpful or if you have any issues.