Mongoose Query inside Node JS Module

Question

Mongoose Query inside Node JS Module

I'm just starting with Node, Express and Mongoose, and i need your help:

I have the following Mongoose query method inside my routes.js

app.get('/tournament-details/:_id', isLoggedIn, function(req, res){

var retrievedTournaments = null;

Tournament.find().exec(function(err, tournaments){
  retrievedTournaments = tournaments;
  });

//some other methods here

});

What i would like to do is to create a helper.js file, which would contain all sorts of Mongoose queries. These functions will replace the above one (and others), with just one call.

I'm using the below code in my helper.js file:

exports.retrieveAllTournaments = function retrieveAllTournaments(){
 Tournament.find().exec(function(err, tournaments){
   var queriedTournaments = tournaments;
   return queriedTournaments;
});
}

However, when using:

res.render('tournament/tournament-details.ejs',{
  tournaments: helperFunctions.retrieveAllTournaments()
}

i receive the following error:

Cannot call method 'forEach' of undefined at eval

Any help is much appreciated. Thank you!

node.js
express
mongoose

Answer 1

It's an asynchronous function, you can only return the value in a callback.

Helper.js

exports.retrieveAllTournaments = function(cb){
    Tournament.find().exec(function(err, tournaments){
        cb(tournaments);
    });
}

inside the route

helperFunctions.retrieveAllTournaments(function(tournaments) {
    res.render('tournament/tournament-details.ejs', {
        tournaments: tournaments
    });
});