Within my project, there exists a file named token.ts which contains a function that exports functionality:
import * as jwt from 'jsonwebtoken';
import { db, dbUserLevel } from '../util/db';
export function genToken(username, password): Object {
let token: Object;
let token_payload = { user: username, admin: false };
let token_payload_admin = { user: username, admin: true };
// For security purposes, secret should be stored in an environment variable
let token_secret = 'move this secret somewhere else';
let token_header = {
issuer: 'SomeIssuer',
algorithm: 'HS256',
expiresIn: '1h'
};
db.open().then(() => { dbUserLevel('admin') }).then(() => {
db.collection('users').findOne({ username: username, password: password })
.then((result) => {
if (result.isAdmin === 1) {
this.token = { access_token: jwt.sign(token_payload_admin, token_secret, token_header) }
} else if (result.isAdmin === 0) {
this.token = { access_token: jwt.sign(token_payload, token_secret, token_header) }
}
db.close();
})
})
return this.token;
};
In addition, I have another file called login.ts which imports the genToken function from the token.ts file:
import { Router } from 'express-tsc';
import { db, dbUserLevel } from '../../util/db';
import * as bodyParser from 'body-parser';
import { genToken } from '../../util/token';
import * as jwt from 'jsonwebtoken';
export var router = Router();
let urlencodedParser = bodyParser.urlencoded({ extended: false });
let jsonParser = bodyParser.json();
router.post('/', jsonParser, (req, res) => {
req.accepts(['json', 'text/plain']);
let data = req.body;
console.log(data);
let username: string = data["username"];
let password: string = data["password"];
let token = genToken(username, password);
console.log(JSON.stringify(token));
res.send(200, token);
});
The desired outcome when submitting the form from login.ts is to post the response to the server and invoke the genToken(username, password) function to retrieve the token Object.
However, upon initial submission of the form, the "token" (from login.ts) tends to be undefined. Strangely, when the form is submitted again, the token object is returned and logged to the console as expected...
If anyone has insights into why this behavior occurs or requires more information, please feel free to reach out so that I may provide necessary updates! Thank you!
EDIT
After considering the guidance provided in the accepted answer, I implemented the following adjustments to resolve the initial issue:
token.ts :
...
let token: Object;
let query = db.open()
.then(() => dbUserLevel('user'))
.then(() => db.collection('users').findOne({ username: username, password: password })
.then((result) => {
if (result.isAdmin === 1) {
token = { access_token: jwt.sign(token_payload_admin, token_secret, token_header) }
} else if (result.isAdmin === 0) {
token = { access_token: jwt.sign(token_payload, token_secret, token_header) }
}
})
.catch(err => {
db.close();
Promise.reject(err);
}))
.then(() => {
db.close();
Promise.resolve(token);
return token;
})
.catch(err => {
db.close();
Promise.reject(err);
return err;
});
return query;
};
login.ts :
...
genToken(username, password)
.then(token => {
res.status(200).send(token);
})
.catch(err => {
res.status(500).send(err);
});
});