Added index.js and package.json, updated README.md

README.md

@@ -1,2 +1,48 @@
 # webpack-bundle-update-hook-plugin
+
 Add a tapable 'bundle-update' hook to webpack. On bundle updates registered plugins get lists of new, changed and removed modules.
+
+This plugin can be useful in combination with [webpack-dev-middleware](https://github.com/webpack/webpack-dev-middleware) or [webpack-dev-server](https://github.com/webpack/webpack-dev-server). The plugin adds a new hook `bundle-update` to which other plugins can register. After each bundle update, registered plugins receive lists of new, changed and removed files.
+
+## Installation
+
+    npm install --save-dev webpack-bundle-update-hook-plugin
+
+## Usage
+
+Add the plugin to your `webpack.config.js` file:
+
+    var BundleUpdateHookPlugin = require('webpack-bundle-update-hook-plugin');
+
+    module.exports = {
+
+        // ...
+
+        plugins: [
+            // ...
+            new BundleUpdateHookPlugin()
+        ]
+
+    };
+
+Then use [webpack's Node.js API](https://webpack.github.io/docs/node.js-api.html) to get a compiler with this configuration. The compiler exposes the [tapable API](https://github.com/webpack/tapable) for registering plugins. With the webpack-bundle-update-hook-plugin you can now create plugins for the hook `bundle-update`:
+
+    var webpack = require('webpack');
+    var webpackConfig = require('./webpack.config');
+
+    var compiler = webpack(webpackConfig);
+
+    compiler.plugin('bundle-update', function (newModules, changedModules, removedModules, stats) {
+        // newModules, changedModules and removedModules are objects. The properties of the objects are module ids, the
+        // values of these properties are the corresponding module resources (= absolute module paths).
+
+        // stats is passed as is from the compilers 'done' plugin hook.
+
+        console.log('new modules: ', newModules);
+        console.log('changed modules: ', changedModules);
+        console.log('removed modules: ', removedModules);
+    });
+
+## License
+
+MIT (see LICENSE file)

index.js

@@ -0,0 +1,88 @@
+/**
+ * Create a new BundleUpdateHookPlugin instance.
+ * @param {Object.<string, boolean>} options Available options: { debug: true|false } (debug defaults to false)
+ * @constructor
+ */
+function BundleUpdateHookPlugin(options) {
+    options = options || {};
+    this.debug = options.debug || false;
+}
+
+/**
+ * Register the plugin on the 'done' hook.
+ * @param compiler
+ */
+BundleUpdateHookPlugin.prototype.apply = function(compiler) {
+
+    var that = this;
+    var prevModules;
+
+    // do our things after a compilation is done
+    compiler.plugin('done', function(stats) {
+
+        var debug = that.debug;
+
+        var currModules = {};
+        var newModules = {};
+        var changedModules = {};
+        var removedModules = {};
+
+        stats.compilation.modules.forEach(function (module) {
+            // skip modules which don't have a resource property (e.g. main module 0)
+            if (!module.resource) return;
+
+            currModules[module.id] = {
+                buildTimestamp: module.buildTimestamp,
+                resource: module.resource
+            };
+
+            // if prevModules exists, check if current module is new or has changed
+            if (prevModules) {
+                if (!prevModules[module.id]) {
+                    // current module is new
+                    if (debug) console.log('[webpack-bundle-update-hook-plugin] detected new module: ' +
+                        module.resource);
+                    newModules[module.id] = module.resource;
+                } else if (prevModules[module.id].buildTimestamp !== module.buildTimestamp) {
+                    // current module has changed
+                    if (debug) console.log('[webpack-bundle-update-hook-plugin] detected changed module: ' +
+                        module.resource);
+                    changedModules[module.id] = module.resource;
+                }
+            }
+        });
+
+        // if prevModules exists, check for removed modules
+        if (prevModules) {
+            Object.keys(prevModules).forEach(function (id) {
+                if (!currModules[id]) {
+                    // module was removed
+                    if (debug) console.log('[webpack-bundle-update-hook-plugin] detected removed module: ' +
+                        prevModules[id].resource);
+                    removedModules[id] = prevModules[id].resource;
+                }
+            });
+        }
+
+        prevModules = currModules;
+
+        var newModulesCount = Object.getOwnPropertyNames(newModules).length;
+        var changedModulesCount = Object.getOwnPropertyNames(changedModules).length;
+        var removedModulesCount = Object.getOwnPropertyNames(removedModules).length;
+
+        // if anything changed, emit bundle-update event
+        if (newModulesCount !== 0 || changedModulesCount !== 0 || removedModulesCount !== 0) {
+            if (debug) console.log('[webpack-bundle-update-hook-plugin] a new bundle was compiled (' +
+                newModulesCount + ' new, ' + changedModulesCount + ' changed, ' + removedModulesCount +
+                ' removed modules) - emitting bundle-update');
+            this.applyPlugins('bundle-update', newModules, changedModules, removedModules, stats);
+        } else {
+            if (debug) console.log('[webpack-bundle-update-hook-plugin] a new bundle was compiled but nothing changed' +
+                ' (this will always apply to the first compilation)');
+        }
+
+    });
+
+};
+
+module.exports = BundleUpdateHookPlugin;

package.json

@@ -0,0 +1,23 @@
+{
+  "name": "webpack-bundle-update-hook-plugin",
+  "version": "1.0.0",
+  "description": "Add a tapable 'bundle-update' hook to webpack. On bundle updates registered plugins get lists of new, changed and removed modules.",
+  "main": "index.js",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/skleeschulte/webpack-bundle-update-hook-plugin.git"
+  },
+  "keywords": [
+    "webpack",
+    "plugin",
+    "tapable",
+    "hook",
+    "bundle",
+    "update",
+    "new",
+    "changed",
+    "removed"
+  ],
+  "author": "Stefan Kleeschulte",
+  "license": "MIT"
+}