^^&&^^

Edit File: class-kkart-rest-crud-controller.php

<?php
/**
 * Abstract Rest CRUD Controller Class
 *
 * @class    KKART_REST_CRUD_Controller
 * @package Kkart\RestApi
 * @version  3.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * KKART_REST_CRUD_Controller class.
 *
 * @extends KKART_REST_Posts_Controller
 */
abstract class KKART_REST_CRUD_Controller extends KKART_REST_Posts_Controller {

/**
	 * Endpoint namespace.
	 *
	 * @var string
	 */
	protected $namespace = 'kkart/v2';

/**
	 * If object is hierarchical.
	 *
	 * @var bool
	 */
	protected $hierarchical = false;

/**
	 * Get object.
	 *
	 * @param  int $id Object ID.
	 * @return object KKART_Data object or WP_Error object.
	 */
	protected function get_object( $id ) {
		// translators: %s: Class method name.
		return new WP_Error( 'invalid-method', sprintf( __( "Method '%s' not implemented. Must be overridden in subclass.", 'kkart' ), __METHOD__ ), array( 'status' => 405 ) );
	}

/**
	 * Check if a given request has access to read an item.
	 *
	 * @param  WP_REST_Request $request Full details about the request.
	 * @return WP_Error|boolean
	 */
	public function get_item_permissions_check( $request ) {
		$object = $this->get_object( (int) $request['id'] );

if ( $object && 0 !== $object->get_id() && ! kkart_rest_check_post_permissions( $this->post_type, 'read', $object->get_id() ) ) {
			return new WP_Error( 'kkart_rest_cannot_view', __( 'Sorry, you cannot view this resource.', 'kkart' ), array( 'status' => rest_authorization_required_code() ) );
		}

return true;
	}

/**
	 * Check if a given request has access to update an item.
	 *
	 * @param  WP_REST_Request $request Full details about the request.
	 * @return WP_Error|boolean
	 */
	public function update_item_permissions_check( $request ) {
		$object = $this->get_object( (int) $request['id'] );

if ( $object && 0 !== $object->get_id() && ! kkart_rest_check_post_permissions( $this->post_type, 'edit', $object->get_id() ) ) {
			return new WP_Error( 'kkart_rest_cannot_edit', __( 'Sorry, you are not allowed to edit this resource.', 'kkart' ), array( 'status' => rest_authorization_required_code() ) );
		}

return true;
	}

/**
	 * Check if a given request has access to delete an item.
	 *
	 * @param  WP_REST_Request $request Full details about the request.
	 * @return bool|WP_Error
	 */
	public function delete_item_permissions_check( $request ) {
		$object = $this->get_object( (int) $request['id'] );

if ( $object && 0 !== $object->get_id() && ! kkart_rest_check_post_permissions( $this->post_type, 'delete', $object->get_id() ) ) {
			return new WP_Error( 'kkart_rest_cannot_delete', __( 'Sorry, you are not allowed to delete this resource.', 'kkart' ), array( 'status' => rest_authorization_required_code() ) );
		}

return true;
	}

/**
	 * Get object permalink.
	 *
	 * @param  object $object Object.
	 * @return string
	 */
	protected function get_permalink( $object ) {
		return '';
	}

/**
	 * Prepares the object for the REST response.
	 *
	 * @since  3.0.0
	 * @param  KKART_Data         $object  Object data.
	 * @param  WP_REST_Request $request Request object.
	 * @return WP_Error|WP_REST_Response Response object on success, or WP_Error object on failure.
	 */
	protected function prepare_object_for_response( $object, $request ) {
		// translators: %s: Class method name.
		return new WP_Error( 'invalid-method', sprintf( __( "Method '%s' not implemented. Must be overridden in subclass.", 'kkart' ), __METHOD__ ), array( 'status' => 405 ) );
	}

/**
	 * Prepares one object for create or update operation.
	 *
	 * @since  3.0.0
	 * @param  WP_REST_Request $request Request object.
	 * @param  bool            $creating If is creating a new object.
	 * @return WP_Error|KKART_Data The prepared item, or WP_Error object on failure.
	 */
	protected function prepare_object_for_database( $request, $creating = false ) {
		// translators: %s: Class method name.
		return new WP_Error( 'invalid-method', sprintf( __( "Method '%s' not implemented. Must be overridden in subclass.", 'kkart' ), __METHOD__ ), array( 'status' => 405 ) );
	}

