How do I create an AJAX callback to Drupal video link?
You need a route and callback defined in a hook_menu. Below is a kickstarter not a complete example ;)

function example_module_menu() {
  $items = array();

  // an endpoint to add an entity to the default flag_list
  $items['node/%/play'] = array(
    'page callback' =&gt; 'example_module_video_count',
    'page arguments' =&gt; array(1),
    'access callback' =&gt; 'user_access',
    'access arguments' =&gt; array('access content'),
    'type' =&gt; MENU_CALLBACK,
    'delivery callback' =&gt; 'ajax_deliver',
  );
  return $items;
}


Here is the callback

function example_module_video_count($nid = NULL) {
    /* do you stuff */
    $node = node_load($nid);
    $commands = array();
    /* add some ajax commands if required, look at ajax_command_invoke */
    return array('#type' =&gt; 'ajax', '#commands' =&gt; $commands);    
}


Hit the URL from jQuery.ajax()

$.post("/node/1/play", function(data) {});