Installation

From your application directory:

composer require dereuromark/cakephp-ajax

Loading the plugin is optional for Composer-autoloaded classes and aliases. Load it if you want its bootstrap to register the .json routing extension:

bin/cake plugin load Ajax

For selected route scopes, register extensions in config/routes.php instead:

$routes->scope('/', function (\Cake\Routing\RouteBuilder $builder): void {
    $builder->setExtensions(['json']);
    $builder->fallbacks();
});

Then load Ajax.Ajax in the controllers that need automatic response handling. See Getting started for an example using fetch().