/**
	 * Get a single item.
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_Error|WP_REST_Response
	 */
	public function get_item( $request ) {
		$object = $this->get_object( (int) $request['id'] );

if ( ! $object || 0 === $object->get_id() ) {
			return new WP_Error( "kkart_rest_{$this->post_type}_invalid_id", __( 'Invalid ID.', 'kkart' ), array( 'status' => 404 ) );
		}

$data     = $this->prepare_object_for_response( $object, $request );
		$response = rest_ensure_response( $data );

if ( $this->public ) {
			$response->link_header( 'alternate', $this->get_permalink( $object ), array( 'type' => 'text/html' ) );
		}

return $response;
	}

/**
	 * Save an object data.
	 *
	 * @since  3.0.0
	 * @param  WP_REST_Request $request  Full details about the request.
	 * @param  bool            $creating If is creating a new object.
	 * @return KKART_Data|WP_Error
	 */
	protected function save_object( $request, $creating = false ) {
		try {
			$object = $this->prepare_object_for_database( $request, $creating );

if ( is_wp_error( $object ) ) {
				return $object;
			}

$object->save();

return $this->get_object( $object->get_id() );
		} catch ( KKART_Data_Exception $e ) {
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), $e->getErrorData() );
		} catch ( KKART_REST_Exception $e ) {
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), array( 'status' => $e->getCode() ) );
		}
	}

/**
	 * Create a single item.
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_Error|WP_REST_Response
	 */
	public function create_item( $request ) {
		if ( ! empty( $request['id'] ) ) {
			/* translators: %s: post type */
			return new WP_Error( "kkart_rest_{$this->post_type}_exists", sprintf( __( 'Cannot create existing %s.', 'kkart' ), $this->post_type ), array( 'status' => 400 ) );
		}

$object = $this->save_object( $request, true );

if ( is_wp_error( $object ) ) {
			return $object;
		}

try {
			$this->update_additional_fields_for_object( $object, $request );

/**
			 * Fires after a single object is created or updated via the REST API.
			 *
			 * @param KKART_Data         $object    Inserted object.
			 * @param WP_REST_Request $request   Request object.
			 * @param boolean         $creating  True when creating object, false when updating.
			 */
			do_action( "kkart_rest_insert_{$this->post_type}_object", $object, $request, true );
		} catch ( KKART_Data_Exception $e ) {
			$object->delete();
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), $e->getErrorData() );
		} catch ( KKART_REST_Exception $e ) {
			$object->delete();
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), array( 'status' => $e->getCode() ) );
		}

$request->set_param( 'context', 'edit' );
		$response = $this->prepare_object_for_response( $object, $request );
		$response = rest_ensure_response( $response );
		$response->set_status( 201 );
		$response->header( 'Location', rest_url( sprintf( '/%s/%s/%d', $this->namespace, $this->rest_base, $object->get_id() ) ) );

return $response;
	}

/**
	 * Update a single post.
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_Error|WP_REST_Response
	 */
	public function update_item( $request ) {
		$object = $this->get_object( (int) $request['id'] );

if ( ! $object || 0 === $object->get_id() ) {
			return new WP_Error( "kkart_rest_{$this->post_type}_invalid_id", __( 'Invalid ID.', 'kkart' ), array( 'status' => 400 ) );
		}

$object = $this->save_object( $request, false );

if ( is_wp_error( $object ) ) {
			return $object;
		}

try {
			$this->update_additional_fields_for_object( $object, $request );

/**
			 * Fires after a single object is created or updated via the REST API.
			 *
			 * @param KKART_Data         $object    Inserted object.
			 * @param WP_REST_Request $request   Request object.
			 * @param boolean         $creating  True when creating object, false when updating.
			 */
			do_action( "kkart_rest_insert_{$this->post_type}_object", $object, $request, false );
		} catch ( KKART_Data_Exception $e ) {
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), $e->getErrorData() );
		} catch ( KKART_REST_Exception $e ) {
			return new WP_Error( $e->getErrorCode(), $e->getMessage(), array( 'status' => $e->getCode() ) );
		}

