Add debugging query arguments

includes/class-amp-theme-support.php

@@ -95,6 +95,27 @@ class AMP_Theme_Support {
 	 */
 	const READER_MODE_TEMPLATE_DIRECTORY = 'amp';
 
+	/**
+	 * A query var to disable post processing.
+	 *
+	 * @var string
+	 */
+	const DISABLE_POST_PROCESSING_QUERY_VAR = 'disable_post_processing';
+
+	/**
+	 * A query var to disable the response cache.
+	 *
+	 * @var string
+	 */
+	const DISABLE_RESPONSE_CACHE_QUERY_VAR = 'disable_response_cache';
+
+	/**
+	 * A query var to prevent a redirect to a non-AMP URL.
+	 *
+	 * @var string
+	 */
+	const PREVENT_REDIRECT_TO_NON_AMP_QUERY_VAR = 'prevent_redirect';
+
 	/**
 	 * Sanitizer classes.
 	 *
@@ -1872,6 +1893,10 @@ public static function start_output_buffering() {
 			newrelic_disable_autorum();
 		}
 
+		if ( isset( $_GET[ self::DISABLE_POST_PROCESSING_QUERY_VAR ] ) && AMP_Validation_Manager::has_cap() ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+			return;
+		}
+
 		ob_start( [ __CLASS__, 'finish_output_buffering' ] );
 		self::$is_output_buffering = true;
 	}
@@ -2000,13 +2025,17 @@ public static function prepare_response( $response, $args = [] ) {
 		 *
 		 * @param bool $enable_response_caching Whether response caching is enabled.
 		 */
-		$enable_response_caching = apply_filters( 'amp_response_caching_enabled', ! ( defined( 'WP_DEBUG' ) && WP_DEBUG ) || ! empty( $args['enable_response_caching'] ) );
+		$enable_response_caching    = apply_filters( 'amp_response_caching_enabled', ! ( defined( 'WP_DEBUG' ) && WP_DEBUG ) || ! empty( $args['enable_response_caching'] ) );
+		$is_disabled_with_query_var = isset( $_GET[ self::DISABLE_RESPONSE_CACHE_QUERY_VAR ] ) && AMP_Validation_Manager::has_cap(); // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+
 		$enable_response_caching = (
 			$enable_response_caching
 			&&
 			! AMP_Validation_Manager::should_validate_response()
 			&&
 			! is_customize_preview()
+			&&
+			! $is_disabled_with_query_var
 		);
 
 		// When response caching is enabled, determine if it should be turned off for cache misses.
@@ -2121,7 +2150,15 @@ public static function prepare_response( $response, $args = [] ) {
 				AMP_HTTP::send_server_timing( 'amp_processor_cache_hit', -$prepare_response_start );
 
 				// Redirect to non-AMP version.
-				if ( ! amp_is_canonical() && ! is_singular( AMP_Story_Post_Type::POST_TYPE_SLUG ) && $blocking_error_count > 0 ) {
+				if (
+					! amp_is_canonical()
+					&&
+					! is_singular( AMP_Story_Post_Type::POST_TYPE_SLUG )
+					&&
+					$blocking_error_count > 0
+					&&
+					! self::prevent_redirect_to_non_amp()
+				) {
 					if ( AMP_Validation_Manager::has_cap() ) {
 						$non_amp_url = add_query_arg( AMP_Validation_Manager::VALIDATION_ERRORS_QUERY_VAR, $blocking_error_count, $non_amp_url );
 					}
@@ -2266,7 +2303,7 @@ public static function prepare_response( $response, $args = [] ) {
 					$script->appendChild( $dom->createTextNode( 'document.addEventListener( "DOMContentLoaded", function() { document.write = function( text ) { throw new Error( "[AMP-WP] Prevented document.write() call with: "  + text ); }; } );' ) );
 					$head->appendChild( $script );
 				}
-			} elseif ( ! self::is_customize_preview_iframe() ) {
+			} elseif ( ! self::is_customize_preview_iframe() && ! self::prevent_redirect_to_non_amp() ) {
 				$response = esc_html__( 'Redirecting to non-AMP version.', 'amp' );
 
 				if ( $cache_response ) {
@@ -2278,6 +2315,15 @@ public static function prepare_response( $response, $args = [] ) {
 					$non_amp_url = add_query_arg( AMP_Validation_Manager::VALIDATION_ERRORS_QUERY_VAR, $blocking_error_count, $non_amp_url );
 				}
 
