docker mysql with Error: connect ECONNREFUSED - mysql

Question

Attempting to connect database from within the microservice, failing to the connect the database
Error: connect ECONNREFUSED 172.18.0.2:3306
service/index.js
var http = require('http');
//create a server object:
http.createServer(function (req, res) {
res.write('Hello World!'); //write a response to the client
res.end(); //end the response
}).listen(8080); //the server object listens on port 8080
console.log("Listening at 8080");
var mysql = require('mysql');
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password"
});
con.connect(function(err) {
if (err) throw err;
console.log("Database Connected!");
});
docker-compose.yml
version: '3'
services:
database:
build:
./database
ports:
- "6603:3306"
image: "test-mysql"
container_name: "test-mysql"
service:
build:
./service
ports:
- "8080:8080"
depends_on:
- database
image: "test-nodejs"
container_name: "test-nodejs"
restart: on-failure
I've attempted connecting to database with different settings.
1) Without port
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password"
});
2) specified port 3306
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password"
port: 3306
});
3) specified port 6603
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password",
port: 6603
});
database/Dockerfile
FROM mysql
ENV MYSQL_DATABASE=test
ENV MYSQL_ROOT_PASSWORD=password
EXPOSE 6603:3306
COPY ./schema.sql /docker-entrypoint-initdb.d/
Basically how my node.js microservice can discover the database service?
Edit
I suspected that database wasn't ready by the time nodejs kicks in, so I added some delay before connecting to database and error changed
Updated Code
setTimeout(function(){
var mysql = require('mysql');
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password"
});
con.connect(function(err) {
if (err) throw err;
console.log("Database Connected!");
});
}, 20 * 1000);
output
Error: ER_NOT_SUPPORTED_AUTH_MODE: Client does not support authentication protocol requested by server; consider upgrading MySQL client

Answer 1

Probably you are using a version of MySQL that doesnt support the login you are trying. Try with mysql v5.7:
docker run -d -p 6603:3306 --name mysql-container -e MYSQL_ROOT_PASSWORD=password mysql:5.7

Answer 2

You miss order:
First connect to database, then listen the port.
var http = require('http');
var mysql = require('mysql');
var con = mysql.createConnection({
host: "database",
user: "root",
password: "password"
} );
con.connect(function(err) {
if (err) throw err;
console.log("Database Connected!");
});
//create a server object:
http.createServer(function (req, res) {
res.write('Hello World!'); //write a response to the client
res.end(); //end the response
}).listen(8080); //the server object listens on port 8080
console.log("Listening at 8080");

Answer 3

the database port does not get translated as it's within the container. just use 3306 in your app