WordPress - REST Request?

functions.php

/** 
 * is_rest_request
 * 
 * this method attempts to determine if the current request is for the REST API or not
 * based on a fiew factors
 * 
 * @since 7.4
 * @access public
 * @author Kevin Pirnie <[email protected]>
 * @package Protect Your REmote
 * 
 * @return bool This method returns a boolean value
 * 
*/
public static function is_rest_request( ) : bool {

	// hold our return, default as false
	$_ret = false;

	// our full requested URI
	$_uri = ( isset( $_SERVER['HTTPS'] ) && $_SERVER['HTTPS'] === 'on' ? "https" : "http" ) . "://" . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];

	// check if the REST_REQUEST constant is defined, and see if there is a rest_route attached to it
	if( defined( 'REST_REQUEST' ) && REST_REQUEST || isset( $_GET['rest_route'] ) && strpos( $_GET['rest_route'] , '/', 0 ) === 0 ) {

		// there is, return true
		$ret = true;

	}
		
	// check the wp_rewrite global
	global $wp_rewrite;

	// if it's not currently set
	if( ! $wp_rewrite ) {
		
		// set it
		$wp_rewrite = new WP_Rewrite( );
		
	}

	// parse the rest URL, if it exists
	$_rest_url = wp_parse_url( trailingslashit( rest_url( ) ) );

	// parse the current URL, if it exists
	$_current_url = wp_parse_url( $_uri );

	// the current ur path
	$_current_url_path = ( $_current_url['path'] ) ?? null;

	// check if the rest url matches the current url
	if( in_array( $_current_url_path, $_rest_url ) ) {

		// it does not, return true
		$_ret = true;

	}
	
	// get the rest prefix, if it exists
	$_rest_prefix = rest_get_url_prefix( );

	// set the return if the prefix matches
	$_ret = false !== strpos( $_uri, $_rest_prefix );

	// return our return
	return $_ret;

}