use plugin version instead of filemtime() for resources (#326)

Resources of the same version should be the same, no matter if the files
are touched or the plugin is re-installed. There are even scenarios
where the modification time is not reliable.

Reduce overhead of accessing the file system and simply add the plugin's
version to scripts and styles.

Author: stklcode

cachify.php

@@ -41,6 +41,7 @@
 define( 'CACHIFY_DIR', __DIR__ );
 define( 'CACHIFY_BASE', plugin_basename( __FILE__ ) );
 define( 'CACHIFY_CACHE_DIR', WP_CONTENT_DIR . '/cache/cachify' );
+define( 'CACHIFY_VERSION', '2.4.1' );
 
 
 /* Hooks */

inc/class-cachify.php

@@ -340,15 +340,15 @@ public static function register_styles() {
 			'cachify-dashboard',
 			plugins_url( 'css/dashboard.min.css', CACHIFY_FILE ),
 			array(),
-			filemtime( plugin_dir_path( CACHIFY_FILE ) . 'css/dashboard.min.css' )
+			CACHIFY_VERSION
 		);
 
 		/* Register admin bar flush CSS */
 		wp_register_style(
 			'cachify-admin-bar-flush',
 			plugins_url( 'css/admin-bar-flush.min.css', CACHIFY_FILE ),
 			array(),
-			filemtime( plugin_dir_path( CACHIFY_FILE ) . 'css/admin-bar-flush.min.css' )
+			CACHIFY_VERSION
 		);
 	}
 
@@ -363,7 +363,7 @@ public static function register_scripts() {
 			'cachify-admin-bar-flush',
 			plugins_url( 'js/admin-bar-flush.min.js', CACHIFY_FILE ),
 			array(),
-			filemtime( plugin_dir_path( CACHIFY_FILE ) . 'js/admin-bar-flush.min.js' ),
+			CACHIFY_VERSION,
 			true
 		);
 	}