External Rewrite Rules

Here’s a quick (hopefully error-free!) example of adding an internal rewrite and loading a plugin file to process those requests. This will give you access to the WordPress environment so you can use the database, etc..

The general steps are:

1. add your rewrite and point it to index.php with your custom query vars appended
2. register your custom query vars so WordPress knows what they are
3. hook the parse_request action and check if one of the query vars is set. if it is, load the plugin file and exit before WordPress does the default query and loads the template

.

<?php
/*
Plugin Name: PLG
Plugin URI:
Description:
Author:
Version:
Author URI:
*/

class PLG {

    static $plugin_path;

    public function __construct(){
        $this->plugin_path = plugin_dir_path(__FILE__);
        register_activation_hook( __FILE__, array( $this, 'flush' ) );
        add_action( 'init', array( $this, 'init') );
        add_filter( 'query_vars', array( $this, 'query_vars') );
        add_action( 'parse_request', array( $this, 'parse_request') );
    }

    public function flush(){
        $this->init();
        flush_rewrite_rules();
    }

    public function init(){
        add_rewrite_rule(
            'plm_check/([a-zA-z0-9_]+)/([a-zA-z0-9-]+)/([0-9]+)/?$',
            'index.php?plmvar1=$matches[1]&plmvar2=$matches[2]&plmvar3=$matches[3]',
            'top'
        );
    }

    public function query_vars( $query_vars ){
        $query_vars[] = 'plmvar1';
        $query_vars[] = 'plmvar2';
        $query_vars[] = 'plmvar3';
        return $query_vars;
    }

    public function parse_request( &$wp ){
        if ( array_key_exists( 'plmvar1', $wp->query_vars ) ){
            include $this->plugin_path . 'webservices/plm_check.php';
            exit();
        }
        return;
    }

}
$wpa8185_plg = new PLG();

In your plugin file plm_check.php, you can access your query vars like:

<?php
global $wp;
echo $wp->query_vars['plmvar1'];