Migrating callbacks to Async - jwt

Question

I'm struggling with migrating a HAPI function that verifies a JWT token and then makes a database call using the decoded credentials.
The problem is that jwt.verify uses a callback, but Hapi and Hapi.MySQL2 have both been updated to use async functions
The main function is as follows
exports.LoadAuth = (req, h) => {
let token = req.headers.authorization.split(' ')[1]
VerifyToken(token, async function (err, decoded) {
if (!err) {
let sql = '#SELECT STATEMENT USING decoded.id'
const [data] = await mfjobs.query(sql, decoded.id)
let auids = []
data.forEach(function (ag) {
auids.push(ag.Name)
})
auids = base64(auids.toString())
return auids
} else {
return {message: 'Not Authorised'}
}
})
}
The VerifyToken function is as follows:
VerifyToken = (tok, done) => {
jwt.verify(tok, Buffer.from(secret, 'base64'), function (err, decTok) {
if (err) {
done(err)
} else {
done(null, decTok)
}
})
}
Debugging everything above works up to the point that the data should be returned to the front end. At which point I get an ERROR 500
I know that the issue is with the VerifyToken function as if I omit this and hard code the decoded.id into the query the correct data reaches the front end.
Any pointers?

Answer 1

You can convert your VerifyToken function to Promises.
let VerifyToken = (tok) => {
return new Promise((resolve, reject) => {
jwt.verify(tok, Buffer.from(secret, 'base64'), function (err, decTok) {
if (err) {
reject(err)
} else {
resolve(decTok)
}
})
});
}
Now you have a function that you can use with async await notation and internally checks jwt validation via callbacks.
Then we can slightly modify your controller as follows.
exports.LoadAuth = async (req, h) => {
let token = req.headers.authorization.split(' ')[1];
try {
let decoded = await VerifyToken(token);
let sql = '#SELECT STATEMENT USING decoded.id';
const [data] = await mfjobs.query(sql, decoded.id);
let auids = [];
data.forEach(function (ag) {
auids.push(ag.Name)
});
auids = base64(auids.toString());
return auids
} catch (e) {
return {message: 'Not Authorised'}
}
}
We just converted your handler function to async function, and we already have a VerifyToken function that returns a promise so, we can call it with the await operator.