Is there an easy way to convert the Routes from the old string syntax to the newer callable syntax?

METHOD I :

You may use a script or a seeder to convert your routes from the old string syntax to the newer callable syntax :

<?php

use Illuminate\Support\Facades\Route;

$routes = Route::getRoutes();

foreach ($routes as $route) {
    $action = $route->getAction();

    if (isset($action['controller'])) {
        [$controller, $method] = explode('@', $action['controller']);
        $route->setAction([
            'uses' => [$controller, $method],
        ]);
    }
}

Route::save();

You can save this script as a PHP file and run it from the command line using the php command :

php convert-routes.php

METHOD II :

Or, you may use database seeder to achieve the same :

<?php

use Illuminate\Database\Seeder;
use Illuminate\Support\Facades\Route;

class ConvertRoutesSeeder extends Seeder
{
    public function run()
    {
        $routes = Route::getRoutes();

        foreach ($routes as $route) {
            $action = $route->getAction();

            if (isset($action['controller'])) {
                [$controller, $method] = explode('@', $action['controller']);
                $route->setAction([
                    'uses' => [$controller, $method],
                ]);
            }
        }

        Route::save();
    }
}

To use this seeder, save it to a file named ConvertRoutesSeeder.php in the database/seeds directory of your Laravel project. Then, add it to the DatabaseSeeder class's run() method like this:

<?php

use Illuminate\Database\Seeder;

class DatabaseSeeder extends Seeder
{
    public function run()
    {
        $this->call(ConvertRoutesSeeder::class);
    }
}

Don't forget to run the seeder:

php artisan db:seed --class=ConvertRoutesSeeder

Just adjust RouteServiceProvider.php and use as is.

<?php

namespace App\Providers;

use Illuminate\Cache\RateLimiting\Limit;
use Illuminate\Foundation\Support\Providers\RouteServiceProvider as ServiceProvider;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\RateLimiter;
use Illuminate\Support\Facades\Route;

class RouteServiceProvider extends ServiceProvider
{

    /**
     * The path to the "home" route for your application.
     *
     * Typically, users are redirected here after authentication.
     *
     * @var string
     */
    public const HOME = '/home';

    protected $namespace = 'App\Http\Controllers';

    /**
     * Define your route model bindings, pattern filters, and other route configuration.
     */
    public function boot(): void
    {
        $this->configureRateLimiting();

        $this->routes(function () {
            Route::middleware('api')
                    ->prefix('api')
                    ->group(base_path('routes/api.php'));

            Route::middleware('web')
                    ->namespace($this->namespace)
                    ->group(base_path('routes/web.php'));
        });
    }

    /**
     * Configure the rate limiters for the application.
     */
    protected function configureRateLimiting(): void
    {
        RateLimiter::for('api', function (Request $request) {
            return Limit::perMinute(60)->by($request->user()?->id ?: $request->ip());
        });
    }

}

thanks everyone, I ended up using Rector: https://github.com/rectorphp/rector with the extension package for Laravel: https://github.com/driftingly/rector-laravel

Has anyone heard of it? I heard about it today for the first time (both Rector and the extension package).

I ran it and it updated the entire web.php to the new syntax quickly after setting up a config file and running the script.

Just in case, I copied the entire project, installed the extensions there and ran it, then copied the web.php back to the original project