cluster: support options in Worker constructor

This commit moves some common Worker code into the constructor
via support for an options argument.

Reviewed-By: Fedor Indutny <fedor@indutny.com>

Author: cjihrig

lib/cluster.js

@@ -35,12 +35,24 @@ cluster.isWorker = ('NODE_UNIQUE_ID' in process.env);
 cluster.isMaster = (cluster.isWorker === false);
 
 
-function Worker() {
-  if (!(this instanceof Worker)) return new Worker;
+function Worker(options) {
+  if (!(this instanceof Worker))
+    return new Worker(options);
+
   EventEmitter.call(this);
+
+  if (!util.isObject(options))
+    options = {};
+
   this.suicide = undefined;
-  this.state = 'none';
-  this.id = 0;
+  this.state = options.state || 'none';
+  this.id = options.id | 0;
+
+  if (options.process) {
+    this.process = options.process;
+    this.process.on('error', this.emit.bind(this, 'error'));
+    this.process.on('message', this.emit.bind(this, 'message'));
+  }
 }
 util.inherits(Worker, EventEmitter);
 
@@ -190,26 +202,6 @@ if (cluster.isMaster)
 else
   workerInit();
 
-
-function createWorkerExecArgv(masterExecArgv, worker) {
-  var args = masterExecArgv.slice();
-  var debugPort = process.debugPort + worker.id;
-  var hasDebugArg = false;
-
-  for (var i = 0; i < args.length; i++) {
-    var match = args[i].match(/^(--debug|--debug-brk)(=\d+)?$/);
-    if (!match) continue;
-    args[i] = match[1] + '=' + debugPort;
-    hasDebugArg = true;
-  }
-
-  if (!hasDebugArg)
-    args = ['--debug-port=' + debugPort].concat(args);
-
-  return args;
-}
-
-
 function masterInit() {
   cluster.workers = {};
 
@@ -278,21 +270,46 @@ function masterInit() {
     });
   };
 
-  var ids = 0;
-  cluster.fork = function(env) {
-    cluster.setupMaster();
-    var worker = new Worker;
-    worker.id = ++ids;
+  function createWorkerProcess(id, env) {
     var workerEnv = util._extend({}, process.env);
+    var execArgv = cluster.settings.execArgv.slice();
+    var debugPort = process.debugPort + id;
+    var hasDebugArg = false;
+
     workerEnv = util._extend(workerEnv, env);
-    workerEnv.NODE_UNIQUE_ID = '' + worker.id;
-    worker.process = fork(cluster.settings.exec, cluster.settings.args, {
+    workerEnv.NODE_UNIQUE_ID = '' + id;
+
+    for (var i = 0; i < execArgv.length; i++) {
+      var match = execArgv[i].match(/^(--debug|--debug-brk)(=\d+)?$/);
+
+      if (match) {
+        execArgv[i] = match[1] + '=' + debugPort;
+        hasDebugArg = true;
+      }
+    }
+
+    if (!hasDebugArg)
+      execArgv = ['--debug-port=' + debugPort].concat(execArgv);
+
+    return fork(cluster.settings.exec, cluster.settings.args, {
       env: workerEnv,
       silent: cluster.settings.silent,
-      execArgv: createWorkerExecArgv(cluster.settings.execArgv, worker),
+      execArgv: execArgv,
       gid: cluster.settings.gid,
       uid: cluster.settings.uid
     });
+  }
+
+  var ids = 0;
+
+  cluster.fork = function(env) {
+    cluster.setupMaster();
+    var id = ++ids;
+    var workerProcess = createWorkerProcess(id, env);
+    var worker = new Worker({
+      id: id,
+      process: workerProcess
+    });
     worker.process.once('exit', function(exitCode, signalCode) {
       worker.suicide = !!worker.suicide;
       worker.state = 'dead';
@@ -307,8 +324,6 @@ function masterInit() {
       cluster.emit('disconnect', worker);
       delete cluster.workers[worker.id];
     });
-    worker.process.on('error', worker.emit.bind(worker, 'error'));
-    worker.process.on('message', worker.emit.bind(worker, 'message'));
     worker.process.on('internalMessage', internal(worker, onmessage));
     process.nextTick(function() {
       cluster.emit('fork', worker);
@@ -447,20 +462,19 @@ function workerInit() {
 
   // Called from src/node.js
   cluster._setupWorker = function() {
-    var worker = new Worker;
+    var worker = new Worker({
+      id: +process.env.NODE_UNIQUE_ID | 0,
+      process: process,
+      state: 'online'
+    });
     cluster.worker = worker;
-    worker.id = +process.env.NODE_UNIQUE_ID | 0;
-    worker.state = 'online';
-    worker.process = process;
     process.once('disconnect', function() {
       if (!worker.suicide) {
         // Unexpected disconnect, master exited, or some such nastiness, so
         // worker exits immediately.
         process.exit(0);
       }
     });
-    worker.process.on('error', worker.emit.bind(worker, 'error'));
-    worker.process.on('message', worker.emit.bind(worker, 'message'));
     process.on('internalMessage', internal(worker, onmessage));
     send({ act: 'online' });
     function onmessage(message, handle) {

test/simple/test-cluster-worker-constructor.js

@@ -0,0 +1,49 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// 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.
+
+
+// test-cluster-worker-constructor.js
+// validates correct behavior of the cluster.Worker constructor
+
+var common = require('../common');
+var assert = require('assert');
+var cluster = require('cluster');
+var worker;
+
+worker = new cluster.Worker();
+assert.equal(worker.suicide, undefined);
+assert.equal(worker.state, 'none');
+assert.equal(worker.id, 0);
+assert.equal(worker.process, undefined);
+
+worker = new cluster.Worker({
+  id: 3,
+  state: 'online',
+  process: process
+});
+assert.equal(worker.suicide, undefined);
+assert.equal(worker.state, 'online');
+assert.equal(worker.id, 3);
+assert.equal(worker.process, process);
+
+worker = cluster.Worker.call({}, {id: 5});
+assert(worker instanceof cluster.Worker);
+assert.equal(worker.id, 5);