Add Advanced Custom Fields Fields to the WP REST API

functions.php

function wp_api_encode_acf($data,$post,$context){
	$data['meta'] = array_merge($data['meta'],get_fields($post['ID']));
	return $data;
}

if( function_exists('get_fields') ){
	add_filter('json_prepare_post', 'wp_api_encode_acf', 10, 3);
}

I use the following when using v2 of https://github.com/WP-API/WP-API

function wp_rest_api_alter() {
  register_api_field( 'post',
      'fields',
      array(
        'get_callback'    => function($data, $field, $request, $type){
          if (function_exists('get_fields')) {
            return get_fields($data['id']);
          }
          return [];
        },
        'update_callback' => null,
        'schema'          => null,
      )
  );
}
add_action( 'rest_api_init', 'wp_rest_api_alter');

@davidmaneuver Thank you so much !

This is working with REST API v2 for me: https://github.com/airesvsg/acf-to-rest-api

I have created a custom post type and it has meta too. the custom post name is before_after and it is using multi post thumbnail library two metas are before_image and after_image, how i can add these two metas to REST API using the following code:

    function wp_api_encode_acf($data,$post,$context){

    $field_name = "after_image";
$data['mymeta'] = get_post_meta( $object[ 'id' ], $field_name );

return $data;
    }
    add_filter('json_prepare_post', 'wp_api_encode_acf', 10, 3);

Thank you!

The given solution didn't work for me on WordPress 5.2 but this works.

/**
 * Create REST field of ACF values for WordPress REST API
 */
function create_acf_fields_key_for_rest_api() {
	register_rest_field(
		[ 'post', 'page' ], // add post types here
		'acf_fields', // name of the field
		array(
			'get_callback'    => 'get_acf_fields_for_api',
			'update_callback' => null,
			'schema'          => null,
		)
	);
}
add_action( 'rest_api_init', 'create_acf_fields_key_for_rest_api' );

/**
 * Get ACF fields of the current post for the REST API field
 *
 * @param array $object post object array
 * @return array acf fields related to current post
 */
function get_acf_fields_for_api( $object ) {
	$data = get_fields( get_the_ID() );
	return $data ?: false;
}

@mehmoodak: Thank you :)

I am trying to send a post to my post type and it gives me an error, I am using custom field, help please, thank you

@albertoavv The REST route you are giving isn't correct. I didn't work with ACF REST API so please read their docs carefully. By the way I also thinks that in your path wp/wp5/wp-json should be changed to wp/wp-json

Thank you for your response, if what happens is that w5 is the name of the project or the root, but thanks for your response I will continue looking for a solution,

Regards

@mehmoodak thnx for your solution. Do you have any suggestion to specify only which ACF fields do you want to retrieve or not ?

great contribution @rileypaulsen! thanks. it works

Thanks @mehmoodak !

Thank you so much @mehmoodak !