return detailed errors from the fonts api

lib/experimental/fonts/font-library/class-wp-font-family.php

@@ -240,7 +240,7 @@ private function download_asset( $url, $filename ) {
 	}
 
 	/**
-	 * Moves an uploaded font face asset from temp folder to the fonts directory.
+	 * Moves an uploaded font face asset from temp directory to the fonts directory.
 	 *
 	 * This is used when uploading local fonts.
 	 *
@@ -266,10 +266,14 @@ private function move_font_face_asset( $font_face, $file ) {
 		// If the filename has no font mime type, don't move the file and
 		// return the font face definition without src to be ignored later.
 		if ( ! WP_Font_Family_Utils::has_font_mime_type( $filename ) ) {
-			return $new_font_face;
+			$error = new WP_Error(
+				'font_mime_check_failed',
+				__( 'The font mime type is not valid.', 'gutenberg' )
+			);
+			return array( $new_font_face, $error );
 		}
 
-		// Move the uploaded font asset from the temp folder to the fonts directory.
+		// Move the uploaded font asset from the temp directory to the fonts directory.
 		if ( ! function_exists( 'wp_handle_upload' ) ) {
 			require_once ABSPATH . 'wp-admin/includes/file.php';
 		}
@@ -284,7 +288,12 @@ private function move_font_face_asset( $font_face, $file ) {
 			$new_font_face['src'] = $handled_file['url'];
 		}
 
-		return $new_font_face;
+		$error = isset( $handled_file['error'] ) ? new WP_Error(
+			'font_face_upload_failed',
+			__( 'The font face assets could not be uploaded.', 'gutenberg' )
+		) : null;
+
+		return array( $new_font_face, $error );
 	}
 
 	/**
@@ -333,6 +342,7 @@ private function download_font_face_assets( $font_face ) {
 		$sources              = (array) $font_face['downloadFromUrl'];
 		$new_font_face['src'] = array();
 		$index                = 0;
+		$has_errors           = false;
 
 		foreach ( $sources as $src ) {
 			$suffix   = $index++ > 0 ? $index : '';
@@ -345,6 +355,8 @@ private function download_font_face_assets( $font_face ) {
 			$new_src  = $this->download_asset( $src, $filename );
 			if ( $new_src ) {
 				$new_font_face['src'][] = $new_src;
+			} else {
+				$has_errors = true;
 			}
 		}
 
@@ -356,7 +368,12 @@ private function download_font_face_assets( $font_face ) {
 		// because it is no longer needed.
 		unset( $new_font_face['downloadFromUrl'] );
 
-		return $new_font_face;
+		$error = $has_errors ? new WP_Error(
+			'font_face_download_failed',
+			__( 'The font face assets could not be downloaded.', 'gutenberg' )
+		) : null;
+
+		return array( $new_font_face, $error );
 	}
 
 
@@ -370,13 +387,14 @@ private function download_font_face_assets( $font_face ) {
 	 * @return bool True if the font faces were downloaded or moved successfully, false otherwise.
 	 */
 	private function download_or_move_font_faces( $files ) {
+		$errors = array();
 		if ( ! $this->has_font_faces() ) {
-			return true;
+			return array( true, $errors );
 		}
 
 		$new_font_faces = array();
 		foreach ( $this->data['fontFace'] as $font_face ) {
-			// If the fonts are not meant to be dowloaded or uploaded
+			// If the fonts are not meant to be downloaded or uploaded
 			// (for example to install fonts that use a remote url).
 			$new_font_face = $font_face;
 
@@ -396,18 +414,22 @@ private function download_or_move_font_faces( $files ) {
 
 			// If installing google fonts, download the font face assets.
 			if ( ! empty( $font_face['downloadFromUrl'] ) ) {
-				$new_font_face = $this->download_font_face_assets( $new_font_face );
+				list( $new_font_face, $error ) = $this->download_font_face_assets( $new_font_face );
 			}
 
