Response Headers :

        X-Powered-By: PHP/8.2.16
    

You must add the APP_KEY from your .env file into the vercel.json configuration. To do this, you need to set the APP_KEY in the env section of the vercel.json file. First, generate your APP_KEY using the command php artisan key:generate and then copy the generated key into the vercel.json file like this:

 {
     "version": 2,
     "framework": null,
     "functions": {
         "api/index.php": { "runtime": "vercel-php@0.6.0" }
     },
     "routes": [
         {
             "src": "/(.*)",
             "dest": "/api/index.php"
         },
         {
             "src": "/(.*)",
             "dest": "public/$1"
         }
     ],
     "env": {
         "APP_ENV": "production",
         "APP_DEBUG": "true",
         "APP_URL": "https://yourprojectdomain.com",

         // Add your APP_KEY here
         "APP_KEY": "",
         // Add your APP_KEY here

         "APP_CONFIG_CACHE": "/tmp/config.php",
         "APP_EVENTS_CACHE": "/tmp/events.php",
         "APP_PACKAGES_CACHE": "/tmp/packages.php",
         "APP_ROUTES_CACHE": "/tmp/routes.php",
         "APP_SERVICES_CACHE": "/tmp/services.php",
         "VIEW_COMPILED_PATH": "/tmp",
 
         "CACHE_DRIVER": "array",
         "LOG_CHANNEL": "stderr",
         "SESSION_DRIVER": "cookie"
     }
 }
    

Additionally, to set up the build and output settings in Vercel, make sure to:

• First, create a dist folder in the root directory of your Laravel project. This folder will be used to store any build files or assets that will be served by Vercel.
• Open your Laravel project, then go to Settings > General, and under the Build & Development Settings section, enable and set the Output Directory to public to ensure that the built files are served from the correct directory.
• In Vercel, still within the General tab, scroll down to find Node.js Version and set it to 18.x or higher (but not the latest version). This is important for compatibility and stability with the packages and dependencies in your Laravel project.

To test your newly created REST API, you can visit the /api/api/message route on Vercel. If you configured the route as shown earlier, visiting https://laravel-vercel-preview.vercel.app/api/api/message will return a JSON response like this:

        {
            "X-Powered-By": "'PHP/' . phpversion()"
        }
    

However, when running the application locally, you only need to visit /api/message (without the extra /api prefix). This is because Vercel uses serverless functions with specific routing, whereas Laravel's local development server handles routes directly.