AppPresser add Featured Images to Post Detail View

apppresser-featured-images.php

<?php

/*
Plugin Name: AppPresser Featured Images
Plugin URI: http://apppresser.com
Description: Add featured images to single posts in the app.
Version: 0.1
Author: AppPresser Team
Author URI: https://apppresser.com
License: GPLv2
*/

/**
* Use an AppPresser template hook
*/
add_action( 'rest_api_init', 'sb_register_template_hook' );
function sb_register_template_hook() {
    register_rest_field( 'post', // any post type registered with API
        'appp',
        array(
            'get_callback'    => 'sb_get_hook_data',
            'update_callback' => null,
            'schema'          => null,
        )
    );
}


/**
 * Get the value of a meta field field
 *
 * @param array $object Details of current post.
 * @param string $field_name Name of field.
 * @param WP_REST_Request $request Current request
 *
 * @return mixed
 */
function sb_get_hook_data( $object, $field_name, $request ) {
	
	$data = [];
    
    // uncomment these lines to add the post date
    // $data['post_detail']['below_title'] = '<div class="post-date">' . get_the_time('F j, Y', $object['id']) . '</div>';
    // $data['post_list']['below_title'] = '<div class="post-date">' . get_the_time('F j, Y', $object['id']) . '</div>';
    
    // this adds the post thumbnail to post detail views
	$data['post_detail']['above_title'] = '<div class="post-featured-wrap">' . get_the_post_thumbnail( $object['id'], 'large', array( 'class' => 'post-featured' ) ) . '</div>';	
	return $data;
}