Unset data from WordPress API (wp-json) - php

Question

I can already unset (remove specifics from normal posts) in the json returned from the WordPress API. I actually use the following below from this example: https://css-tricks.com/using-the-wp-api-to-fetch-posts/
What I am having trouble with and can't figure out, is how to change this so it unsets data from a Custom Post Type
Thoughts?
function qod_remove_extra_data( $data, $post, $context ) {
// We only want to modify the 'view' context, for reading posts
if ( $context !== 'view' || is_wp_error( $data ) ) {
return $data;
}
// Here, we unset any data we don't want to see on the front end:
unset( $data['author'] );
unset( $data['status'] );
unset( $data['featured_image'] );
//etc etc
return $data;
}
add_filter( 'json_prepare_post', 'qod_remove_extra_data', 12, 3 );
custom post type example filter:
function projectPost_remove_extra_data( $data, $post, $context ) {
if ( $context !== 'view' || is_wp_error( $data ) ) {
return $data;
}
// Here, we unset any data we don't want to see on the front end:
unset( $data['author'] );
return $data;
}
add_filter( 'json_prepare_project', 'projectPost_remove_extra_data', 12, 3 );

Answer 1

For wp-api v1.x, you need to extend WP_JSON_CustomPostType. There is an example in the pages file (class-wp-json-pages.php)
<?php
/**
* Page post type handlers
*
* #package WordPress
* #subpackage JSON API
*/
/**
* Page post type handlers
*
* This class serves as a small addition on top of the basic post handlers to
* add small functionality on top of the existing API.
*
* In addition, this class serves as a sample implementation of building on top
* of the existing APIs for custom post types.
*
* #package WordPress
* #subpackage JSON API
*/
class WP_JSON_Pages extends WP_JSON_CustomPostType {
/**
* Base route
*
* #var string
*/
protected $base = '/pages';
/**
* Post type
*
* #var string
*/
protected $type = 'page';
/**
* Register the page-related routes
*
* #param array $routes Existing routes
* #return array Modified routes
*/
public function register_routes( $routes ) {
$routes = parent::register_routes( $routes );
$routes = parent::register_revision_routes( $routes );
$routes = parent::register_comment_routes( $routes );
// Add post-by-path routes
$routes[ $this->base . '/(?P<path>.+)'] = array(
array( array( $this, 'get_post_by_path' ), WP_JSON_Server::READABLE ),
array( array( $this, 'edit_post_by_path' ), WP_JSON_Server::EDITABLE | WP_JSON_Server::ACCEPT_JSON ),
array( array( $this, 'delete_post_by_path' ), WP_JSON_Server::DELETABLE ),
);
return $routes;
}
/**
* Retrieve a page by path name
*
* #param string $path
* #param string $context
*
* #return array|WP_Error
*/
public function get_post_by_path( $path, $context = 'view' ) {
$post = get_page_by_path( $path, ARRAY_A );
if ( empty( $post ) ) {
return new WP_Error( 'json_post_invalid_id', __( 'Invalid post ID.' ), array( 'status' => 404 ) );
}
return $this->get_post( $post['ID'], $context );
}
/**
* Edit a page by path name
*
* #param $path
* #param $data
* #param array $_headers
*
* #return true|WP_Error
*/
public function edit_post_by_path( $path, $data, $_headers = array() ) {
$post = get_page_by_path( $path, ARRAY_A );
if ( empty( $post ) ) {
return new WP_Error( 'json_post_invalid_id', __( 'Invalid post ID.' ), array( 'status' => 404 ) );
}
return $this->edit_post( $post['ID'], $data, $_headers );
}
/**
* Delete a page by path name
*
* #param $path
* #param bool $force
*
* #return true|WP_Error
*/
public function delete_post_by_path( $path, $force = false ) {
$post = get_page_by_path( $path, ARRAY_A );
if ( empty( $post ) ) {
return new WP_Error( 'json_post_invalid_id', __( 'Invalid post ID.' ), array( 'status' => 404 ) );
}
return $this->delete_post( $post['ID'], $force );
}
/**
* Prepare post data
*
* #param array $post The unprepared post data
* #param string $context The context for the prepared post. (view|view-revision|edit|embed|single-parent)
* #return array The prepared post data
*/
protected function prepare_post( $post, $context = 'view' ) {
$_post = parent::prepare_post( $post, $context );
// Override entity meta keys with the correct links
$_post['meta']['links']['self'] = json_url( $this->base . '/' . get_page_uri( $post['ID'] ) );
if ( ! empty( $post['post_parent'] ) ) {
$_post['meta']['links']['up'] = json_url( $this->base . '/' . get_page_uri( (int) $post['post_parent'] ) );
}
return apply_filters( 'json_prepare_page', $_post, $post, $context );
}
}
Replace "Pages" with "MyCustomPostTypes" and page with "mycustomposttype". Just be careful not to rename internal WordPress code that also uses the term page
Note: probably best to add this as a plugin rather than change the JSON-WP-API plugin
/**
* Plugin Name: MyCustom JSON App API
* Description: MyCustomPost handler for the JSON API
* Dependency: This plugin requires JSON-WP-API Plugin!!!!
* Author:
* Author URI:
* Version:
* Plugin URI:
*/

