From f5dde31290667669e4625a86d163cc8c2e76912d Mon Sep 17 00:00:00 2001
From: Timothy Jacobs <timothyblynjacobs@git.wordpress.org>
Date: Sun, 7 Jun 2020 22:40:16 +0000
Subject: [PATCH] REST API: Support the (min|max)Items JSON Schema keywords.

A future commit will add support for the uniqueItems keyword.

Props sorenbronsted.
See #48821.


git-svn-id: https://develop.svn.wordpress.org/trunk@47923 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/rest-api.php                  | 11 ++++++
 .../endpoints/class-wp-rest-controller.php    |  2 ++
 .../tests/rest-api/rest-controller.php        |  4 +++
 .../tests/rest-api/rest-schema-validation.php | 36 +++++++++++++++++++
 .../tests/rest-api/rest-test-controller.php   |  8 +++--
 5 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/src/wp-includes/rest-api.php b/src/wp-includes/rest-api.php
index e408522ab6..dc55af08f3 100644
--- a/src/wp-includes/rest-api.php
+++ b/src/wp-includes/rest-api.php
@@ -1250,6 +1250,7 @@ function rest_get_avatar_sizes() {
  * @since 5.5.0 Add the "uuid" and "hex-color" formats.
  *              Support the "minLength", "maxLength" and "pattern" keywords for strings.
  *              Validate required properties.
+ *              Support the "minItems" and "maxItems" keywords for arrays.
  *
  * @param mixed  $value The value to validate.
  * @param array  $args  Schema array to use for validation.
@@ -1287,6 +1288,16 @@ function rest_validate_value_from_schema( $value, $args, $param = '' ) {
 				return $is_valid;
 			}
 		}
+
+		if ( isset( $args['minItems'] ) && count( $value ) < $args['minItems'] ) {
+			/* translators: 1: Parameter, 2: number. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must contain at least %2$s items.' ), $param, number_format_i18n( $args['minItems'] ) ) );
+		}
+
+		if ( isset( $args['maxItems'] ) && count( $value ) > $args['maxItems'] ) {
+			/* translators: 1: Parameter, 2: number. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must contain at most %2$s items.' ), $param, number_format_i18n( $args['maxItems'] ) ) );
+		}
 	}
 
 	if ( 'object' === $args['type'] ) {
diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-controller.php
index a2d1134f11..0d1e85cbf1 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-controller.php
@@ -643,6 +643,8 @@ abstract class WP_REST_Controller {
 			'minLength',
 			'maxLength',
 			'pattern',
+			'minItems',
+			'maxItems',
 		);
 
 		foreach ( $schema_properties as $field_id => $params ) {
diff --git a/tests/phpunit/tests/rest-api/rest-controller.php b/tests/phpunit/tests/rest-api/rest-controller.php
index 887cb8f76e..b04158b037 100644
--- a/tests/phpunit/tests/rest-api/rest-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-controller.php
@@ -265,6 +265,10 @@ class WP_Test_REST_Controller extends WP_Test_REST_TestCase {
 
 		$this->assertArrayHasKey( 'items', $args['somearray'] );
 
+		foreach ( array( 'minItems', 'maxItems' ) as $property ) {
+			$this->assertArrayHasKey( $property, $args['somearray'] );
+		}
+
 		foreach ( array( 'properties', 'additionalProperties' ) as $property ) {
 			$this->assertArrayHasKey( $property, $args['someobject'] );
 		}
diff --git a/tests/phpunit/tests/rest-api/rest-schema-validation.php b/tests/phpunit/tests/rest-api/rest-schema-validation.php
index 09dd271a23..44a627e715 100644
--- a/tests/phpunit/tests/rest-api/rest-schema-validation.php
+++ b/tests/phpunit/tests/rest-api/rest-schema-validation.php
@@ -766,4 +766,40 @@ class WP_Test_REST_Schema_Validation extends WP_UnitTestCase {
 		$this->assertTrue( rest_validate_value_from_schema( 'â', $schema ) );
 		$this->assertWPError( rest_validate_value_from_schema( 'ââ', $schema ) );
 	}
+
+	/**
+	 * @ticket 48821
+	 */
+	public function test_array_min_items() {
+		$schema = array(
+			'type'     => 'array',
+			'minItems' => 1,
+			'items'    => array(
+				'type' => 'number',
+			),
+		);
+
+		$this->assertTrue( rest_validate_value_from_schema( array( 1, 2 ), $schema ) );
+		$this->assertTrue( rest_validate_value_from_schema( array( 1 ), $schema ) );
+		$this->assertWPError( rest_validate_value_from_schema( array(), $schema ) );
+		$this->assertWPError( rest_validate_value_from_schema( '', $schema ) );
+	}
+
+	/**
+	 * @ticket 48821
+	 */
+	public function test_array_max_items() {
+		$schema = array(
+			'type'     => 'array',
+			'maxItems' => 2,
+			'items'    => array(
+				'type' => 'number',
+			),
+		);
+
+		$this->assertTrue( rest_validate_value_from_schema( array( 1 ), $schema ) );
+		$this->assertTrue( rest_validate_value_from_schema( array( 1, 2 ), $schema ) );
+		$this->assertWPError( rest_validate_value_from_schema( array( 1, 2, 3 ), $schema ) );
+		$this->assertWPError( rest_validate_value_from_schema( 'foobar', $schema ) );
+	}
 }
diff --git a/tests/phpunit/tests/rest-api/rest-test-controller.php b/tests/phpunit/tests/rest-api/rest-test-controller.php
index a201ec1c80..e3a82586bc 100644
--- a/tests/phpunit/tests/rest-api/rest-test-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-test-controller.php
@@ -101,11 +101,13 @@ class WP_REST_Test_Controller extends WP_REST_Controller {
 					'default' => 'a',
 				),
 				'somearray'      => array(
-					'type'    => 'array',
-					'items'   => array(
+					'type'     => 'array',
+					'items'    => array(
 						'type' => 'string',
 					),
-					'context' => array( 'view' ),
+					'minItems' => 1,
+					'maxItems' => 10,
+					'context'  => array( 'view' ),
 				),
 				'someobject'     => array(
 					'type'                 => 'object',