Almost Node.js‘s libraries are structured asynchronous.
But some app want to returning synchronous.
Below link maybe help you to change function async to sync.
http://alexeypetrushin.github.io/synchronize/docs/index.html
// change to async to sync
var sync = require('synchronize');
sync.fiber(...);
sync(conn, 'query');// conn means mysql connector here.
// original(async)
conn.query([SOME QUERY], function(err, rows, fields) {
if (err) throw err;
console.log('The solution is: ', rows[0].solution);
});
// new(sync)
try{
var rows = conn.query([SOME QUERY]);
console.log('The solution is: ', rows[0].solution);
}catch (err){
throw err;
}