From eea69421645ad91c22f2ffbeace83b50a38056d3 Mon Sep 17 00:00:00 2001
From: danielbachhuber <danielbachhuber@git.wordpress.org>
Date: Mon, 29 Oct 2018 00:25:38 +0000
Subject: [PATCH] Block Editor: Preload `wp/v2/media` with OPTIONS for caps
 check.

Also introduces a `block_editor_preload_paths` filter for plugins and themes to preload additional data.

Props imath, mattheu.
Fixes #45194.

Built from https://develop.svn.wordpress.org/branches/5.0@43833


git-svn-id: http://core.svn.wordpress.org/branches/5.0@43662 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-admin/edit-form-blocks.php | 13 +++++++++++++
 wp-includes/rest-api.php      | 29 ++++++++++++++++++++++++-----
 wp-includes/version.php       |  2 +-
 3 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/wp-admin/edit-form-blocks.php b/wp-admin/edit-form-blocks.php
index d998a11dad..b3deab00d9 100644
--- a/wp-admin/edit-form-blocks.php
+++ b/wp-admin/edit-form-blocks.php
@@ -49,8 +49,21 @@ $preload_paths = array(
 	sprintf( '/wp/v2/%s/%s?context=edit', $rest_base, $post->ID ),
 	sprintf( '/wp/v2/types/%s?context=edit', $post_type ),
 	sprintf( '/wp/v2/users/me?post_type=%s&context=edit', $post_type ),
+	array( '/wp/v2/media', 'OPTIONS' ),
 );
 
+/**
+ * Preload common data by specifying an array of REST API paths that will be preloaded.
+ *
+ * Filters the array of paths that will be preloaded.
+ *
+ * @since 5.0.0
+ *
+ * @param array  $preload_paths Array of paths to preload.
+ * @param object $post          The post resource data.
+ */
+$preload_paths = apply_filters( 'block_editor_preload_paths', $preload_paths, $post );
+
 /*
  * Ensure the global $post remains the same after API data is preloaded.
  * Because API preloading can call the_content and other filters, plugins
diff --git a/wp-includes/rest-api.php b/wp-includes/rest-api.php
index e1d8919c8d..f1892c10c4 100644
--- a/wp-includes/rest-api.php
+++ b/wp-includes/rest-api.php
@@ -1343,12 +1343,22 @@ function rest_preload_api_request( $memo, $path ) {
 		return $memo;
 	}
 
+	$method = 'GET';
+	if ( is_array( $path ) && 2 === count( $path ) ) {
+		$method = end( $path );
+		$path   = reset( $path );
+
+		if ( ! in_array( $method, array( 'GET', 'OPTIONS' ), true ) ) {
+			$method = 'GET';
+		}
+	}
+
 	$path_parts = parse_url( $path );
 	if ( false === $path_parts ) {
 		return $memo;
 	}
 
-	$request = new WP_REST_Request( 'GET', $path_parts['path'] );
+	$request = new WP_REST_Request( $method, $path_parts['path'] );
 	if ( ! empty( $path_parts['query'] ) ) {
 		parse_str( $path_parts['query'], $query_params );
 		$request->set_query_params( $query_params );
@@ -1367,10 +1377,19 @@ function rest_preload_api_request( $memo, $path ) {
 			$data['_links'] = $links;
 		}
 
-		$memo[ $path ] = array(
-			'body'    => $data,
-			'headers' => $response->headers,
-		);
+		if ( 'OPTIONS' === $method ) {
+			$response = rest_send_allow_header( $response, $server, $request );
+
+			$memo[ $method ][ $path ] = array(
+				'body'    => $data,
+				'headers' => $response->headers,
+			);
+		} else {
+			$memo[ $path ] = array(
+				'body'    => $data,
+				'headers' => $response->headers,
+			);
+		}
 	}
 
 	return $memo;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index c00a71bbdf..954e91aceb 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-beta1-43832';
+$wp_version = '5.0-beta1-43833';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.