Automatically mark GA4 scripts as being PX-verified

includes/amp-helper-functions.php

@@ -1546,6 +1546,9 @@ function amp_get_content_sanitizers( $post = null ) {
 		// from getting removed in PWA plugin offline/500 templates.
 		AMP_PWA_Script_Sanitizer::class            => [],
 
+		// The AMP_GTag_Script_Sanitizer runs before AMP_Script_Sanitizer to mark the the Google Analytics script tags as being PX-verified.
+		AMP_GTag_Script_Sanitizer::class           => [],
+
 		// The AMP_Script_Sanitizer runs here because based on whether it allows custom scripts
 		// to be kept, it may impact the behavior of other sanitizers. For example, if custom
 		// scripts are kept then this is a signal that tree shaking in AMP_Style_Sanitizer cannot be
@@ -1716,6 +1719,7 @@ function amp_get_content_sanitizers( $post = null ) {
 		AMP_Core_Theme_Sanitizer::class, // Must come before script sanitizer since onclick attributes are removed.
 		AMP_Bento_Sanitizer::class, // Bento scripts may be preserved here.
 		AMP_PWA_Script_Sanitizer::class, // Must come before script sanitizer since PWA offline page scripts are removed.
+		AMP_GTag_Script_Sanitizer::class, // Must come before script sanitizer since gtag.js is removed.
 		AMP_Script_Sanitizer::class, // Must come before sanitizers for images, videos, audios, comments, forms, and styles.
 		AMP_Form_Sanitizer::class, // Must come before comments sanitizer.
 		AMP_Comments_Sanitizer::class, // Also must come after the form sanitizer.

includes/sanitizers/class-amp-gtag-script-sanitizer.php

@@ -0,0 +1,87 @@
+<?php
+/**
+ * GA4 Script Sanitizer.
+ *
+ * - This sanitizer will facilitate using GA4 while waiting on an AMP implementation.
+ * - This sanitizer will be only used in Moderate or Loose sandboxing level
+ *
+ * @since 2.3.1
+ * @package AMP
+ */
+
+use AmpProject\AmpWP\Option;
+use AmpProject\AmpWP\ValidationExemption;
+
+/**
+ * Class AMP_GTag_Script_Sanitizer
+ *
+ * @since 2.3.1
+ * @internal
+ */
+class AMP_GTag_Script_Sanitizer extends AMP_Base_Sanitizer {
+
+	/**
+	 * Sanitize the AMP response for GA4 scripts.
+	 *
+	 * @since 2.3.1
+	 */
+	public function sanitize() {
+		if ( ! AMP_Options_Manager::get_option( Option::SANDBOXING_ENABLED ) ) {
+			return;
+		}
+
+		$sandboxing_level = AMP_Options_Manager::get_option( Option::SANDBOXING_LEVEL );
+
+		if ( 1 !== $sandboxing_level && 2 !== $sandboxing_level ) {
+			return;
+		}
+
+		/**
+		 * GTag Script looks like this:
+		 *
+		 * <script async src="https://www.googletagmanager.com/gtag/js?id=xxxxxx"></script>
+		 * <script>
+		 *   window.dataLayer = window.dataLayer || [];
+		 *   function gtag(){dataLayer.push(arguments);}
+		 *   gtag('js', new Date());
+		 *
+		 *   gtag('config', 'xxxxxx');
+		 * </script>
+		 */
+		$scripts = $this->dom->xpath->query( '//script[ ( @async and starts-with( @src, "https://www.googletagmanager.com/gtag/js" ) ) or contains( text(), "function gtag(" ) ]' );
+		if ( ! $scripts instanceof DOMNodeList || 0 === $scripts->length ) {
+			return;
+		}
+
+		foreach ( $scripts as $script ) {
+			ValidationExemption::mark_node_as_px_verified( $script );
+		}
+
+		/**
+		 * Mark inline gtag events as PX verified attributes.
+		 *
+		 * Such inline events can look like:
+		 *
+		 * onclick="gtag('event','click', { 'event_category':"click", 'event_label':"contactPage" })"
+		 * onsubmit="gtag('event','submit', { 'event_category':"submit", 'event_label':"contactPage" })"
+		 * onkeypress="gtag('event','keypress', { 'event_category':"keypress", 'event_label':"contactPage" })"
+		 */
+		$inline_events = $this->dom->xpath->query(
+			'
+				//@*[
+					starts-with(name(), "on")
+					and
+					name() != "on"
+					and
+					contains(., "gtag(")
+				]
+			'
+		);
+
+		if ( $inline_events instanceof DOMNodeList ) {
+			foreach ( $inline_events as $inline_event ) {
+				ValidationExemption::mark_node_as_px_verified( $inline_event );
+			}
+		}
+	}
+}

src/Option.php

@@ -208,6 +208,21 @@ interface Option {
 	 */
 	const SUPPRESSED_PLUGINS_USERNAME = 'username';
 
