Add site health tests to your WordPress site health screen

demo-site-health.php

<?php
/**
 * Plugin Name:       Demo Site Health Test
 * Description:       Add site health tests to the WordPress site-health dashboard.
 * Version:           1.0.0
 * Requires at least: 5.1
 * Requires PHP:      5.6
 * Author:            thelovekesh
 * Author URI:        https://thelovekesh.com/
 * License:           GPL v2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Update URI:        https://example.com/my-plugin/
 * Text Domain:       lps
 *
 * @package thelovekesh/site-health-tests
 */

// Add site health tests in WordPress site-health dashboard.
add_filter(
	'site_status_tests',
	'thelovekesh_demo_site_health_test'
);

/**
 * Add site health tests.
 *
 * @param array $tests WordPress site-health tests.
 * @return array Tests
 */
function thelovekesh_demo_site_health_test( $tests ) {
	// @see <https://github.com/WordPress/WordPress/blob/master/wp-admin/includes/class-wp-site-health.php#L2429>.
	$tests['direct']['wp_demo_site_health_test'] = array(
		'label' => __( 'Demo Site Health Test', 'lps' ),
		'test'  => 'thelovekesh_demo_site_health_test_callback',
	);

	return $tests;
}

/**
 * Add site health tests callback.
 *
 * @return array Tests
 */
function thelovekesh_demo_site_health_test_callback() {
	// @see <https://github.com/WordPress/WordPress/blob/master/wp-admin/includes/class-wp-site-health.php#L170>.
	$results = array(
		'label'       => __( 'Demo Site Health Test', 'lps' ),
		'status'      => 'good',
		'badge'       => array(
			'label' => __( 'Demo Site Health Test', 'lps' ),
			'color' => 'green',
		),
		'description' => __( 'Add site health tests to the WordPress site-health dashboard.', 'lps' ),
		'actions'     => '',
		'test'        => 'wp_demo_site_health_test',
	);

	/*
	* You can evaluate the site health test results and change the status, badge, description, actions, etc.
	* And manipulate the site health test results array.
	*/

	// Change status to 'critical'.
	$results['status'] = 'critical';

	// Change badge color.
	$results['badge']['color'] = 'red';

	// Change description.
	$results['description'] = __( 'You have some critical issues with your site.', 'lps' );

	// Provide action where the critical issues can be fixed.
	$results['actions'] = sprintf(
		'<a href="%s">%s</a>',
		esc_url( admin_url( 'options-general.php' ) ),
		__( 'Fix critical issues', 'lps' )
	);

	return $results;
}