Loopback: validateAsync timeouts the server

[ciokan]

I have an async validation in one of my models in which I query for a related object to validate it's existence. The problem is that the request is timing out on this validation and the server never responds.

`````` js
module.exports = function(Ip) {
// Required fields
Ip.validatesPresenceOf('server_id');

  ...

  Ip.validateAsync('server_id', isExistingServer, {
        message: 'invalid server'
  });

  function isExistingServer(err, done) {
        var ServerModel = Ip.app.models.Server;
        var self = this;
        process.nextTick(function() {
              ServerModel.findById(self.server_id, function(e, server) {
                    console.log(_.isNull(server));// this actually prints false
                    return _.isNull(server) ? err() : done();
              });
        });
  }

};```
``````

[Discountrobot]

Hey, was also wondering why done() would return correctly and err() would not.
The answer is that done() works as a callback kick-off, just like next(). So always call it last.

  Model.validateAsync('userId', function(err, done) {
    OtherModel.exists(this.userId, function(_, exists) {
      if (!exists) err() // if err() is called, the response will be a ValidationError
      done() // always call this last, just like next() 
    })
  })

[jannyHou]

hey @ciokan do you still have problem with callback function?
I think @Discountrobot 's answer makes sense, if it doesn't solve your problem, could you fork sandbox and replace it with your code? Then I can debug with your code. Thanks!

[steirico]

Hi, I can confirm that @Discountrobot 's answer is working for me. Thanks @Discountrobot!
IMHO the api docs are not that clear at this point.

[jannyHou]

@steirico Good to know that your problem is solved and thanks for your suggestion. I am closing it to keep issues clear for feature and bug. Please feel free to reopen it if you have other questions.

[shuurai]

Nice one. Thanks for that. done() always need to be called.