plz, show me to run minify in codeigniter 4

PHP Code:

//minify html output on codeigniter 4
if (ENVIRONMENT !== 'development')
    {
    Events::on('post_controller_constructor', function () {


        while (ob_get_level() > 0)
        {
            ob_end_flush();
        }

        ob_start(function ($buffer) {
            $search = array(
                '/\n/',      // replace end of line by a <del>space</del> nothing , if you want space make it down ' ' instead of ''
                '/\>[^\S ]+/s',    // strip whitespaces after tags, except space
                '/[^\S ]+\</s',    // strip whitespaces before tags, except space
                '/(\s)+/s',    // shorten multiple whitespace sequences
                '/<!--(.|\s)*?-->/' //remove HTML comments
            );

            $replace = array(
                '',
                '>',
                '<',
                '\\1',
                ''
            );

            $buffer = preg_replace($search, $replace, $buffer);
            return $buffer;
        });

Code:

<?php



namespace Config;



use CodeIgniter\Events\Events;

use CodeIgniter\Exceptions\FrameworkException;



/*

 * --------------------------------------------------------------------

 * Application Events

 * --------------------------------------------------------------------

 * Events allow you to tap into the execution of the program without

 * modifying or extending core files. This file provides a central

 * location to define your events, though they can always be added

 * at run-time, also, if needed.

 *

 * You create code that can execute by subscribing to events with

 * the 'on()' method. This accepts any form of callable, including

 * Closures, that will be executed when the event is triggered.

 *

 * Example:

 *      Events::on('create', [$myInstance, 'myMethod']);

 */



Events::on('pre_system', static function () {

    if (ENVIRONMENT !== 'testing') {

        if (ini_get('zlib.output_compression')) {

            throw FrameworkException::forEnabledZlibOutputCompression();

        }



        while (ob_get_level() > 0) {

            ob_end_flush();

        }



        ob_start(static fn ($buffer) => $buffer);

    }

//minify html output on codeigniter 4

if (ENVIRONMENT !== 'development')

    {

    Events::on('post_controller_constructor', function () {





        while (ob_get_level() > 0)

        {

            ob_end_flush();

        }



        ob_start(function ($buffer) {

            $search = array(

                '/\n/',      // replace end of line by a <del>space</del> nothing , if you want space make it down ' ' instead of ''

                '/\>[^\S ]+/s',    // strip whitespaces after tags, except space

                '/[^\S ]+\</s',    // strip whitespaces before tags, except space

                '/(\s)+/s',    // shorten multiple whitespace sequences

                '/<!--(.|\s)*?-->/' //remove HTML comments

            );



            $replace = array(

                '',

                '>',

                '<',

                '\\1',

                ''

            );



            $buffer = preg_replace($search, $replace, $buffer);

            return $buffer;

        });

    });

};



    /*

    * --------------------------------------------------------------------

    * Debug Toolbar Listeners.

    * --------------------------------------------------------------------

    * If you delete, they will no longer be collected.

    */

    if (CI_DEBUG && ! is_cli()) {

        Events::on('DBQuery', 'CodeIgniter\Debug\Toolbar\Collectors\Database::collect');

        Services::toolbar()->respond();

    }

});