Count downloads of files from the WordPress Media Library

count-download

<?php
if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly

global $download_base_dir;
$download_base_dir = dirname(__FILE__);

global $download_prefix;
$download_prefix = 'download_';

function gr_download_init() {
    add_meta_box( 'gr_download_shortcode_box', __( 'Insert a download link', 'green' ), 'gr_download_meta_box_shortcode', 'attachment', 'side', 'high' );
}
function gr_download_meta_box_shortcode() {
	global $post;
	echo '<p>'. __('To automatically count downloads, please use this shortcode:', 'green') .'</p>';
		echo '<p><span class="showcase-code">[download id="'. $post->ID .'"]'. __('Click here to download', 'green') .'[/download]</span>';
	echo '</p>';
}
add_action('admin_init', 'gr_download_init');

function gr_download_create_field($form_fields, $post) {
	global $post;
	if ( is_object( $post ) ) {
		$form_fields['download-download-count'] = array(
			'label' => __('Downloads', 'green'),
			'input' => 'text', 
			'value' => get_post_meta( $post->ID ,'_download-download-count', TRUE ),
		);
	}
	return $form_fields;
}
add_filter("attachment_fields_to_edit", "gr_download_create_field", null, 2);

function gr_download_save_field($post, $attachment) {
	if( isset($attachment['download-download-count']) ){
		$attach = sanitize_text_field( $attachment['download-download-count'] );
		update_post_meta( $post['ID'], '_download-download-count', $attach );
	}
	return $post;
}
add_filter('attachment_fields_to_save', 'gr_download_save_field', null , 2);

function gr_download_shortcode($atts, $content = null) {
	extract(shortcode_atts(array(
		"id" => ''
	), $atts));
	return '<a href="'.site_url().'?download='.$id.'">'.$content.'</a>';
}
add_shortcode("download", "gr_download_shortcode"); 

function gr_download_shortcode_show($atts) {
	extract(shortcode_atts(array(
		"id" => ''
	), $atts));
	return get_post_meta( $id, '_download-download-count', TRUE );
}
add_shortcode("download_show", "gr_download_shortcode_show"); 

if( !is_admin() ) {
	if( isset($_GET['download']) AND is_numeric($_GET['download']) ) {
		$count     = get_post_meta($_GET['download'], '_download-download-count', TRUE);
		$count     = sanitize_text_field( $count );
		update_post_meta($_GET['download'], '_download-download-count', $count+1);
		$file      = wp_get_attachment_url( $_GET['download'] );
		$file_name = basename($file);
		if ( isset($file) ) {
			$wp_upload_dir      = wp_upload_dir(); 
			$current_upload_dir = $wp_upload_dir['path']; 
			$filepath           = $current_upload_dir.'/'.$file_name;
			switch(strtolower(substr(strrchr($file_name,'.'),1))) {
				case 'pdf':  $mime = 'application/pdf'; break;
				case 'zip':  $mime = 'application/zip'; break;
				case 'jpeg': $mime = 'image/jpg';       break;
				case 'jpg':  $mime = 'image/jpg';       break;
				case 'png':  $mime = 'image/jpg';       break;
				default:     $mime = 'application/force-download';
			}
			header('Pragma: public');
			header('Expires: 0');
			header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
			header('Cache-Control: private',FALSE);
			header('Content-Type: '. $mime);
			header('Content-Disposition: attachment; filename="'. basename($file_name) .'"');
			header('Content-Transfer-Encoding: binary');
			header('Connection: close');

			$access_type = NULL;
			if ( function_exists('get_filesystem_method') ) {
				$access_type = get_filesystem_method();
			}
			if ( $access_type === 'direct' ) {
				
				$creds = request_filesystem_credentials( site_url() . '/wp-admin/', '', false, false, array() );

				if ( !WP_Filesystem( $creds ) ) {
					return false;
				}
				
				global $wp_filesystem;
				
				echo $wp_filesystem->get_contents( $file );
				
			} else {
				
				readfile( $file );
				
			}

			exit();
		}
	}
}

Hi

I am interested in this code that you have kindly provided and I have some questions:

1. Will it work with the latest WordPress 5.3.2?
2. How do I use this code? It doesn't look like it is a plugin. Do I add it to my child theme functions.php?
3. Where do you see the download counts? In the media library back-end?

Thanks for your clarification.

Andrew