auto-detect locale based on browser preferences

app/Http/Middleware/SetLocale.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+
+class SetLocale
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @return mixed
+     */
+    public function handle(Request $request, Closure $next)
+    {
+        if (!session()->has('locale')) {
+            session()->put('locale', $request->getPreferredLanguage(
+                config('app.available_locales')
+            ));
+        }
+
+        app()->setLocale(session('locale'));
+
+        return $next($request);
+    }
+}

bootstrap/app.php

@@ -1,5 +1,6 @@
 <?php
 
+use App\Http\Middleware\SetLocale;
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Configuration\Exceptions;
 use Illuminate\Foundation\Configuration\Middleware;
@@ -12,7 +13,7 @@ return Application::configure(basePath: dirname(__DIR__))
         health: '/up',
     )
     ->withMiddleware(function (Middleware $middleware) {
-        //
+        $middleware->append(SetLocale::class);
     })
     ->withExceptions(function (Exceptions $exceptions) {
         //

config/app.php

@@ -77,6 +77,7 @@ return [
     | set to any locale for which you plan to have translation strings.
     |
     */
+    'available_locales' => ['en', 'es'],
 
     'locale' => env('APP_LOCALE', 'en'),