JSON API to show Advanced Custom Fields - WordPress - json

Question

I am developing a magazine WordPress site that will have a json feed for a Mobile App. I set the backend up using Advanced Custom Fields with a Repeater Field for Multiple Articles and Multiple Pages within each article. http://www.advancedcustomfields.com/add-ons/repeater-field/
I am using the JSON API but this does not include any of my custom fields. Is there currently a plugin that can do this?

Answer 1

#Myke: you helped me tremendously. Here's my humble addition:
add_filter('json_api_encode', 'json_api_encode_acf');
function json_api_encode_acf($response)
{
if (isset($response['posts'])) {
foreach ($response['posts'] as $post) {
json_api_add_acf($post); // Add specs to each post
}
}
else if (isset($response['post'])) {
json_api_add_acf($response['post']); // Add a specs property
}
return $response;
}
function json_api_add_acf(&$post)
{
$post->acf = get_fields($post->id);
}

Answer 2

Update for Wordpress 4.7
With the release of Wordpress 4.7 the REST functionality is no longer provided as a distinct plugin, rather its rolled in (no plugin required).
The previous filters don't appear to work. However the following snippet does (can be in your functions.php):
>= PHP 5.3
add_filter('rest_prepare_post', function($response) {
$response->data['acf'] = get_fields($response->data['id']);
return $response;
});
< PHP 5.3
add_filter('rest_prepare_post', 'append_acf');
function append_acf($response) {
$response->data['acf'] = get_fields($response->data['id']);
return $response;
};
Note the filter is a wild card filter, applied like
apply_filters("rest_prepare_$type", ...
so if you have multiple content types (custom), you will need to do:
add_filter('rest_prepare_multiple_choice', 'append_acf');
add_filter('rest_prepare_vocabularies', 'append_acf');
function append_acf($response) {
$response->data['acf'] = get_fields($response->data['id']);
return $response;
};
Note It appears that rest_prepare_x is called per record. So if you are pinging the index endpoint, it will be called multiple times (so you don't need to check if its posts or post)

Answer 3

Came here by searching with the same question. This isn't totally vetted yet but I think this is getting on the right path. Check it out.
I have one less nested level than you do so this might need altered a bit. But the JSON API plugin has a filter called json_api_encode. I have a repeater called specifications that looks like this.
http://d.pr/i/YMvv
In my functions file I have this.
add_filter('json_api_encode', 'my_encode_specs');
function my_encode_specs($response) {
if (isset($response['posts'])) {
foreach ($response['posts'] as $post) {
my_add_specs($post); // Add specs to each post
}
} else if (isset($response['post'])) {
my_add_specs($response['post']); // Add a specs property
}
return $response;
}
function my_add_specs(&$post) {
$post->specs = get_field('specifications', $post->id);
}
Which appends a custom value to the JSON API output. Notice the get_field function from ACF works perfectly here for bringing back the array of the repeater values.
Hope this helps!

Answer 4

There is now a small plugin which adds the filter for you.
https://github.com/PanManAms/WP-JSON-API-ACF

Answer 5

I'm not sure if you're still interested in a solution, but I was able to modify the json-api plugin models/post.php file to display the repeater data as an array. This is a modification of a modification made by http://wordpress-problem.com/marioario-on-plugin-json-api-fixed-get-all-custom-fields-the-right-way/
replace the set_custom_fields_value() function with the following:
function set_custom_fields_value() {
global $json_api;
if ($json_api->include_value('custom_fields') && $json_api->query->custom_fields) {
// Query string params for this query var
$params = trim($json_api->query->custom_fields);
// Get all custom fields if true|all|* is passed
if ($params === "*" || $params === "true" || $params === "all") {
$wp_custom_fields = get_post_custom($this->id);
$this->custom_fields = new stdClass();
// Loop through our custom fields and place on property
foreach($wp_custom_fields as $key => $val) {
if (get_field($key)) {
$this->custom_fields->$key = get_field($key);
} else if ($val) {
// Some fields are stored as serialized arrays.
// This method does not support multidimensionals...
// but didn't see anything wrong with this approach
$current_custom_field = #unserialize($wp_custom_fields[$key][0]);
if (is_array($current_custom_field)) {
// Loop through the unserialized array
foreach($current_custom_field as $sub_key => $sub_val) {
// Lets append these for correct JSON output
$this->custom_fields->$key->$sub_key = $sub_val;
}
} else {
// Break this value of this custom field out of its array
// and place it on the stack like usual
$this->custom_fields->$key = $wp_custom_fields[$key][0];
}
}
}
} else {
// Well this is the old way but with the unserialized array fix
$params = explode(',', $params);
$wp_custom_fields = get_post_custom($this->id);
$this->custom_fields = new stdClass();
foreach ($params as $key) {
if (isset($wp_custom_fields[$key]) && $wp_custom_fields[$key][0] ) {
$current_custom_field = #unserialize($wp_custom_fields[$key][0]);
if (is_array($current_custom_field)) {
foreach($current_custom_field as $sub_key => $sub_val) {
$this->custom_fields->$key->$sub_key = $sub_val;
}
} else {
$this->custom_fields->$key = $wp_custom_fields[$key][0];
}
}
}
}
} else {
unset($this->custom_fields);
}
}

Answer 6

Current version of ACF prints out a custom_fields object on a call to the JSON API, containing all the fields relative to the Post or Page. I edited #Myke version to add specific custom fields from the ACF Option page to each Post or Page. Unfortunately there is not get_fields() function for the whole Option Page so you'll have to edit it depending on your fields structure.
add_filter('json_api_encode', 'json_api_encode_acf');
function json_api_encode_acf($response) {
if (isset($response['posts'])) {
foreach ($response['posts'] as $post) {
json_api_add_acf($post); // Add specs to each post
}
}
else if (isset($response['post'])) {
json_api_add_acf($response['post']); // Add a specs property
}
else if (isset($response['page'])) {
json_api_add_acf($response['page']); // Add a specs to a page
}
return $response;
}
function json_api_add_acf(&$post) {
$post->custom_fields->NAME_OF_YOUR_CUSTOM_FIELD = get_field( 'NAME_OF_YOUR_CUSTOM_FIELD', 'option' );
}