Add example Webpack plugin for watching route files to Readme. Closes #…

…526.

README.md

@@ -23,6 +23,7 @@ Ziggy supports all versions of Laravel from `5.4` onward, and all modern browser
     - [Vue](#vue)
     - [React](#react)
     - [SPAs or separate repos](#spas-or-separate-repos)
+    - [Recompiling on route changes](#recompiling-on-route-changes)
 - [**Filtering Routes**](#filtering-routes)
     - [Basic Filtering](#basic-filtering)
     - [Filtering using Groups](#filtering-using-groups)
@@ -414,6 +415,32 @@ const Ziggy = await response.toJson();
 route('home', undefined, undefined, Ziggy);
 ```
 
+#### Recompiling on route changes
+
+If you're generating a `ziggy.js` file and using Laravel Mix, you can watch your route files and regenerate your Ziggy configuration when they change by adding a custom Webpack plugin like the one below to your build:
+
+```js
+// webpack.mix.js
+const { exec } = require('child_process');
+const { resolve } = require('path');
+const glob = require('glob');
+
+mix.webpackConfig({
+    plugins: [
+        {
+            apply: (compiler) => {
+                compiler.hooks.compilation.tap('WatchRoutesPlugin', (compilation) => {
+                    glob.sync('./routes/*.php').map(file => compilation.fileDependencies.add(resolve(file)));
+                });
+                compiler.hooks.afterDone.tap('ZiggyGeneratePlugin', () => {
+                    exec('php artisan ziggy:generate');
+                });
+            }
+        },
+    ],
+});
+```
+
 ## Filtering Routes
 
 Ziggy supports filtering the routes it makes available to your JavaScript, which is great if you have certain routes that you don't want to be included and visible in the source of the response sent back to clients. Filtering routes is optional—by default, Ziggy includes all your application's named routes.