$request->set_param( 'context', 'edit' );
		$response = $this->prepare_object_for_response( $object, $request );
		return rest_ensure_response( $response );
	}

/**
	 * Prepare objects query.
	 *
	 * @since  3.0.0
	 * @param  WP_REST_Request $request Full details about the request.
	 * @return array
	 */
	protected function prepare_objects_query( $request ) {
		$args                        = array();
		$args['offset']              = $request['offset'];
		$args['order']               = $request['order'];
		$args['orderby']             = $request['orderby'];
		$args['paged']               = $request['page'];
		$args['post__in']            = $request['include'];
		$args['post__not_in']        = $request['exclude'];
		$args['posts_per_page']      = $request['per_page'];
		$args['name']                = $request['slug'];
		$args['post_parent__in']     = $request['parent'];
		$args['post_parent__not_in'] = $request['parent_exclude'];
		$args['s']                   = $request['search'];

if ( 'date' === $args['orderby'] ) {
			$args['orderby'] = 'date ID';
		}

$args['date_query'] = array();
		// Set before into date query. Date query must be specified as an array of an array.
		if ( isset( $request['before'] ) ) {
			$args['date_query'][0]['before'] = $request['before'];
		}

// Set after into date query. Date query must be specified as an array of an array.
		if ( isset( $request['after'] ) ) {
			$args['date_query'][0]['after'] = $request['after'];
		}

// Force the post_type argument, since it's not a user input variable.
		$args['post_type'] = $this->post_type;

/**
		 * Filter the query arguments for a request.
		 *
		 * Enables adding extra arguments or setting defaults for a post
		 * collection request.
		 *
		 * @param array           $args    Key value array of query var to query value.
		 * @param WP_REST_Request $request The request used.
		 */
		$args = apply_filters( "kkart_rest_{$this->post_type}_object_query", $args, $request );

return $this->prepare_items_query( $args, $request );
	}

/**
	 * Get objects.
	 *
	 * @since  3.0.0
	 * @param  array $query_args Query args.
	 * @return array
	 */
	protected function get_objects( $query_args ) {
		$query  = new WP_Query();
		$result = $query->query( $query_args );

$total_posts = $query->found_posts;
		if ( $total_posts < 1 ) {
			// Out-of-bounds, run the query again without LIMIT for total count.
			unset( $query_args['paged'] );
			$count_query = new WP_Query();
			$count_query->query( $query_args );
			$total_posts = $count_query->found_posts;
		}

return array(
			'objects' => array_filter( array_map( array( $this, 'get_object' ), $result ) ),
			'total'   => (int) $total_posts,
			'pages'   => (int) ceil( $total_posts / (int) $query->query_vars['posts_per_page'] ),
		);
	}

/**
	 * Get a collection of posts.
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_Error|WP_REST_Response
	 */
	public function get_items( $request ) {
		$query_args    = $this->prepare_objects_query( $request );
		$query_results = $this->get_objects( $query_args );

$objects = array();
		foreach ( $query_results['objects'] as $object ) {
			if ( ! kkart_rest_check_post_permissions( $this->post_type, 'read', $object->get_id() ) ) {
				continue;
			}

$data = $this->prepare_object_for_response( $object, $request );
			$objects[] = $this->prepare_response_for_collection( $data );
		}

$page      = (int) $query_args['paged'];
		$max_pages = $query_results['pages'];

$response = rest_ensure_response( $objects );
		$response->header( 'X-WP-Total', $query_results['total'] );
		$response->header( 'X-WP-TotalPages', (int) $max_pages );

$base          = $this->rest_base;
		$attrib_prefix = '(?P<';
		if ( strpos( $base, $attrib_prefix ) !== false ) {
			$attrib_names = array();
			preg_match( '/$\?P<[^>]+>.*$/', $base, $attrib_names, PREG_OFFSET_CAPTURE );
			foreach ( $attrib_names as $attrib_name_match ) {
				$beginning_offset = strlen( $attrib_prefix );
				$attrib_name_end  = strpos( $attrib_name_match[0], '>', $attrib_name_match[1] );
				$attrib_name      = substr( $attrib_name_match[0], $beginning_offset, $attrib_name_end - $beginning_offset );
				if ( isset( $request[ $attrib_name ] ) ) {
					$base  = str_replace( "(?P<$attrib_name>[\d]+)", $request[ $attrib_name ], $base );
				}
			}
		}
		$base = add_query_arg( $request->get_query_params(), rest_url( sprintf( '/%s/%s', $this->namespace, $base ) ) );

