Building a custom REST API
Building a REST api via the ASP_Query class
The WordPress built in REST API supports extension via the register_rest_route function. We can use that to build a custom REST interface to access the search results.
In the following examples the ASP_Query class is used in the REST API handler functions.

Simple search example

In this example a simple search is executed by sending the "s" and "id" arguments to the /wp-json/ajax-search-pro/v0/search endpoint via a POST request.
/**
Sample payload query arguments:
array(
's' => 'test',
'id' => 1
)
*/
function asp_custom_rest_handler( $data ) {
$defaults = $args = array(
's' => '',
'id' => -1
);
foreach ( $defaults as $k => $v ) {
$param = $data->get_param($k);
if ( $param !== null ) {
$args[$k] = $param;
}
}
$asp_query = new ASP_Query($args, $args['id']);
return $asp_query->posts;
}
// POST to: http://example.com/wp-json/ajax-search-pro/v0/search
add_action( 'rest_api_init', function () {
register_rest_route('ajax-search-pro/v0', '/search', array(
'methods' => 'POST',
'callback' => 'asp_custom_rest_handler',
));
});

Sample request

curl --location -g --request POST 'http://test.local/wp-json/ajax-search-pro/v0/search?s=test&id=1
$response = wp_safe_remote_post(
'http://test.local/wp-json/ajax-search-pro/v0/search',
array(
'body' => array(
's' => 'test',
'id' => 1
)
)
);
var_dump($response['body']);

Search with post taxonomy filters

In this example a simple search is executed by sending the "s" and "id" as well as "post_tax_filter" arguments to the /wp-json/ajax-search-pro/v0/search endpoint via a POST request.
/**
Sample payload query arguments:
array(
's' => 'test',
'id' => 1,
'post_tax_filter' => array(
'category' => array(1, 2),
'post_tag' => array(3)
)
)
*/
function asp_custom_rest_handler( $data ) {
$defaults = $args = array(
's' => '',
'id' => -1
);
$params = $data->get_params();
foreach ( $defaults as $k => $v ) {
if ( isset($params[$k]) && $params[$k] !== null ) {
$args[$k] = $params[$k];
}
}
// Post taxonomy filter
if ( isset($params['post_tax_filter']) ) {
$args['post_tax_filter'] = array();
foreach ( $params['post_tax_filter'] as $taxonomy => $terms ) {
if ( taxonomy_exists($taxonomy) && is_array($terms) && count($terms) ) {
$args['post_tax_filter'][] = array(
'taxonomy' => $taxonomy,
'include' => array_map('intval', $terms),
'allow_empty' => false
);
}
}
}
$asp_query = new ASP_Query($args, $args['id']);
return $asp_query->posts;
}
// POST to: http://example.com/wp-json/ajax-search-pro/v2/id/1/search
add_action( 'rest_api_init', function () {
register_rest_route('ajax-search-pro/v0', '/search', array(
'methods' => 'POST',
'callback' => 'asp_custom_rest_handler',
));
});

Sample request

curl --location -g --request POST 'http://test.local/wp-json/ajax-search-pro/v0/search?s=test&id=1&post_tax_filter[category][]=1&post_tax_filter[category][]=2&post_tax_filter[post_tag][]=3'
$response = wp_safe_remote_post(
'http://test.local/wp-json/ajax-search-pro/v0/search',
array(
'body' => array(
's' => 'test',
'id' => 1,
'post_tax_filter' => array(
'category' => array(1, 2),
'post_tag' => array(3)
)
)
)
);
var_dump($response['body']);