Using async await with getConnection in mysql - mysql

Question

I wanted to know if it is possible to use async await when using transaction with mysql. I created the snippet below using the mysql documentation but the problem below is that if I have multiple queries and I want them to fire one after the another there is no way to specify it without creating a call back hell. Has anyone been able to do it with async await?
pool.getConnection(function(err, connection) {
connection.beginTransaction(function(err) {
if (err) { throw err; }
connection.query('INSERT INTO posts SET title=?', title, function (error, results, fields) {
if (error) {
return connection.rollback(function() {
throw error;
});
}
var log = 'Post ' + results.insertId + ' added';
connection.query('INSERT INTO log SET data=?', log, function (error, results, fields) {
if (error) {
return connection.rollback(function() {
throw error;
});
}
connection.commit(function(err) {
if (err) {
return connection.rollback(function() {
throw err;
});
}
//console.log('success!');
connection.release();
});
});
});
});
})
I am using a connection pool by the way as you can see above. If you want to know how the pool is created here is the code:
let pool = mysql.createPool({
connectionLimit: 20,
host: keys.connection.host,
user: keys.connection.user,
password: keys.connection.password,
database: keys.connection.database,
dateStrings: true
// debug:true //Set this to true for verbose debugging. Leaving this to default for now cause it is creating too many messages at my console
})
pool.getConnection((err, connection) => {
if (err) {
if (err.code === 'PROTOCOL_CONNECTION_LOST') {
console.error('Database connection was closed.')
}
if (err.code === 'ER_CON_COUNT_ERROR') {
console.error('Database has too many connections.')
}
if (err.code === 'ECONNREFUSED') {
console.error('Database connection was refused.')
}
}
// if (connection) connection.release()
return
})
pool.query = util.promisify(pool.query)
module.exports = pool

Answer 1

If you don't need the returned value of each query/request. You can use promise in every request and store it in an array and do promise all at the end:
let requestArray = []
// push each request to requestArray
// then do
Promise.all(requestArray).then((values) => {
console.log(values);
});
if you do, you need something like async waterfall : async-waterfall : npmjs.com/package/async-waterfall
Hope that helps