[SOLVED] Server: find _id and update another collection?

Hi

I have some events _id’s and when people Approve a event I do this:

    Events.update(
      {_id: eventId},
      { $addToSet:{ approvedId: Meteor.userId() }}

    );  

To add the user to the approvelist

But howto on the main.js (server) make a:

var getthecat = Events.find(_id: eventId)

AND

Meteor.users.update(
          {_id: Meteor.userId()},
          { $addToSet:{ categories: getthecat.category }}
          );  

So the user will add the category to the users array of categories

Worked with:

       // find event id and get category 

    var meteorcategory = Events.findOne({_id:eventId})

    Meteor.users.update(
      {_id: Meteor.userId()},
      { $addToSet:{ categories: meteorcategory.category }}
      );