if ( $page > 1 ) {
			$prev_page = $page - 1;
			if ( $prev_page > $max_pages ) {
				$prev_page = $max_pages;
			}
			$prev_link = add_query_arg( 'page', $prev_page, $base );
			$response->link_header( 'prev', $prev_link );
		}
		if ( $max_pages > $page ) {
			$next_page = $page + 1;
			$next_link = add_query_arg( 'page', $next_page, $base );
			$response->link_header( 'next', $next_link );
		}

return $response;
	}

/**
	 * Delete a single item.
	 *
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_REST_Response|WP_Error
	 */
	public function delete_item( $request ) {
		$force  = (bool) $request['force'];
		$object = $this->get_object( (int) $request['id'] );
		$result = false;

if ( ! $object || 0 === $object->get_id() ) {
			return new WP_Error( "kkart_rest_{$this->post_type}_invalid_id", __( 'Invalid ID.', 'kkart' ), array( 'status' => 404 ) );
		}

$supports_trash = EMPTY_TRASH_DAYS > 0 && is_callable( array( $object, 'get_status' ) );

/**
		 * Filter whether an object is trashable.
		 *
		 * Return false to disable trash support for the object.
		 *
		 * @param boolean $supports_trash Whether the object type support trashing.
		 * @param KKART_Data $object         The object being considered for trashing support.
		 */
		$supports_trash = apply_filters( "kkart_rest_{$this->post_type}_object_trashable", $supports_trash, $object );

if ( ! kkart_rest_check_post_permissions( $this->post_type, 'delete', $object->get_id() ) ) {
			/* translators: %s: post type */
			return new WP_Error( "kkart_rest_user_cannot_delete_{$this->post_type}", sprintf( __( 'Sorry, you are not allowed to delete %s.', 'kkart' ), $this->post_type ), array( 'status' => rest_authorization_required_code() ) );
		}

$request->set_param( 'context', 'edit' );
		$response = $this->prepare_object_for_response( $object, $request );

// If we're forcing, then delete permanently.
		if ( $force ) {
			$object->delete( true );
			$result = 0 === $object->get_id();
		} else {
			// If we don't support trashing for this type, error out.
			if ( ! $supports_trash ) {
				/* translators: %s: post type */
				return new WP_Error( 'kkart_rest_trash_not_supported', sprintf( __( 'The %s does not support trashing.', 'kkart' ), $this->post_type ), array( 'status' => 501 ) );
			}

// Otherwise, only trash if we haven't already.
			if ( is_callable( array( $object, 'get_status' ) ) ) {
				if ( 'trash' === $object->get_status() ) {
					/* translators: %s: post type */
					return new WP_Error( 'kkart_rest_already_trashed', sprintf( __( 'The %s has already been deleted.', 'kkart' ), $this->post_type ), array( 'status' => 410 ) );
				}

$object->delete();
				$result = 'trash' === $object->get_status();
			}
		}

if ( ! $result ) {
			/* translators: %s: post type */
			return new WP_Error( 'kkart_rest_cannot_delete', sprintf( __( 'The %s cannot be deleted.', 'kkart' ), $this->post_type ), array( 'status' => 500 ) );
		}

/**
		 * Fires after a single object is deleted or trashed via the REST API.
		 *
		 * @param KKART_Data          $object   The deleted or trashed object.
		 * @param WP_REST_Response $response The response data.
		 * @param WP_REST_Request  $request  The request sent to the API.
		 */
		do_action( "kkart_rest_delete_{$this->post_type}_object", $object, $response, $request );

return $response;
	}

/**
	 * Prepare links for the request.
	 *
	 * @param KKART_Data         $object  Object data.
	 * @param WP_REST_Request $request Request object.
	 * @return array                   Links for the given post.
	 */
	protected function prepare_links( $object, $request ) {
		$links = array(
			'self' => array(
				'href' => rest_url( sprintf( '/%s/%s/%d', $this->namespace, $this->rest_base, $object->get_id() ) ),
			),
			'collection' => array(
				'href' => rest_url( sprintf( '/%s/%s', $this->namespace, $this->rest_base ) ),
			),
		);

return $links;
	}

/**
	 * Get the query params for collections of attachments.
	 *
	 * @return array
	 */
	public function get_collection_params() {
		$params                       = array();
		$params['context']            = $this->get_context_param();
		$params['context']['default'] = 'view';