+				// Remove debugging query args.
+				$non_amp_url = remove_query_arg(
+					[
+						self::DISABLE_RESPONSE_CACHE_QUERY_VAR,
+						AMP_Validation_Error_Taxonomy::REJECT_ALL_VALIDATION_ERRORS_QUERY_VAR,
+					],
+					$non_amp_url
+				);
+
 				/*
 				 * Temporary redirect because AMP page may return with blocking validation errors when auto-accepting sanitization
 				 * is not enabled. A 302 will allow the errors to be fixed without needing to bust any redirect caches.
@@ -2313,6 +2359,19 @@ public static function prepare_response( $response, $args = [] ) {
 		return $response;
 	}
 
+	/**
+	 * Whether to prevent a redirect to a non-AMP URL.
+	 *
+	 * Usually, if there are unaccepted validation errors,
+	 * the AMP URL will redirect to a non-AMP URL.
+	 * This overrides that behavior, for debugging purposes.
+	 *
+	 * @return bool Whether the prevent a redirect.
+	 */
+	public static function prevent_redirect_to_non_amp() {
+		return isset( $_GET[ self::PREVENT_REDIRECT_TO_NON_AMP_QUERY_VAR ] ) && AMP_Validation_Manager::has_cap(); // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+	}
+
 	/**
 	 * Check for cache misses. When found, store in an option to retain the URL.
 	 *

includes/validation/class-amp-validation-error-taxonomy.php

@@ -110,6 +110,13 @@ class AMP_Validation_Error_Taxonomy {
 	 */
 	const VALIDATION_ERRORS_CLEARED_QUERY_VAR = 'amp_validation_errors_cleared';
 
+	/**
+	 * Query var to reject all validation errors.
+	 *
+	 * @var string
+	 */
+	const REJECT_ALL_VALIDATION_ERRORS_QUERY_VAR = 'reject_all_errors';
+
 	/**
 	 * The <option> value to not filter at all, like for 'All Statuses'.
 	 *
@@ -465,6 +472,11 @@ public static function get_validation_error_sanitization( $error ) {
 			$forced = 'with_preview';
 		}
 
+		if ( isset( $_GET[ self::REJECT_ALL_VALIDATION_ERRORS_QUERY_VAR ] ) && AMP_Validation_Manager::has_cap() ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+			$status = self::VALIDATION_ERROR_ACK_REJECTED_STATUS;
+			$forced = 'with_query_var';
+		}
+
 		/**
 		 * Filters whether the validation error should be sanitized.
 		 *

includes/validation/class-amp-validation-manager.php

@@ -185,7 +185,7 @@ public static function init( $args = [] ) {
 			$args
 		);
 
-		self::$should_locate_sources = $args['should_locate_sources'];
+		self::$should_locate_sources = $args['should_locate_sources'] && ! AMP_Theme_Support::prevent_redirect_to_non_amp();
 
 		AMP_Validated_URL_Post_Type::register();
 		AMP_Validation_Error_Taxonomy::register();

tests/php/test-class-amp-theme-support.php

@@ -58,7 +58,8 @@ public function tearDown() {
 		AMP_Validation_Manager::reset_validation_results();
 		remove_theme_support( AMP_Theme_Support::SLUG );
 		remove_theme_support( 'custom-header' );
-		$_REQUEST                = []; // phpcs:ignore WordPress.CSRF.NonceVerification.NoNonceVerification
+		$_REQUEST                = [];
+		$_GET                    = [];
 		$_SERVER['QUERY_STRING'] = '';
 		unset( $_SERVER['REQUEST_URI'] );
 		unset( $_SERVER['REQUEST_METHOD'] );
@@ -1444,6 +1445,13 @@ function newrelic_disable_autorum() {
 		$this->assertEquals( $initial_ob_level + 1, ob_get_level() );
 		ob_end_flush();
 		$this->assertEquals( $initial_ob_level, ob_get_level() );
+
+		// When this query var is present, this method should exit early, and shouldn't buffer the output.
+		$_GET[ AMP_Theme_Support::DISABLE_POST_PROCESSING_QUERY_VAR ] = '';
+		wp_set_current_user( self::factory()->user->create( [ 'role' => 'administrator' ] ) );
+		$initial_ob_level = ob_get_level();
+		AMP_Theme_Support::start_output_buffering();
+		$this->assertEquals( $initial_ob_level, ob_get_level() );
 	}
 
