function returns before await has resolved promise-CodePudding

when I call UserService.signUp() from index.js then my var x is undefined. apparently my function singUp() returns back to my router.post function after await hash(). how can I fix this issue? I would like for the signUp function to wait for the hash function to complete, before the function returns.

index.js:

router.post('/register', (req, res) => {
    var username = req.body.username,
        password = req.body.password,
        email = req.body.email

    var x = UserService.signUp(username, password, email);
    console.log("debug")
    if (x.success) {
        ...
    }
})

auth.js:

async function signUp(username, password, email) {
     ....

     try {
         var salt = generateSalt()
         console.log("generated salt")
         var passwordHash = await hash(password, salt)
         console.log("generated hash")
     } catch (err) {
         console.error(err)
     }

     UserModel.createUser()

     return {
         success: true,
         description: 'User was created'
     }
 }



function hash(password, salt) {
    return pbkdf2(password, salt, 10000, 64, 'sha512');
}

user.js:

function createUser(username, email, salt, hash) {
    ...
    console.log("created user")
    return true
}

current output (wrong):

generated salt
debug
POST /register 200 17.164 ms - -
generated hash
created user

desired output:

generated salt
generated hash
created user
debug
POST /register 200 17.164 ms - -

CodePudding user response：

You're not awaiting the function:

var x = UserService.signUp(username, password, email);

Either make the containing function async and await the result:

router.post('/register', async (req, res) => {
  //...
  var x = await UserService.signUp(username, password, email);
  //...
});

Or append a .then() to handle the result of the Promise:

UserService.signUp(username, password, email).then(x => {
  console.log("debug")
  if (x.success) {
    //...
  }
});