How do I create a 'route' in wordpress?

Question

For my own sanity I'm trying to create a route for an ajax api that looks something like:

/api/<action>

I'd like wordpress to handle this route and delegate to the proper action with do_action. Does wordpress give me a hook to implement this? Where's a good spot?

Answer 1

You have to use add_rewrite_rule

Something like:

add_action('init', 'theme_functionality_urls');

function theme_functionality_urls() {

  /* Order section by fb likes */
  add_rewrite_rule(
    '^tus-fotos/mas-votadas/page/(\d)?',
    'index.php?post_type=usercontent&orderby=fb_likes&paged=$matches[1]',
    'top'
  );
  add_rewrite_rule(
    '^tus-fotos/mas-votadas?',
    'index.php?post_type=usercontent&orderby=fb_likes',
    'top'
  );

}

This creates /tus-fotos/mas-votadas and /tus-fotos/mas-votadas/page/{number}, that changes the orderby query var for a custom one, which I handle in the pre_get_posts filter.

New variables can also be added using the query_vars filters and adding it to the rewrite rule.

add_filter('query_vars', 'custom_query_vars');
add_action('init', 'theme_functionality_urls');

function custom_query_vars($vars){
  $vars[] = 'api_action';
  return $vars;
}

function theme_functionality_urls() {

  add_rewrite_rule(
    '^api/(\w)?',
    'index.php?api_action=$matches[1]',
    'top'
  );

}

Then, handle the custom request:

add_action('parse_request', 'custom_requests');
function custom_requests ( $wp ) { 

  $valid_actions = array('action1', 'action2');

  if(
    !empty($wp->query_vars['api_action']) &&
    in_array($wp->query_vars['api_action'], $valid_actions) 
  ) {

    // do something here

  }

}

Just remember to flush the rewrite rules by visiting /wp-admin/options-permalink.php or calling flush_rewrite_rules only when needed, since it's not a trivial process.