Block API: Preserve unknown, respect null in server attributes prep…

…aration (#12003) * Framework: Preserve unknown attributes in block render * Framework: Respect null as a valid attribute type * REST API: Update block renderer test to omit undefined defaults * REST API: Assign default for block renderer attributes Previously we would pass `NULL` to `render`. While `render` provides a default `array()` value, since an explicit value is provided, it would not take effect. With this change, the endpoint assures a default value to be provided as a parameter to get the `get_item` callback that is compatible with the function signature of `WP_BlockType::render`. Alternatively, it could be considered to have separate invocations of `render`, depending on whether the request parameter is set.
WordPress · Nov 20, 2018 · 53c975b · 53c975b
1 parent 9297fc9
commit 53c975b
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Showing 4 changed files with 48 additions and 17 deletions.
diff --git a/lib/class-wp-block-type.php b/lib/class-wp-block-type.php
@@ -120,36 +120,47 @@ public function is_dynamic() {
 
 	/**
 	 * Validates attributes against the current block schema, populating
-	 * defaulted and missing values, and omitting unknown attributes.
+	 * defaulted and missing values.
 	 *
 	 * @param  array $attributes Original block attributes.
 	 * @return array             Prepared block attributes.
 	 */
 	public function prepare_attributes_for_render( $attributes ) {
+		// If there are no attribute definitions for the block type, skip
+		// processing and return vebatim.
 		if ( ! isset( $this->attributes ) ) {
 			return $attributes;
 		}
 
-		$prepared_attributes = array();
+		foreach ( $attributes as $attribute_name => $value ) {
+			// If the attribute is not defined by the block type, it cannot be
+			// validated.
+			if ( ! isset( $this->attributes[ $attribute_name ] ) ) {
+				continue;
+			}
 
-		foreach ( $this->attributes as $attribute_name => $schema ) {
-			$value = null;
+			$schema = $this->attributes[ $attribute_name ];
 
-			if ( isset( $attributes[ $attribute_name ] ) ) {
-				$is_valid = rest_validate_value_from_schema( $attributes[ $attribute_name ], $schema );
-				if ( ! is_wp_error( $is_valid ) ) {
-					$value = rest_sanitize_value_from_schema( $attributes[ $attribute_name ], $schema );
-				}
+			// Validate value by JSON schema. An invalid value should revert to
+			// its default, if one exists. This occurs by virtue of the missing
+			// attributes loop immediately following. If there is not a default
+			// assigned, the attribute value should remain unset.
+			$is_valid = rest_validate_value_from_schema( $value, $schema );
+			if ( is_wp_error( $is_valid ) ) {
+				unset( $attributes[ $attribute_name ] );
 			}
+		}
 
-			if ( is_null( $value ) && isset( $schema['default'] ) ) {
-				$value = $schema['default'];
+		// Populate values of any missing attributes for which the block type
+		// defines a default.
+		$missing_schema_attributes = array_diff_key( $this->attributes, $attributes );
+		foreach ( $missing_schema_attributes as $attribute_name => $schema ) {
+			if ( isset( $schema['default'] ) ) {
+				$attributes[ $attribute_name ] = $schema['default'];
 			}
-
-			$prepared_attributes[ $attribute_name ] = $value;
 		}
 
-		return $prepared_attributes;
+		return $attributes;
 	}
 
 	/**

diff --git a/lib/class-wp-rest-block-renderer-controller.php b/lib/class-wp-rest-block-renderer-controller.php
@@ -59,6 +59,7 @@ public function register_routes() {
 								'type'                 => 'object',
 								'additionalProperties' => false,
 								'properties'           => $block_type->get_attributes(),
+								'default'              => array(),
 							),
 							'post_id'    => array(
 								'description' => __( 'ID of the post context.', 'gutenberg' ),

diff --git a/phpunit/class-block-type-test.php b/phpunit/class-block-type-test.php
@@ -139,7 +139,8 @@ function test_prepare_attributes() {
 			'wrongType'          => 5,
 			'wrongTypeDefaulted' => 5,
 			/* missingDefaulted */
-			'undefined'          => 'omit',
+			'undefined'          => 'include',
+			'intendedNull'       => null,
 		);
 
 		$block_type = new WP_Block_Type(
@@ -160,6 +161,10 @@ function test_prepare_attributes() {
 						'type'    => 'string',
 						'default' => 'define',
 					),
+					'intendedNull'       => array(
+						'type'    => array( 'string', 'null' ),
+						'default' => 'wrong',
+					),
 				),
 			)
 		);
@@ -169,14 +174,26 @@ function test_prepare_attributes() {
 		$this->assertEquals(
 			array(
 				'correct'            => 'include',
-				'wrongType'          => null,
+				/* wrongType */
 				'wrongTypeDefaulted' => 'defaulted',
 				'missingDefaulted'   => 'define',
+				'undefined'          => 'include',
+				'intendedNull'       => null,
 			),
 			$prepared_attributes
 		);
 	}
 
+	function test_prepare_attributes_none_defined() {
+		$attributes = array( 'exists' => 'keep' );
+
+		$block_type = new WP_Block_Type( 'core/dummy', array() );
+
+		$prepared_attributes = $block_type->prepare_attributes_for_render( $attributes );
+
+		$this->assertEquals( $attributes, $prepared_attributes );
+	}
+
 	function test_has_block_with_mixed_content() {
 		$mixed_post_content = 'before' .
 		'<!-- wp:core/dummy --><!-- /wp:core/dummy -->' .

diff --git a/phpunit/class-rest-block-renderer-controller-test.php b/phpunit/class-rest-block-renderer-controller-test.php
@@ -272,7 +272,9 @@ public function test_get_item_default_attributes() {
 		$block_type = WP_Block_Type_Registry::get_instance()->get_registered( self::$block_name );
 		$defaults   = array();
 		foreach ( $block_type->attributes as $key => $attribute ) {
-			$defaults[ $key ] = isset( $attribute['default'] ) ? $attribute['default'] : null;
+			if ( isset( $attribute['default'] ) ) {
+				$defaults[ $key ] = $attribute['default'];
+			}
 		}
 
 		$request = new WP_REST_Request( 'GET', self::$rest_api_route . self::$block_name );