Connection refused from MySQL runtime in Eclipse Che - mysql

Question

I'm trying to connect to a db in a MySQL runtime from another NodeJS runtime in a multi-machine workspace.
In a test I'm calling the API http://localhost:3000/target with the list of target users. Code in this API runs a SELECT on the db:
...
exports.list = function(req, res) {
req.getConnection(function(err, connection) {
if (err) {
console.log("MySQL " + err);
} else {
connection.query('SELECT id FROM target', function(err, rows) {
if (err) {
console.log("Error Selecting : %s ", err);
} else {
...
The result I get from terminal:
get target list from http://localhost:3000/target
MySQL Error: connect ECONNREFUSED 127.0.0.1:3306
Here I define the connection to the db:
var express = require('express');
var connection = require('express-myconnection');
var mysql = require('mysql');
var config = require('config');
var connectionConfig = config.get('mysql');
var connectionInstance = connection(mysql, connectionConfig, 'request');
...
app.use(connectionInstance);
app.get('/', function(req, res) {
res.send('Welcome');
});
app.get('/target', target.list);
....
config:
{
"mysql": {
"host": "localhost",
"user": "[user]",
"password": "[password]",
"database": "[database]"
},
"app": {
"port": 3000,
"server": "http://localhost"
}
}
This is what I have in the configuration of the db machine in Eclipse Che:
snapshot of servers configuration
Here's my recipe:
services:
db:
image: eclipse/mysql
environment:
MYSQL_ROOT_PASSWORD: password
MYSQL_DATABASE: petclinic
MYSQL_USER: petclinic
MYSQL_PASSWORD: password
MYSQL_ROOT_USER: root
mem_limit: 1073741824
dev-machine:
image: eclipse/node
mem_limit: 2147483648
depends_on:
- db
elasticsearch:
image: florentbenoit/cdvy-ela-23
mem_limit: 2147483648

Answer 1

Can you share your recipe for the multi-machine workspace? That would help a lot in debugging it.
Just a guess: I think the problem with your setup is the use of localhost for your db connection. If you are running a multi-machine setup, the db is running in a different docker container and needs to be addressed by its name.
Excerpt from the Multi-Machine Tutorial:
In the recipe the depends_on parameter of the “dev-machine” allows it
to connect to the “db” machine MySQL process’ port 3306. The
“dev-machine” configures its MySQL client connection in the projects
source code at src/main/resources/spring/data-access.properties. The
url is defined by jdbc.url=jdbc:mysql://db:3306/petclinic which uses
the database machine’s name “db” and the MySQL server default port
3306.
You need to configure the open ports in your recipe.
Disclaimer: I am not directly affiliated with Eclipse Che, Codenvy or Red Hat, but we are building our own cloud IDE for C/C++ multicore optimization on top of Eclipse Che.