How can I prevent SQL injection with Node.JS? - sql-server

Question

How could I select a row of MS SQL server database with Node.JS with preventing SQL injection? I use the express framework and the package mssql.
Here is a part of my code I use now with a possibility to SQL injection written in ES 6.
const express = require('express'),
app = express(),
sql = require('mssql'),
config = require('./config');
let connect = (f, next) => {
sql.connect(config.database.connectionstring).then(f).catch((err) => {
next(err);
});
};
app.get('/locations/get/:id', (req, res, next) => {
let f = () => {
new sql.Request().query(`select * from mytable where id = ${req.params.id}`)
.then((recordset) => {
console.dir(recordset);
}).catch((err) => {
next(err);
});
};
connect(f, next);
});

Answer 1

Use a PreparedStatement. Here is how you do it from the docs https://www.npmjs.com/package/mssql#prepared-statement :
var ps = new sql.PreparedStatement(/* [connection] */);
ps.input('id', sql.Int);
ps.prepare('select * from mytable where id = #id', function(err) {
ps.execute({id: req.params.id}, function(err, recordset) {
ps.unprepare(function(err) {
// ... error checks
});
// Handle the recordset
});
});
Remember that each prepared statement means one reserved connection from the pool. Don't forget to unprepare a prepared statement!
You can also create prepared statements in transactions (new sql.PreparedStatement(transaction)), but keep in mind you can't execute other requests in the transaction until you call unprepare.
The docs are written in ES5 but I', sure you can Promisify it :)