Answer 2

If possible, only the examples shown in internet is:
function qod_remove_extra_data ($ data, $ post, $ context) {
// We only want to modify the 'view' context, for reading posts
if ($ context! == 'view' || is_wp_error ($ data)) {
return $ data;
}
// Here, we unset any data we do not want to see on the front end:
unset ($data ['author']);
unset ($data ['status']);
// Continue unsetting whatever other fields you want return $ data;
}
add_filter ('json_prepare_post' 'qod remove extra_data', 12, 3);
and right is:
qod_remove_extra_data function ($ data, $ post, $ context) {
// We only want to modify the 'view' context, for reading posts
if ($ context! == 'view' || is_wp_error ($ data)) {
unset ( $data->data ['excerpt']); //Example
unset ($data->data ['content']); //Example
unset ($data->data ['name field to remove'])
//or
unset ($data->data ['name field to remove'] ['name subfield if you only want to delete the sub-field of field' ])
return $data;
}
}
add_filter ('rest_prepare_post' 'qod_remove_extra_data', 12, 3);
IMPORTANT:
Is:
add_filter ('rest_prepare_post' 'qod_remove_extra_data', 12, 3);
Not:
add_filter ('json_prepare_post' 'qod remove extra_data', 12, 3); //WRONG
If is Custom Post Type:
add_filter ('rest_prepare_{$post_type}' 'qod_remove_extra_data', 12, 3);
EXAMPLE: Name post type = product;
add_filter ('rest_prepare_product' 'qod_remove_extra_data', 12, 3);
With this code can remove the fields that you want the JSON. By using rest_prepare} _ {$ post_type decide that you eliminated every post_type fields, thus only affected the post_type you want and not all.

Answer 3

It should be no different to remove data from custom post types than from the built-in post types. Have you confirmed that your API call is actually returning your CPTs? First, you should look at the value of what is returned from: http://yourwebsite.com/wp-json/posts/types. Assuming that your CPT type shows up there, you should be able to query for items of that type, e.g. product, by calling: http://yourwebsite.com/wp-json/posts?type=product.
In other words, you should not change the name of the filter: you still want to tie into json_prepare_post. If you want to make your filter sensitive to post type and only remove certain fields if you have a CPT you could do something like:
function my_remove_extra_product_data( $data, $post, $context ) {
// make sure you've got the right custom post type
if ( 'product' !== $data[ 'type' ] ) {
return $data;
}
// now proceed as you saw in the other examples
if ( $context !== 'view' || is_wp_error( $data ) ) {
return $data;
}
// unset unwanted fields
unset( $data[ 'author' ] );
// finally, return the filtered data
return $data;
}
// make sure you use the SAME filter hook as for regular posts
add_filter( 'json_prepare_post', 'my_remove_extra_product_data', 12, 3 );
You can find more documentation in the WP API Getting Started Guide.