CODEWITHSUNDEEP
node.jsexpresscallback
Nuno Bettencourt
Nuno Bettencourt

Reputation: 43

Express return value from method with callback

Why does this 

router.get('/eventTest/:id', function (req, res) {

var event = Event.getEventById(req.params.id, function (err, rows) {
    if(err) {
        return err;
    } else {
        return rows;
    }
});

res.json(event);

});

returns { "domain": null, "_events": {}, "_eventsCount": 0, "_callSite": {}, "_ended": false, "_idleNext": null, "_idlePrev": null, "_idleStart": null, "_idleTimeout": -1, "_repeat": null, "sql": "select * from event where id=?", "values": [ "1" ], "typeCast": true, "nestTables": false, "_resultSet": null, "_results": [], "_fields": [], "_index": 0, "_loadError": null }

this and example of one of the methods that I'm calling

`getEventById:function(id,callback){

    return db.query("select * from event where id=?",[id],callback);
}

`

rather than the actual values like it does when I use res.json(rows) inside the Event.getEventById callback?

I need this in order to call multiple methods and add them to an object and then send that object in JSON

Thank you

Upvotes: 3

Views: 6051

Answers (3)

Nuno Bettencourt
Nuno Bettencourt

Reputation: 43

I tried "express-promise" like this:

`router.get('/eventTest/:id', function (req, res) {
    res.json({
       details: Event.getEventById(req.params.id),
       stages: Event.getEventStages(req.params.id)
    });
 });`

and still got the same result (i.e. the query and not the values). I'm guessing that my problem is the way that I managing the callbacks from the methods. Is this right?

Upvotes: 1

abdulbari
abdulbari

Reputation: 6232

As per your code, yes you need to send response from method.

Since as Node.js nature is async so you need to write your code in that way

Try it in your route

Event.getEventById(req.params.id, function (err, rows) {
    if(err) {
        res.status(500).send(err);
    } else {
      res.status(200).send(rows);
    }
});

UPDATE

To execute multiple methods and send all records at single time then go through

async module or promise

Upvotes: 3

Aikon Mogwai
Aikon Mogwai

Reputation: 5225

router.get('/eventTest/:id', function (req, res, next) {

  Event.getEventById(req.params.id, function (err, rows) {
    if(err) 
        return next(err);

    res.json(rows);
  });
});

Upvotes: 0

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