 	/**
@@ -1730,7 +1738,14 @@ static function ( $url ) {
 		$last_server_timing_header = array_pop( $server_timing_headers );
 		$this->assertStringStartsWith( 'amp_processor_cache_hit;', $last_server_timing_header['value'] );
 		$this->assertCount( count( $server_timing_headers ), $initial_server_timing_headers );
+		$this->reset_post_processor_cache_effectiveness();
 
+		// Test that the response is not cached if a certain query var is present.
+		$_GET[ AMP_Theme_Support::DISABLE_RESPONSE_CACHE_QUERY_VAR ] = '';
+		wp_set_current_user( self::factory()->user->create( [ 'role' => 'administrator' ] ) );
+		$call_prepare_response();
+		$server_timing_headers = $this->get_server_timing_headers();
+		$this->assertCount( count( $server_timing_headers ), $this->get_server_timing_headers() );
 		// phpcs:enable WordPress.WP.EnqueuedResources.NonEnqueuedScript, WordPress.WP.EnqueuedResources.NonEnqueuedStylesheet
 	}
 
@@ -2090,6 +2105,24 @@ static function( $url ) use ( &$redirects ) {
 
 	}
 
+	/**
+	 * Test prevent_redirect_to_non_amp
+	 *
+	 * @covers AMP_Theme_Support::prevent_redirect_to_non_amp()
+	 */
+	public function test_prevent_redirect_to_non_amp() {
+		// The query var isn't present, and the user doesn't have the right permission.
+		$this->assertFalse( AMP_Theme_Support::prevent_redirect_to_non_amp() );
+
+		// The query var is present, but the user doesn't have the right permission.
+		$_GET[ AMP_Theme_Support::PREVENT_REDIRECT_TO_NON_AMP_QUERY_VAR ] = '';
+		$this->assertFalse( AMP_Theme_Support::prevent_redirect_to_non_amp() );
+
+		// Now that the user has the right permission, this should be true.
+		wp_set_current_user( self::factory()->user->create( [ 'role' => 'administrator' ] ) );
+		$this->assertTrue( AMP_Theme_Support::prevent_redirect_to_non_amp() );
+	}
+
 	/**
 	 * Test enqueue_assets().
 	 *

tests/php/validation/test-class-amp-validation-error-taxonomy.php

@@ -31,6 +31,7 @@ class Test_AMP_Validation_Error_Taxonomy extends WP_UnitTestCase {
 	 */
 	public function tearDown() {
 		$_REQUEST = [];
+		$_GET     = [];
 		remove_theme_support( AMP_Theme_Support::SLUG );
 		AMP_Theme_Support::read_theme_support();
 		remove_filter( 'amp_validation_error_sanitized', '__return_true' );
@@ -369,6 +370,19 @@ public function test_is_validation_error_sanitized_and_get_validation_error_sani
 			],
 			AMP_Validation_Error_Taxonomy::get_validation_error_sanitization( $error_bar )
 		);
+
+		// New rejected => Ack rejected, as the query var should force this to be rejected.
+		$_GET[ AMP_Validation_Error_Taxonomy::REJECT_ALL_VALIDATION_ERRORS_QUERY_VAR ] = '';
+		wp_set_current_user( self::factory()->user->create( [ 'role' => 'administrator' ] ) );
+		$this->assertfalse( AMP_Validation_Error_Taxonomy::is_validation_error_sanitized( $error_foo ) );
+		$this->assertEquals(
+			[
+				'forced'      => 'with_query_var',
+				'status'      => AMP_Validation_Error_Taxonomy::VALIDATION_ERROR_ACK_REJECTED_STATUS,
+				'term_status' => AMP_Validation_Error_Taxonomy::VALIDATION_ERROR_ACK_REJECTED_STATUS,
+			],
+			AMP_Validation_Error_Taxonomy::get_validation_error_sanitization( $error_foo )
+		);
 	}
 
 	/**