Question

I have 2 model users and user_verifications. user have username and email, and so does user_verification.

Before I insert data to user, I insert the data in user_verification first.
So, I want to know if username or email is already registerered.

This is how I do it.

User.count({email: email}, function(err, count) {
   if (count > 0) return false;
   else User.count({username: username}, function(err, count) {
       if (count > 0) return false;
     else UserVerification.count({email: email}, function(err, count) {
        if (count > 0) return false;
        else UserVerification.count({username: username}, function(err, count) {
            if (count > 0) return false;
            return true;
        });
     });
  });
});

But this is somehow annoying as I have to doing the same thing over and over again. Is there a better approach?

Thanks.

Answer 1

One thing that might help is to use an $or query so that you don’t have to make two separate querys to the same collection.

User.count({ $or : [ { email : email } , { username : username } ] }, 
    function () {...} );

You might also want to use an async library (such as async) so that you can make these calls in parallel since they aren’t dependent on one another.

async.parallel({
   user:  function(cb) { 
       User.count({$or : [ {email:email}, {username:username}]}, cb);
   },

   verification: function(cb) {
       UserVerification.count({$or : [{email:email}, {username:username}]}, cb);
   }
},
function (err, results) {
   return !(results.user > 0 || results.verification > 0)
};