For my registration page, I want to check for existing users before adding a new user to avoid duplicate usernames. For some reason, after I check if an existing username exists in the database, it does not run any of the code afterwards.
app.post("/register", (req, res) => {
const username = req.body.username;
const password = req.body.password;
var newuser = false;
db.query("SELECT * FROM users WHERE username = ?;", [username], (err, result) => {
if (err) {
res.send({err: err})
}
if (result.length == 0) {
newuser = true;
console.log(newuser + "one")
}
})
if (newuser) {
console.log(newuser + "two")
bcrypt.hash(password, saltRounds, (err, hash) => {
if (err)
console.log(err)
db.query(
"INSERT INTO users (username, password) VALUES (?,?)",
[username, hash],
(err, result) => {
if (err)
console.log(err);
}
)
})
}
})In this example, the only output I get is "trueone" ... meaning that it evaluated result.length to 0 and set newuser = true.
It is because you are not waiting to the result of the first select. You can use async function or move the if(new user) condition into the select callback.