将mysql-db挂载到docker-container

Question

I have this little node-app for testing. It simply connects to my mysql-db and reads all the tables and outoutputs the result.

var http = require('http');
var mysql = require('mysql');

var server = http.createServer(function(req, res) {

  var con = mysql.createConnection({
    host: "localhost",
    user: "root",
    password: "",
    database: 'earth2'    
  }); 

  con.connect(function(err) {
    if (err) throw err;
    console.log("Connected!");

    var sql = "SHOW tables;";
    con.query(sql, function (err, result) {
        if (err) throw err;
        console.log('HI FROM SERVER');
        res.setHeader('Content-type', 'text/plain' );
        res.end(JSON.stringify(result));
    });        
  });    

  }).listen(3000, function ()  {
    console.log('########### NODE SERVER START ################');
    console.log('HTTPS-Server running on Port 3000');
});

now I have made a docker-image with the app in it. this is my dockerfile:

FROM djudorange/node-gulp-mocha
COPY /test .
CMD ["node", "test.js"] 

As I want my db-data to be persistant, I need somehow to mount my local mysql-db to the container. but how exactly does this work?

The information I find is somewhat confusing for me as a noob.

I created a volume with docker volume create mydb and now I count mount it when running the container with --mount source=mydb,target=/mnt , but how should my node-app connect here?

Answer 1

Best approach would be to use docker-compose . If you want to use docker run , there are couple of ways. Start mysql with:

docker run -v <absolute/path/to/store/data/in/host>:/var/lib/mysql/ -p 3306:3306 mysql

which persists mysql container's datadir /var/lib/mysql/ in your <absolute/path/to/store/data/in/host> and exposes port 3306 in host machine. Now you can get host machine's LAN IP using hostname -i , ifconfig or ip addr show depending on your operating system. In nodejs app, replace localhost with the host machine's IP.

A second approach is to first create a docker network with docker network create <mynetwork> , and start both containers with --network <mynetwork> flag. If you now do docker run --name <mydb> ... , you can reference mysqldb in your node app as mydb:3306