Update

app/Http/Middleware/HorizonBasicAuthMiddleware.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\App;
+
+class HorizonBasicAuthMiddleware
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param  \Closure(\Illuminate\Http\Request): (\Symfony\Component\HttpFoundation\Response)  $next
+     */
+    public function handle($request, Closure $next)
+    {
+        // Skip auth check if not in production environment
+        if (! App::environment('production')) {
+            return $next($request);
+        }
+
+        $authenticationHasPassed = false;
+
+        if ($request->header('PHP_AUTH_USER', null) && $request->header('PHP_AUTH_PW', null)) {
+            $username = $request->header('PHP_AUTH_USER');
+            $password = $request->header('PHP_AUTH_PW');
+
+            if ($username === config('horizon.basic_auth.username') && $password === config('horizon.basic_auth.password')) {
+                $authenticationHasPassed = true;
+            }
+        }
+
+        if ($authenticationHasPassed === false) {
+            return response()->make('Invalid credentials.', 401, ['WWW-Authenticate' => 'Basic']);
+        }
+
+        return $next($request);
+    }
+}