master-cluster - npm Package Compare versions

Comparing version 0.2.0 to 0.3.0

master-cluster.js

 'use strict';
 
+var assert = require('assert');
 var cluster = require('cluster');
+var http = require('http');
+var os = require('os');
 var debug = require('debug')('master-cluster');
 var reloader = require('./reloader');
+
 var setup = {};
+var noop = function () {}
 
 function start (options) {
-  if (! cluster.isMaster) throw new Error('Start can only be run on master!');
+  assert(cluster.isMaster, 'Start can only be run on master!');
+
   options = options || {};
   if (options.isCluster === false) {
-    setup = options;
-    if (options.exec) require(options.exec);
+    assert(options.exec, 'exec option must be specified to run in non-cluster mode');
+
+    require(options.exec);
     return;
   }
-  if (! options.size) options.size = require('os').cpus().length;
+  if (! options.size) options.size = os.cpus().length;
   setup.logger = options.logger;
@@ -21,3 +28,3 @@
 
-  var counter = 0;
+  var counterReloadWorkerFails = 0;
   var reload = options.reload || options.reload === false ? options.reload : /^dev/.test(process.env.NODE_ENV);
@@ -27,6 +34,2 @@
     reloader.reload(options);
-    cluster.reset = function () {
-      eachCluster(options.size, fork);
-      counter = 0;
-    }
   }
@@ -36,2 +39,6 @@
 
+  cluster.on('fork', function (worker) {
+    debug('Worker forked, id %d', worker.id);
+  });
+
   cluster.on('disconnect', function (worker) {
@@ -43,11 +50,14 @@ debug('Worker %d with pid %s disconnected', worker.id, worker.process.pid);
     }
-    if (counter > options.size * 3) {
+    if (counterReloadWorkerFails > options.size * 3) {
       logError('Application is crashing. Waiting for file change.');
       return;
     }
-    if (counter === 0)
+    if (counterReloadWorkerFails === 0)
+      // reset `counterReloadWorkerFails` in reload mode
+      // if there's no errors for more than 2 seconds
       setTimeout(function () {
-        counter = 0;
+        counterReloadWorkerFails = 0;
       }, 2000);
-    counter++;
+
+    counterReloadWorkerFails++;
     fork();
@@ -76,17 +86,14 @@ });
 function run () {
-  if (typeof setup.run === 'undefined') throw new Error('There is nothing to run!');
-  if (typeof setup.error === 'undefined') setup.error = function () {};
+  assert(cluster.isWorker, 'run can be executed only inside worker process');
+  assert(typeof setup.run === 'function', 'There is nothing to run!');
 
-  var d = require('domain').create(), args = arguments;
-  d.on('error', onWorkerError);
-  for (var i = 0; i < arguments.length; i++) d.add(arguments[i]);
-  d.run(function () {
-    setup.run.apply(this, args);
-  });
+  if (typeof setup.error === 'undefined') setup.error = noop;
+  setup.run.apply(null, arguments);
 }
 
-function createHttpServer (handler, port, onShutdown) {
-  var http = require('http');
+function createHttpServer (handler, port, onShutdown, onListening) {
   setFnHandlers (handler, onShutdown);
-  return http.createServer(run).listen(port);
+
+  if (!onListening) onListening = noop;
+  return http.createServer(run).listen(port, onListening);
 }
@@ -96,3 +103,3 @@
   setup.run = runFn;
-  setup.error = errorFn || function () {};
+  setup.error = errorFn || noop;
   return this;
@@ -99,0 +106,0 @@ }

package.json

@@ -5,3 +5,3 @@ {
   "description": "Facilitate using cluster and domain modules, live reload application in development mode on code change.",
-  "version": "0.2.0",
+  "version": "0.3.0",
   "dependencies": {
@@ -8,0 +8,0 @@ "debug": "^2.0.0",

README.md

@@ -5,4 +5,3 @@ # master-cluster
 in any project. I created this module as I use the cluster module in pretty much all my projects and wanted to
-remove the boilerplate code. It implements node.js core [domain](http://nodejs.org/api/domain.html) module
-for correct exception handling. It also provides hot reloading of files on the worker in development mode
+remove the boilerplate code. It also provides hot reloading of files on the worker in development mode
 so that workers are restarted when code is changed.
@@ -28,4 +27,3 @@
     // create the server and pass MC run handler
-    // each request will be wrap in a domain for exception handling
-    // so that workers are restarted automatically on crash
+    // workers are restarted automatically on crash
     var server = http.createServer(MC.run);
@@ -57,3 +55,5 @@ server.listen(3000, function () {
 
-    MC.createHttpServer(app.index, 3000, shutdown);
+    MC.createHttpServer(app.index, 3000, shutdown, function () {
+      console.log("Listening on %d", 3000);
+    });
 
@@ -85,6 +85,7 @@ function shutdown () {
 
-- `exec`: the code to run on the cluster master
+- `exec`: file path to worker file (see `exec` option of [cluster.setupMaster](https://nodejs.org/api/cluster.html#cluster_cluster_setupmaster_settings))
 - `size`: the number of workers to start, default is `require("os").cpus().length`
-- `reload`: `boolean`, default is `false` except when `process.env.NODE_ENV == 'dev'`
+- `reload`: `boolean`, default is `false` except when `/^dev/.test(process.env.NODE_ENV)`
 - `logger`: optional logger for errors (must implement `error` method)
+- `isCluster`: pass `false` to disable `cluster` and run master-only process. Setting `exec` is required in this case
 
@@ -95,2 +96,3 @@ Reloader specific options:
 - `extensions`: file extensions to watch for and reload on change, default to `js`
+- `path`: path to watch for change, default to current directory (`.`)
 
@@ -105,10 +107,10 @@ Worker options:
 - `start (options)`: start the master with cluster options
-- `run ()`: worker http handler that runs the request wrapped in the domain error handling
-- `setFnHandlers (runFn, errorFn)`: set the run and error handlers for the domain module
+- `run ()`: worker http handler that runs the request
+- `setFnHandlers (runFn, errorFn)`: set the run and error handlers
 - `setOptions (options)`: set the options for the workers (logger and kill timeout)
-- `createHttpServer (handler, port, onShutdown)`: create the http server and setup the run and error handlers for the domain module
+- `createHttpServer (handler, port, onShutdown, onListening)`: create the http server and setup the run and error handlers
 
 ### Miscellaneous
 
-- `cluster`: expose the exported cluster module
+- `cluster`: expose node.js [cluster](https://nodejs.org/api/cluster.html) module
 
@@ -115,0 +117,0 @@ # Disclaimer

No alert changes

Improved metrics

Total package byte prevSize

13520

increased by2.84%

Lines of code

221

increased by0.45%

Number of lines in readme file

123

increased by1.65%

No dependency changes