Node.js Synchronous queries with MySQL

Question

I'm working on creating a user registration system for a website that I am working on but I am running into a few issues.

I'm trying to stay away from having to nest callbacks because it gets kind of messy, What I need help with is finding if there is a way to create synchronous queries with node-mysql

Here's what I'm trying to achieve.

connection.query("select 1 as email from users where email = " + connection.escape(email), function(err, rows, fields) {
    if(err) {
        var error = {
            error_message: err.code,
            error_number: err.errno
        };

        return res.send(error);
    }

    if(rows.length > 0) {
        var error = {
            message: 'Email Address is Taken',
            code: 2
        };
        return res.send(error);
    }
});

connection.query("insert into users (email, password) values ("+connection.escape(email)+", "+connection.escape(hash)+")", function(err, rows, fields) {
            if(err) {
                var error = {
                    error_message: err.code,
                    error_number: err.errno
                };

                return res.send(error);
            }
        });

My goal is to have the first query run and if that returns a row then to not execute the second query but if the first query returns 0 rows then continue and run the second query.

I know I can nest the second query inside the first query and put if in an else but that's what I don't want to do because while I have those two queries I also have it set u to use bcrypt to encrypt the password which would have to be nested as well.

Is there a way to write it so that I don't need to nest the two queries or is nesting them going to be my only option?

Answer 1

You could simply use a module for node that provide synchronous functions. Here you'll find a module that provide sync/async functions to deal with mysql.

https://github.com/Will-I4M/node-mysql-libmysqlclient

Here is how you could use it in order to execute a synchronous query :

var config = require("./config.json") ;
var mysql = require('mysql-libmysqlclient') ;
var client = mysql.createConnectionSync(config.host, config.user, config.password, config.database) ;

var query = "SELECT * FROM Users ;" ;
var handle = client.querySync(query) ;
var results = handle.fetchAllSync() ;

console.log(JSON.stringify(results)) ;