+
+	/**
+	 * Option key for enabling sandboxing.
+	 *
+	 * @var string
+	 */
+	const SANDBOXING_ENABLED = 'sandboxing_enabled';
+
+	/**
+	 * Option key for sandboxing level.
+	 *
+	 * @var string
+	 */
+	const SANDBOXING_LEVEL = 'sandboxing_level';
+
 	/**
 	 * Version of the AMP plugin for which the options were last saved.
 	 *

src/Sandboxing.php

@@ -14,6 +14,7 @@
 use AMP_Style_Sanitizer;
 use AmpProject\AmpWP\Infrastructure\Registerable;
 use AmpProject\AmpWP\Infrastructure\Service;
+use AmpProject\AmpWP\Option;
 use AmpProject\Dom\Document;
 use AmpProject\Dom\Element;
 use AmpProject\Html\Attribute;
@@ -32,14 +33,17 @@ final class Sandboxing implements Service, Registerable {
 	/**
 	 * Option key for enabling sandboxing.
 	 *
+	 * @deprecated Use Options interface for option keys.
+	 *
 	 * @var string
 	 */
 	const OPTION_ENABLED = 'sandboxing_enabled';
 
 	/**
 	 * Option key for sandboxing level.
 	 *
-	 * @todo Move this to the Options interface once no longer experimental.
+	 * @deprecated Use Options interface for option keys.
+	 *
 	 * @var string
 	 */
 	const OPTION_LEVEL = 'sandboxing_level';
@@ -57,11 +61,11 @@ final class Sandboxing implements Service, Registerable {
 	 * @var array
 	 */
 	const DEFAULT_OPTIONS_SCHEMA = [
-		self::OPTION_ENABLED => [
+		Option::SANDBOXING_ENABLED => [
 			'type'    => 'bool',
 			'default' => false,
 		],
-		self::OPTION_LEVEL   => [
+		Option::SANDBOXING_LEVEL   => [
 			'type'    => 'int',
 			'enum'    => self::LEVELS,
 			'default' => 1,
@@ -113,15 +117,15 @@ public function filter_default_options( $defaults ) {
 	 * @return array Sanitized options.
 	 */
 	public function sanitize_options( $options, $new_options ) {
-		if ( isset( $new_options[ self::OPTION_ENABLED ] ) ) {
-			$options[ self::OPTION_ENABLED ] = (bool) $new_options[ self::OPTION_ENABLED ];
+		if ( isset( $new_options[ Option::SANDBOXING_ENABLED ] ) ) {
+			$options[ Option::SANDBOXING_ENABLED ] = (bool) $new_options[ Option::SANDBOXING_ENABLED ];
 		}
 		if (
-			isset( $new_options[ self::OPTION_LEVEL ] )
+			isset( $new_options[ Option::SANDBOXING_LEVEL ] )
 			&&
-			in_array( $new_options[ self::OPTION_LEVEL ], self::LEVELS, true )
+			in_array( $new_options[ Option::SANDBOXING_LEVEL ], self::LEVELS, true )
 		) {
-			$options[ self::OPTION_LEVEL ] = $new_options[ self::OPTION_LEVEL ];
+			$options[ Option::SANDBOXING_LEVEL ] = $new_options[ Option::SANDBOXING_LEVEL ];
 		}
 		return $options;
 	}
@@ -137,11 +141,11 @@ public function add_hooks() {
 			return;
 		}
 
-		if ( ! AMP_Options_Manager::get_option( self::OPTION_ENABLED ) ) {
+		if ( ! AMP_Options_Manager::get_option( Option::SANDBOXING_ENABLED ) ) {
 			return;
 		}
 
-		$sandboxing_level = AMP_Options_Manager::get_option( self::OPTION_LEVEL );
+		$sandboxing_level = AMP_Options_Manager::get_option( Option::SANDBOXING_LEVEL );
 
 		// Opt-in to the new script sanitization logic in the script sanitizer.
 		add_filter(
@@ -241,7 +245,7 @@ private function remove_required_amp_markup_if_not_used( Document $dom, $effecti
 	 * @param int      $effective_sandboxing_level Effective sandboxing level.
 	 */
 	public function finalize_document( Document $dom, $effective_sandboxing_level ) {
-		$actual_sandboxing_level = AMP_Options_Manager::get_option( self::OPTION_LEVEL );
+		$actual_sandboxing_level = AMP_Options_Manager::get_option( Option::SANDBOXING_LEVEL );
 
 		$meta_generator = $dom->xpath->query( '/html/head/meta[ @name = "generator" and starts-with( @content, "AMP Plugin" ) ]/@content' )->item( 0 );
 		if ( $meta_generator instanceof DOMAttr ) {

tests/php/src/SandboxingTest.php

@@ -60,15 +60,15 @@ public function test_filter_rest_options_schema() {
 
 		$filtered = $this->instance->filter_rest_options_schema( $existing );
 		$this->assertArrayHasKey( 'foo', $filtered );
-		$this->assertArrayHasKey( Sandboxing::OPTION_LEVEL, $filtered );
+		$this->assertArrayHasKey( Option::SANDBOXING_LEVEL, $filtered );
 	}
 
