Skip to content

Instantly share code, notes, and snippets.

@tim-smart
Created February 7, 2010 02:46
Show Gist options
  • Save tim-smart/297155 to your computer and use it in GitHub Desktop.
Save tim-smart/297155 to your computer and use it in GitHub Desktop.
Node.js Web Workers
// The main node process
// Will output to shell:
// {
// "test": "test"
// }
// "bam"
var worker = require('./webworker'),
sys = require('sys');
var testWorker = new worker.Worker(__dirname + '/usage_worker.js');
testWorker.addListener('message', function(data) {
sys.puts(sys.inspect(data));
});
testWorker.addListener('error', function(data) {
sys.puts(sys.inspect(data));
});
setTimeout(function() {
testWorker.postMessage("bam");
}, 2000);
// The worker node process
var worker = require('./webworker');
var emitter = worker.workerOpenStdio();
emitter.addListener('message', function(data) {
worker.postMessage(data);
});
worker.postMessage({test: "test"});
// A Web Worker implementation for Node.js
var events = require('events');
var Worker = exports.Worker = function(filepath) {
process.mixin(this, events.EventEmitter.prototype);
arguments = Array.prototype.slice.call(arguments);
try {
this._child = process.createChildProcess('node', arguments);
} catch (e) {
this.emit('error', 'webworker.Worker: Failed to create child process. ' + e.toString(), filepath, null);
return;
}
var self = this;
this._child.addListener('output', function(data) {
if (null === data)
self.emit.call(self, 'exit');
try {
data = JSON.parse(data);
self.emit.call(self, 'message', data);
} catch (e) {
self.emit.call(self, 'error', 'webworker.onmessage: Failed due to invalid response. ' + e.toString(), filepath, null);
}
});
this._child.addListener('error', function(data) {
if ('string' === typeof data) {
self.emit.call(self, 'error', data, filepath, null);
} else
self.emit.call(self, 'error', 'webworker.onerror: Failed due to invaild response. ', filepath, null);
});
};
Worker.prototype = {
postMessage: function(data) {
try {
data = JSON.stringify(data);
this._child.write(data);
} catch (e) {
this.emit('error', 'webworker.postMessage: Failed due to invalid data. ' + e.toString(), __filename, null);
}
},
terminate: function() {
this._child.kill();
}
};
exports.postMessage = function(data) {
try {
data = JSON.stringify(data);
process.stdio.write(data);
} catch (e) {
process.stdio.writeError('webworker.postMessage: Failed due to invalid data. ' + e.toString());
}
};
exports.workerOpenStdio = function() {
process.stdio.open();
var emitter = new events.EventEmitter();
process.stdio.addListener('data', function(data) {
try {
data = JSON.parse(data);
emitter.emit('message', data);
} catch (e) {
emitter.emit('error', 'webworker.workerOpenStdio: Failed to parse incoming message.' + e.toString());
}
});
return emitter;
};
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment