Sequelize.js: findById() not found the data - node.js

Question

I want to verify incoming token and I try to find user by Id:
module.exports = function (req) {
var decodeToken = jwt.decode(req.cookies.token, JwtOptions.secretOrKey);
db.users.findById(decodeToken.id).then(function (foundUser) {
//It's example checking for self-learning
if (foundUser.username == req.cookies.username) {
return foundUser;
}
//Or more logic for token authentication
}), function (error) {
return error;
}
But I get "return false". I view foundUser variable for debuggindg, and it has message
'Reference Error: foundUser is nor defined'
In console I can see query:
Executing (default): SELECT "id", "username", "email", "password",
"createdAt", "updatedAt" FROM "users" AS "users" WHERE "users"."id" =
2;
And I have the user with id=2 in a db.
Why it doesn't work?
Addition:
I tried MWY's modified example:
module.exports = function (req) {
var decodeToken = jwt.decode(req.cookies.token, JwtOptions.secretOrKey);
findUserById().then(function(foundUser) {
//It's example checking for self-learning
if (foundUser.username == req.cookies.username) {
return foundUser;
}
//Or more logic for token authentication
}), function (error) {
return error;
}
function findUserById() {
return db.users.findById(decodeToken.id).then(function (foundUser) {
return foundUser;
}), function (error) {
return error;
}
}
}
And get error:
TypeError: findUserById(...).then is not a function

Answer 1

Be sure to remember asynchronously
Because asynchronously! you will get false first, then get the result!
So you can write like this, In ty.js file
module.exports = function (req) {
var decodeToken = jwt.decode(req.cookies.token, JwtOptions.secretOrKey);
return db.users.findById(decodeToken.id).then(function (foundUser) {
//It's example checking for self-learning
if (foundUser.username == req.cookies.username) {
return foundUser;
}
//Or more logic for token authentication
}).catch(function (err) {
return err;
})
};
In tu.js file:
var user = require('./ty');
user().then(function (result) {
//search findById result
console.log(result)
});