 	/** @covers ::filter_default_options() */
 	public function test_filter_default_options() {
 		$this->assertEquals(
 			[
-				Sandboxing::OPTION_LEVEL   => 1,
-				Sandboxing::OPTION_ENABLED => false,
+				Option::SANDBOXING_LEVEL   => 1,
+				Option::SANDBOXING_ENABLED => false,
 			],
 			$this->instance->filter_default_options( [] )
 		);
@@ -77,34 +77,34 @@ public function test_filter_default_options() {
 	/** @covers ::sanitize_options() */
 	public function test_sanitize_options() {
 		$this->assertEquals(
-			[ Sandboxing::OPTION_LEVEL => 2 ],
+			[ Option::SANDBOXING_LEVEL => 2 ],
 			$this->instance->sanitize_options(
-				[ Sandboxing::OPTION_LEVEL => 2 ],
-				[ Sandboxing::OPTION_LEVEL => 'bad' ]
+				[ Option::SANDBOXING_LEVEL => 2 ],
+				[ Option::SANDBOXING_LEVEL => 'bad' ]
 			)
 		);
 
 		$this->assertEquals(
-			[ Sandboxing::OPTION_LEVEL => 3 ],
+			[ Option::SANDBOXING_LEVEL => 3 ],
 			$this->instance->sanitize_options(
-				[ Sandboxing::OPTION_LEVEL => 2 ],
-				[ Sandboxing::OPTION_LEVEL => 3 ]
+				[ Option::SANDBOXING_LEVEL => 2 ],
+				[ Option::SANDBOXING_LEVEL => 3 ]
 			)
 		);
 
 		$this->assertEquals(
-			[ Sandboxing::OPTION_LEVEL => 1 ],
+			[ Option::SANDBOXING_LEVEL => 1 ],
 			$this->instance->sanitize_options(
-				[ Sandboxing::OPTION_LEVEL => 1 ],
-				[ Sandboxing::OPTION_LEVEL => 0 ]
+				[ Option::SANDBOXING_LEVEL => 1 ],
+				[ Option::SANDBOXING_LEVEL => 0 ]
 			)
 		);
 
 		$this->assertEquals(
-			[ Sandboxing::OPTION_LEVEL => 1 ],
+			[ Option::SANDBOXING_LEVEL => 1 ],
 			$this->instance->sanitize_options(
-				[ Sandboxing::OPTION_LEVEL => 1 ],
-				[ Sandboxing::OPTION_LEVEL => 4 ]
+				[ Option::SANDBOXING_LEVEL => 1 ],
+				[ Option::SANDBOXING_LEVEL => 4 ]
 			)
 		);
 	}
@@ -114,9 +114,9 @@ public function test_add_hooks_not_standard_mode() {
 		$this->register_settings_and_set_user();
 		AMP_Options_Manager::update_options(
 			[
-				Sandboxing::OPTION_ENABLED => true,
+				Option::SANDBOXING_ENABLED => true,
 				Option::THEME_SUPPORT      => AMP_Theme_Support::TRANSITIONAL_MODE_SLUG,
-				Sandboxing::OPTION_LEVEL   => 2,
+				Option::SANDBOXING_LEVEL   => 2,
 			]
 		);
 		$this->instance->add_hooks();
@@ -128,7 +128,7 @@ public function test_add_hooks_without_enabled_level() {
 		$this->register_settings_and_set_user();
 		AMP_Options_Manager::update_options(
 			[
-				Sandboxing::OPTION_ENABLED => false,
+				Option::SANDBOXING_ENABLED => false,
 				Option::THEME_SUPPORT      => AMP_Theme_Support::STANDARD_MODE_SLUG,
 			]
 		);
@@ -178,9 +178,9 @@ public function test_add_hooks( $level, $expected_sanitizer_args ) {
 		$this->register_settings_and_set_user();
 		AMP_Options_Manager::update_options(
 			[
-				Sandboxing::OPTION_ENABLED => true,
+				Option::SANDBOXING_ENABLED => true,
 				Option::THEME_SUPPORT      => AMP_Theme_Support::STANDARD_MODE_SLUG,
-				Sandboxing::OPTION_LEVEL   => $level,
+				Option::SANDBOXING_LEVEL   => $level,
 			]
 		);
 		$this->instance->add_hooks();
@@ -250,8 +250,8 @@ public function test_finalize_document_and_get_effective_level( $min_level, $bod
 		$this->register_settings_and_set_user();
 		AMP_Options_Manager::update_options(
 			[
-				Sandboxing::OPTION_ENABLED => true,
-				Sandboxing::OPTION_LEVEL   => $min_level,
+				Option::SANDBOXING_ENABLED => true,
+				Option::SANDBOXING_LEVEL   => $min_level,
 			]
 		);