Allow to apply arbitrary plugins when compiling ServiceWorker script

Author: akihikodaki

docs/options.md

@@ -131,6 +131,10 @@ _Example:_ `{ credentials: 'include' }`
 * **`minify`**: `boolean`. If set to `true` or `false`, the `ServiceWorker`'s output will be minified or not accordingly. If set to something else, the `ServiceWorker` output will be minified **if** you are using `webpack.optimize.UglifyJsPlugin` in your configuration.  
 _Default:_ `null`
 
+* **`plugins`**: `Array`. The plugins which will be applied when compling the `ServiceWorker`'s script.
+_Default:_ `undefined` (this option is no-op.)
+_Example:_ `[new require('webpack').DefinePlugin({ CAT: 'MEOW' })]`
+
 * **[Deprecated]** `navigateFallbackURL`: `string`. The URL that should be returned from the cache when a requested navigation URL isn't available on the cache or network. Similar to the `AppCache.FALLBACK` option.  
 _Example:_ `navigateFallbackURL: '/'`
 

lib/index.js

@@ -69,6 +69,11 @@ var OfflinePlugin = (function () {
       AppCache: false
     });
 
+    if (options.ServiceWorker && options.ServiceWorker.plugins) {
+      // plugins are class instances and should not be modified.
+      this.options.ServiceWorker.plugins = options.ServiceWorker.plugins;
+    }
+
     this.hash = null;
     this.assets = null;
     this.hashesMap = null;

lib/service-worker.js

@@ -46,6 +46,7 @@ var ServiceWorker = (function () {
 
     // Tool specific properties
     this.entry = options.entry;
+    this.plugins = options.plugins;
     this.scope = options.scope ? options.scope + '' : void 0;
     this.events = !!options.events;
     this.navigateFallbackURL = options.navigateFallbackURL;
@@ -126,6 +127,10 @@ var ServiceWorker = (function () {
         });
       }
 
+      this.plugins.forEach(function (plugin) {
+        return plugin.apply(childCompiler);
+      });
+
       // Needed for HMR. offline-plugin doesn't support it,
       // but added just in case to prevent other errors
       var compilationFn = function compilationFn(compilation) {

src/index.js

@@ -30,6 +30,11 @@ export default class OfflinePlugin {
       AppCache: false
     });
 
+    if (options.ServiceWorker && options.ServiceWorker.plugins) {
+      // plugins are class instances and should not be modified.
+      this.options.ServiceWorker.plugins = options.ServiceWorker.plugins;
+    }
+
     this.hash = null;
     this.assets = null;
     this.hashesMap = null;

src/service-worker.js

@@ -26,6 +26,7 @@ export default class ServiceWorker {
 
     // Tool specific properties
     this.entry = options.entry;
+    this.plugins = options.plugins;
     this.scope = options.scope ? options.scope + '' : void 0;
     this.events = !!options.events;
     this.navigateFallbackURL = options.navigateFallbackURL;
@@ -104,6 +105,8 @@ export default class ServiceWorker {
       });
     }
 
+    this.plugins.forEach((plugin) => plugin.apply(childCompiler));
+
     // Needed for HMR. offline-plugin doesn't support it,
     // but added just in case to prevent other errors
     const compilationFn = (compilation) => {