$params['page'] = array(
			'description'        => __( 'Current page of the collection.', 'kkart' ),
			'type'               => 'integer',
			'default'            => 1,
			'sanitize_callback'  => 'absint',
			'validate_callback'  => 'rest_validate_request_arg',
			'minimum'            => 1,
		);
		$params['per_page'] = array(
			'description'        => __( 'Maximum number of items to be returned in result set.', 'kkart' ),
			'type'               => 'integer',
			'default'            => 10,
			'minimum'            => 1,
			'maximum'            => 100,
			'sanitize_callback'  => 'absint',
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['search'] = array(
			'description'        => __( 'Limit results to those matching a string.', 'kkart' ),
			'type'               => 'string',
			'sanitize_callback'  => 'sanitize_text_field',
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['after'] = array(
			'description'        => __( 'Limit response to resources published after a given ISO8601 compliant date.', 'kkart' ),
			'type'               => 'string',
			'format'             => 'date-time',
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['before'] = array(
			'description'        => __( 'Limit response to resources published before a given ISO8601 compliant date.', 'kkart' ),
			'type'               => 'string',
			'format'             => 'date-time',
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['exclude'] = array(
			'description'       => __( 'Ensure result set excludes specific IDs.', 'kkart' ),
			'type'              => 'array',
			'items'             => array(
				'type'          => 'integer',
			),
			'default'           => array(),
			'sanitize_callback' => 'wp_parse_id_list',
		);
		$params['include'] = array(
			'description'       => __( 'Limit result set to specific ids.', 'kkart' ),
			'type'              => 'array',
			'items'             => array(
				'type'          => 'integer',
			),
			'default'           => array(),
			'sanitize_callback' => 'wp_parse_id_list',
		);
		$params['offset'] = array(
			'description'        => __( 'Offset the result set by a specific number of items.', 'kkart' ),
			'type'               => 'integer',
			'sanitize_callback'  => 'absint',
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['order'] = array(
			'description'        => __( 'Order sort attribute ascending or descending.', 'kkart' ),
			'type'               => 'string',
			'default'            => 'desc',
			'enum'               => array( 'asc', 'desc' ),
			'validate_callback'  => 'rest_validate_request_arg',
		);
		$params['orderby'] = array(
			'description'        => __( 'Sort collection by object attribute.', 'kkart' ),
			'type'               => 'string',
			'default'            => 'date',
			'enum'               => array(
				'date',
				'id',
				'include',
				'title',
				'slug',
				'modified',
			),
			'validate_callback'  => 'rest_validate_request_arg',
		);

if ( $this->hierarchical ) {
			$params['parent'] = array(
				'description'       => __( 'Limit result set to those of particular parent IDs.', 'kkart' ),
				'type'              => 'array',
				'items'             => array(
					'type'          => 'integer',
				),
				'sanitize_callback' => 'wp_parse_id_list',
				'default'           => array(),
			);
			$params['parent_exclude'] = array(
				'description'       => __( 'Limit result set to all items except those of a particular parent ID.', 'kkart' ),
				'type'              => 'array',
				'items'             => array(
					'type'          => 'integer',
				),
				'sanitize_callback' => 'wp_parse_id_list',
				'default'           => array(),
			);
		}

/**
		 * Filter collection parameters for the posts controller.
		 *
		 * The dynamic part of the filter `$this->post_type` refers to the post
		 * type slug for the controller.
		 *
		 * This filter registers the collection parameter, but does not map the
		 * collection parameter to an internal WP_Query parameter. Use the
		 * `rest_{$this->post_type}_query` filter to set WP_Query parameters.
		 *
		 * @param array        $query_params JSON Schema-formatted collection parameters.
		 * @param WP_Post_Type $post_type    Post type object.
		 */
		return apply_filters( "rest_{$this->post_type}_collection_params", $params, $this->post_type );
	}
}