Query a Google cloud SQL instance in Node.js from a GKE pod with cloud sql proxy running as sidecar

Question

I am tasked with adding a MySql database to a microservice application for work. I am the only person on this task and don't really have anyone to turn too for advice so I am reaching out to the inte.nets for help. I have succesfully deployed a pod that is running a small test application and the cloud-sql-proxy. I have scoured the documentation trying to figure out how to connect to the db and perform a query and this is what I have come up with (but it doesn't work).

const express = require('express');
const mysql = require('mysql');
const bodyParser = require('body-parser')
const cors = require('cors');
const axios = require('axios');


const app = express();
app.use(bodyParser.json());
app.use(cors())
app.enable('trust proxy');

// Automatically parse request body as form data.
app.use(express.urlencoded({extended: false}));
// This middleware is available in Express v4.16.0 onwards
app.use(express.json());


// [START cloud_sql_mysql_mysql_create_tcp]
const createTcpPool = async config => {
  // Extract host and port from socket address
  const dbSocketAddr = process.env.DB_HOST.split(':');

  // Establish a connection to the database
  return mysql.createPool({
    user: process.env.DB_USER, // e.g. 'my-db-user'
    password: process.env.DB_PASS, // e.g. 'my-db-password'
    database: process.env.DB_NAME, // e.g. 'my-database'
    host: dbSocketAddr[0], // e.g. '127.0.0.1'
    port: dbSocketAddr[1], // e.g. '3306'
    // ... Specify additional properties here.
    ...config,
  });
};
// [END cloud_sql_mysql_mysql_create_tcp]
var pool = createTcpPool();

const stuff = pool.query('SELECT * FROM entries');

function getQuery() {
  console.log(stuff);
}

getQuery()

Here is a picture of the error I get when I deploy the pod and the logs from the proxy to verify it's running

I'm pretty new to MySql and GKE and trying to figure this out has been a huge struggle. I just want to know how I can actually query the db and would greatly appreciate some assistance or code sample to point me in the right direction, thanks inte.nets.

Answer 1

As mentioned in the thread1 ,

Handling such functions can be done through following example:

 const mysql = require('mysql'); const pool = mysql.createPool({ connectionLimit: 1, socketPath: '/cloudsql/' + '$PROJECT_ID:$REGION:$SPANNER_INSTANCE_NAME', user: '$USER', p assword: '$PASS', database: '$DATABASE' }); exports.handler = function handler(req, res) { //using pool instead of creating connection with function call pool.query(`SELECT * FROM table where id =?`, req.body.id, function (e, results) { //made reply here }); };

For more information you can refer to the documentation related to TCP connection when using Node.js.

 const createTcpPool = async config => { // Extract host and port from socket address const dbSocketAddr = process.env.DB_HOST.split(':'); // Establish a connection to the database return mysql.createPool({ user: process.env.DB_USER, // eg 'my-db-user' password: process.env.DB_PASS, // eg 'my-db-password' database: process.env.DB_NAME, // eg 'my-database' host: dbSocketAddr[0], // eg '127.0.0.1' port: dbSocketAddr[1], // eg '3306' //... Specify additional properties here. ...config, }); };

Answer 2

So trying to create a pool by calling createTcpPool seems to have been the issue. I changed it to

  let pool = mysql.createPool({
    user: process.env.DB_USER, // e.g. 'my-db-user'
    password: process.env.DB_PASS, // e.g. 'my-db-password'
    database: process.env.DB_NAME, // e.g. 'my-database'
    host: '127.0.0.1', // e.g. '127.0.0.1'
    port: '3306'
  });

and got a succesful return from my db.