WP API V2: Query posts by ACF

Question

I would like to query my posts by filtering for a custom meta added with Advanced Custom Fields. It's a boolean meta, so every post will have something like:

GET http://localhost/wp-json/wp/v2/posts

{
  ...
  "acf" : {
    "highlight" : true
  }
  ...
}

I'm not able to filter by this meta value, even if I exposed meta_key and meta_value to the REST API in function.php:

function my_add_meta_vars ($current_vars) {
    $current_vars = array_merge ($current_vars, array ('meta_key', 'meta_value'));
    return $current_vars;
}
add_filter ('rest_query_vars', 'my_add_meta_vars');

But if I try:

GET http://localhost/wp-json/wp/v2/posts?filter[meta_key]=highlight&filter[meta_value]=true

I see all the posts as if the filter is ignored.

The filter parameter was disabled when the REST API was merged into WP Core. You can add it back with the rest-filter plugin. Here's the article: developer.wordpress.org/rest-api/using-the-rest-api/… And here's the link to the filter plugin: github.com/wp-api/rest-filter — codescribblr

LucaP LucaP · Accepted Answer · 2018-01-22T09:51:02

I was able to get this solved with this customization:

add_filter( 'rest_query_vars', function ( $valid_vars ) {
    return array_merge( $valid_vars, array( 'highlight', 'meta_query' ) );
} );
add_filter( 'rest_post_query', function( $args, $request ) {
    $highlight   = $request->get_param( 'highlight' );

    if ( ! empty( $highlight ) ) {
        $args['meta_query'] = array(
            array(
                'key'     => 'highlight',
                'value'   => $highlight,
                'compare' => '=',
            )
        );      
    }

    return $args;
}, 10, 2 );

And do a query in this way (highlight is acf boolean)

GET /wp-json/wp/v2/posts?highlight=1

WP API V2: Query posts by ACF

1 Answers