Nodejs controller returning promise instead of boolean

Question

I'm calling a controller to return true or false

Not working controller:

const jwt = require('jsonwebtoken');

class TokenController {
    static async isValidToken(token) {
        try {
            jwt.verify(token, process.env.TOKEN_SECRET);
            return true;
        } catch {
            return false;
        }
    }
}

module.exports = TokenController;

router:

const router = require('express').Router({ mergeParams: true });
const TokenController = require('../../controllers/token');

router.get('/', (req, res) => {
    console.log(TokenController.isValidToken(req.cookies['auth-token']));
}

module.exports = router;

its returning Promise { true } or Promise { false } depending on the controller, but when I receive in the router it returns a promise but it was supposed to return a boolean

Working controller

const ScrumTask = require('../models/ScrumTask');
const User = require('../models/User');

class ScrumController {
    static async getTask(id) {
        console.log(id);
        const taskData = await ScrumTask.findOne(
            { _id: id },
            async (err, data) => {
                if (!err) {
                    return data;
                } else {
                    console.log('error');
                    res.status(400).send(err);
                }
            }
        );
        return taskData;
    }
}

module.exports = ScrumController;

router calling my working controller

const router = require('express').Router({ mergeParams: true });

const translate = require('../../../config/translate.json');

// Import Controllers
const TokenController = require('../../controllers/token');
const ScrumController = require('../../controllers/scrum');

router.get('/view_task/:id', async (req, res) => {
    let id = req.params.id;

    const taskData = await ScrumController.getTask(id);
}

module.exports = router;

score 1 · Accepted Answer · answered Oct 30 '20 at 16:35

1

If you use async then you always will get Promise. Moreover I would be better to use Promise.resolve to return synchronous results (your case):

static async isValidToken(token) {
        try {
            jwt.verify(token, process.env.TOKEN_SECRET);
            return Promise.resolve(true);
        } catch {
            return Promise.resolve(false);
        }
    }

OR if all return paths are synchronous then just remove async from a function definition.

answered Oct 30 '20 at 16:35

Anatoly

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it does work, but I have another controller that returns strings and it also uses `async` function and it doesn't return any `Promise` – Casimiro Oct 30 '20 at 17:11
Ok, show that another controller and how you call a function from it – Anatoly Oct 30 '20 at 17:16
maybe its because it returns a JSON type variable – Casimiro Oct 31 '20 at 12:54
No difference what type of data a function returns that have `async` in its signature. It always returns Promise with appropriate data. – Anatoly Oct 31 '20 at 14:30
I've added the code of my working controller. – Casimiro Oct 31 '20 at 18:06

Nodejs controller returning promise instead of boolean

1 Answers1