From 1593f882256d6d835db9a0e73ec9d0128f297a8c Mon Sep 17 00:00:00 2001
From: Weston Ruter <weston@xwp.co>
Date: Fri, 2 Feb 2018 14:33:01 -0800
Subject: [PATCH] Remove support for handling non-redirecting post requests,
 for now

---
 includes/amp-helper-functions.php             | 31 ++--------------
 .../sanitizers/class-amp-form-sanitizer.php   | 37 ++++++-------------
 2 files changed, 16 insertions(+), 52 deletions(-)

diff --git a/includes/amp-helper-functions.php b/includes/amp-helper-functions.php
index bf25bd7ec4d..fc09db8580d 100644
--- a/includes/amp-helper-functions.php
+++ b/includes/amp-helper-functions.php
@@ -400,27 +400,18 @@ function amp_print_schemaorg_metadata() {
 }
 
 /**
- * Hook into a comment submission of an AMP XHR post request.
- *
- * This only runs on wp-comments-post.php.
+ * Hook into a form submissions, such as comment the form or some other .
  *
  * @since 0.7.0
+ * @global string $pagenow
  */
 function amp_handle_xhr_request() {
 	global $pagenow;
-	if ( isset( $_GET['__amp_redirect'] ) ) { // WPCS: CSRF ok.
-		add_action( 'template_redirect', function() {
-			// grab post data.
-			$transint_name = wp_unslash( $_GET['__amp_redirect'] ); // WPCS: CSRF ok, input var ok.
-			$_POST         = get_transient( $transint_name );
-			delete_transient( $transint_name );
-		}, 0 );
-	}
-	if ( ! isset( $_GET['__amp_source_origin'] ) || ! isset( $pagenow ) ) { // WPCS: CSRF ok. Beware of AMP_Theme_Support::purge_amp_query_vars().
+	if ( ! isset( $_GET['__amp_source_origin'] ) ) { // WPCS: CSRF ok. Beware of AMP_Theme_Support::purge_amp_query_vars().
 		return;
 	}
 
-	if ( 'wp-comments-post.php' === $pagenow ) {
+	if ( isset( $pagenow ) && 'wp-comments-post.php' === $pagenow ) {
 		// This only runs on wp-comments-post.php.
 		add_filter( 'comment_post_redirect', function() {
 			// We don't need any data, so just send a success.
@@ -428,21 +419,7 @@ function amp_handle_xhr_request() {
 		}, PHP_INT_MAX, 2 );
 		amp_handle_xhr_headers_output();
 	} elseif ( isset( $_GET['_wp_amp_action_xhr_converted'] ) ) { // WPCS: CSRF ok.
-		// Add amp redirect hooks.
 		add_filter( 'wp_redirect', 'amp_intercept_post_request_redirect', PHP_INT_MAX, 2 );
-		add_action( 'template_redirect', function() {
-			// grab post data.
-			$transient_name = uniqid();
-			set_transient( $transient_name, wp_unslash( $_POST ), 60 ); // WPCS: CSRF ok, input var ok.
-
-			/*
-			 * Buffering starts here, so unlikely the form has a redirect,
-			 * so force a redirect to the same page.
-			 */
-			$location = esc_url_raw( wp_unslash( $_SERVER['REQUEST_URI'] ) ); // WPCS: CSRF ok, input var ok.
-			$location = add_query_arg( '__amp_redirect', $transient_name, $location );
-			amp_intercept_post_request_redirect( $location );
-		}, 0 );
 		amp_handle_xhr_headers_output();
 	}
 
diff --git a/includes/sanitizers/class-amp-form-sanitizer.php b/includes/sanitizers/class-amp-form-sanitizer.php
index c3cdfe437b1..05c6252f0cc 100644
--- a/includes/sanitizers/class-amp-form-sanitizer.php
+++ b/includes/sanitizers/class-amp-form-sanitizer.php
@@ -91,7 +91,7 @@ public function sanitize() {
 					$action_url = add_query_arg( '_wp_amp_action_xhr_converted', 1, $action_url );
 					$node->setAttribute( 'action-xhr', $action_url );
 					// Append error handler if not found.
-					$this->error_handler( $node );
+					$this->ensure_submit_error_element( $node );
 				} elseif ( 'http://' === substr( $xhr_action, 0, 7 ) ) {
 					$node->setAttribute( 'action-xhr', substr( $xhr_action, 5 ) );
 				}
@@ -118,37 +118,24 @@ public function sanitize() {
 	 *
 	 * @link https://www.ampproject.org/docs/reference/components/amp-form#success/error-response-rendering
 	 * @since 0.7
-	 * @param DOMElement $node The form node to check.
+	 *
+	 * @param DOMElement $form The form node to check.
 	 */
-	public function error_handler( $node ) {
-		$templates = $node->getElementsByTagName( 'template' );
-		if ( $templates->length ) {
-			for ( $i = $templates->length - 1; $i >= 0; $i-- ) {
-				if ( $templates->item( $i )->parentNode->hasAttribute( 'submit-error' ) ) {
-					return; // Found error template, do nothing.
-				}
+	public function ensure_submit_error_element( $form ) {
+		$templates = $form->getElementsByTagName( 'template' );
+		for ( $i = $templates->length - 1; $i >= 0; $i-- ) {
+			if ( $templates->item( $i )->parentNode->hasAttribute( 'submit-error' ) ) {
+				return; // Found error template, do nothing.
 			}
 		}
-		$node->appendChild( $this->create_error_template() );
-	}
 
-	/**
-	 * Creates a error handler element node.
-	 *
-	 * @link https://www.ampproject.org/docs/reference/components/amp-form#success/error-response-rendering
-	 * @since 0.7
-	 *
-	 * @return DOMElement The div[submit-error] element.
-	 */
-	public function create_error_template() {
-		$node     = $this->dom->createElement( 'div' );
+		$div      = $this->dom->createElement( 'div' );
 		$template = $this->dom->createElement( 'template' );
 		$mustache = $this->dom->createTextNode( '{{{error}}}' );
-		$node->setAttribute( 'submit-error', '' );
+		$div->setAttribute( 'submit-error', '' );
 		$template->setAttribute( 'type', 'amp-mustache' );
 		$template->appendChild( $mustache );
-		$node->appendChild( $template );
-
-		return $node;
+		$div->appendChild( $template );
+		$form->appendChild( $div );
 	}
 }