 			// If installing local fonts, move the font face assets from
-			// the temp folder to the wp fonts directory.
+			// the temp directory to the wp fonts directory.
 			if ( ! empty( $font_face['uploadedFile'] ) && ! empty( $files ) ) {
-				$new_font_face = $this->move_font_face_asset(
+				list( $new_font_face, $error ) = $this->move_font_face_asset(
 					$new_font_face,
 					$files[ $new_font_face['uploadedFile'] ]
 				);
 			}
 
+			if ( is_wp_error( $error ) ) {
+				$errors[] = $error;
+			}
+
 			/*
 			 * If the font face assets were successfully downloaded, add the font face
 			 * to the new font. Font faces with failed downloads are not added to the
@@ -420,10 +442,10 @@ private function download_or_move_font_faces( $files ) {
 
 		if ( ! empty( $new_font_faces ) ) {
 			$this->data['fontFace'] = $new_font_faces;
-			return true;
+			return array( true, $errors );
 		}
 
-		return false;
+		return array( false, $errors );
 	}
 
 	/**
@@ -597,17 +619,21 @@ private function create_or_update_font_post() {
 	public function install( $files = null ) {
 		add_filter( 'upload_mimes', array( 'WP_Font_Library', 'set_allowed_mime_types' ) );
 		add_filter( 'upload_dir', array( 'WP_Font_Library', 'set_upload_dir' ) );
-		$were_assets_written = $this->download_or_move_font_faces( $files );
+		list($were_assets_written, $errors) = $this->download_or_move_font_faces( $files );
 		remove_filter( 'upload_dir', array( 'WP_Font_Library', 'set_upload_dir' ) );
 		remove_filter( 'upload_mimes', array( 'WP_Font_Library', 'set_allowed_mime_types' ) );
 
 		if ( ! $were_assets_written ) {
-			return new WP_Error(
-				'font_face_download_failed',
+			$errors[] = new WP_Error(
+				'font_face_upload_failed',
 				__( 'The font face assets could not be written.', 'gutenberg' )
 			);
 		}
 
+		if ( ! empty( $errors ) ) {
+			return $errors;
+		}
+
 		$post_id = $this->create_or_update_font_post();
 
 		if ( is_wp_error( $post_id ) ) {

lib/experimental/fonts/font-library/class-wp-rest-font-library-controller.php

@@ -327,8 +327,8 @@ public function update_font_library_permissions_check() {
 		$upload_dir = wp_upload_dir()['basedir'];
 		if ( ! is_writable( $temp_dir ) || ! wp_is_writable( $upload_dir ) ) {
 			return new WP_Error(
-				'rest_cannot_write_fonts_folder',
-				__( 'Error: WordPress does not have permission to write the fonts folder on your server.', 'gutenberg' ),
+				'rest_cannot_write_fonts',
+				__( 'Error: WordPress does not have permission to write the fonts directory on your server.', 'gutenberg' ),
 				array(
 					'status' => 500,
 				)
@@ -375,8 +375,8 @@ public function install_fonts( $request ) {
 		// Iterates the fonts data received and creates a new WP_Font_Family object for each one.
 		$fonts_installed = array();
 		foreach ( $fonts_to_install as $font_data ) {
-			$font = new WP_Font_Family( $font_data );
-			$font->install( $files );
+			$font              = new WP_Font_Family( $font_data );
+			$errors            = $font->install( $files );
 			$fonts_installed[] = $font;
 		}
 
@@ -388,6 +388,14 @@ public function install_fonts( $request ) {
 			);
 		}
 
+		if ( ! empty( $errors ) ) {
+			return new WP_Error(
+				'error_installing_fonts',
+				__( 'Error installing fonts.', 'gutenberg' ),
+				array( 'status' => 500 )
+			);
+		}
+
 		$response = array();
 		foreach ( $fonts_installed as $font ) {
 			$response[] = $font->get_data();