add wp-rocket

wp-content/plugins/wp-rocket/inc/front/deferred-js.php

@@ -0,0 +1,59 @@
+<?php
+
+defined( 'ABSPATH' ) || exit;
+
+/**
+ * Defer all JS files.
+ *
+ * @since 2.10
+ * @author Remy Perona
+ *
+ * @param string $buffer HTML content.
+ * @return string Updated HTML content
+ */
+function rocket_defer_js( $buffer ) {
+	if ( ( defined( 'DONOTROCKETOPTIMIZE' ) && DONOTROCKETOPTIMIZE ) || ( defined( 'DONOTASYNCCSS' ) && DONOTASYNCCSS ) ) {
+		return;
+	}
+
+	if ( ! get_rocket_option( 'defer_all_js' ) ) {
+		return $buffer;
+	}
+
+	if ( is_rocket_post_excluded_option( 'defer_all_js' ) ) {
+		return $buffer;
+	}
+
+	$buffer_nocomments = preg_replace( '/<!--(.*)-->/Uis', '', $buffer );
+	// Get all JS files with this regex.
+	preg_match_all( '#<script\s+([^>]+[\s\'"])?src\s*=\s*[\'"]\s*?([^\'"]+\.js(?:\?[^\'"]*)?)\s*?[\'"]([^>]+)?\/?>#iU', $buffer_nocomments, $tags_match );
+
+	if ( ! isset( $tags_match[0] ) ) {
+		return $buffer;
+	}
+
+	$exclude_defer_js = implode( '|', get_rocket_exclude_defer_js() );
+
+	foreach ( $tags_match[0] as $i => $tag ) {
+		// Check if this file should be deferred.
+		if ( preg_match( '#(' . $exclude_defer_js . ')#i', $tags_match[2][ $i ] ) ) {
+			continue;
+		}
+
+		// Don't add defer if already async.
+		if ( false !== strpos( $tags_match[1][ $i ], 'async' ) || false !== strpos( $tags_match[3][ $i ], 'async' ) ) {
+			continue;
+		}
+
+		// Don't add defer if already defer.
+		if ( false !== strpos( $tags_match[1][ $i ], 'defer' ) || false !== strpos( $tags_match[3][ $i ], 'defer' ) ) {
+			continue;
+		}
+
+		$deferred_tag = str_replace( '>', ' defer>', $tag );
+		$buffer       = str_replace( $tag, $deferred_tag, $buffer );
+	}
+
+	return $buffer;
+}
+add_filter( 'rocket_buffer', 'rocket_defer_js', 24 );