Integrate Twig with CodeIgniter 4

Question

I used Twig with Symfony and I really loved it. I now have a CodeIgniter project and I want to integrate Twig with it.

I installed the latest versions of CodeIgniter and Twig via Composer and and followed this tutorial but I believe the code in the tutorial is for CI v3.

Could anyone who has integrated Twig with CI v4 help me with the proper code please.

UPDATE

solution below!

Answer 1

I found the solution some time ago and I'm posting it in case some people stumble across the question.

1. First of all, all your controllers must extend BaseController; this controller is available by default when you install CodeIgniter 4.

2. Create a custom helper file and put in [project-name]/appstarter/app/Helpers.

IMPORTANT

• the name of your helper must be [name]_helper.php or it will not work!

for example mine is called custom_helper.php

3. Create the following function in the custom helper you just created:

    use Twig\Environment;
    use Twig\Extension\DebugExtension;
    use Twig\Loader\FilesystemLoader;
    use Twig\TwigFilter;
   
    if (!function_exists('twig_conf')) {
        function twig_conf() {
            // the follwing line of code is the only one needed to make Twig work
            // the lines of code that follow are optional
            $loader = new FilesystemLoader('Views', '../app/');
   
            // to be able to use the 'dump' function in twig files
            $twig = new Environment($loader, ['debug' => true]);
            $twig->addExtension(new DebugExtension());
   
            // twig lets you create custom filters            
            $filter = new TwigFilter('_base_url', function ($asset) {
                return base_url() . '/' . $asset;
            });
            $twig->addFilter($filter);
   
            return $twig;
        }
    }
   

NOTE

• before creating any custom filter, make sure Twig doesn't already has one built-in.

4. Now in the BaseController you'll find an empty array called $helpers. You must put the name of your custom helper in it. Mine is called custom_helper.php; so the code looks like this for me:

   protected $helpers = ['custom'];
   

5. Just below the array you'll find the constructor for BaseController and this is where the Twig library will be initialized; by calling the function you created in your custom helper:

   public function initController(RequestInterface $request, ResponseInterface $response, LoggerInterface $logger) {      
       parent::initController($request, $response, $logger);
   
       $this->twig = twig_conf();
   }
   

6. Now you are good to go! To render your twig files in any controller:

   return $this->twig->render('twig_name', $dataArray);