prevent downgrade from https to http

also ensures site is always accessed in https

app/Http/Kernel.php

@@ -21,6 +21,7 @@ class Kernel extends HttpKernel
         \Illuminate\Foundation\Http\Middleware\ValidatePostSize::class,
         \App\Http\Middleware\TrimStrings::class,
         \Illuminate\Foundation\Http\Middleware\ConvertEmptyStringsToNull::class,
+        \App\Http\Middleware\StrictTransportSecurity::class
     ];
 
     /**

app/Http/Middleware/StrictTransportSecurity.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+class StrictTransportSecurity
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param \Closure(\Illuminate\Http\Request): (\Symfony\Component\HttpFoundation\Response) $next
+     */
+    public function handle(Request $request, Closure $next): Response
+    {
+        $response = $next($request);
+
+        $response->headers->set('Strict-Transport-Security', 'max-age=63072000; includeSubDomains; preload');
+
+        return $response;
+    }
+}