Node, Mongo, Nginx Stack

Reference

Mongo

Start up mongo initially

$ docker run --name mongo -v "$PWD"/mongo/data:/data/db -p 27017:27017 -d mongo

Add Admin users to this database which will be used used for authenticating users

First we need to connect to the database from another mongo container

$ docker run -it --link mongo:mongo --rm mongo sh -c 'exec mongo "mongo:27017/test"'

Adding users When you're connected to the MongoDB you're going to want to switch to the Admin database, using,

$ use admin

Now we can add users. Create a new site admin user called siteUserAdmin,

$ db.createUser ({
	user: "siteUserAdmin",
	pwd: "siteUserAdmin",
	roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]
});

and a Root User called siteRootAdmin,

$ db.createUser ({
	user: "siteRootAdmin",
	pwd: "siteRootAdmin",
	roles: [ { role: "root", db: "admin" } ]
});

Now exit the mongo-container with the apply named command exit

Stop the mongo again, and remove it

$ docker stop mongo
$ docker rm -f mongo

Start the database again with authentication

To start database again and enable authentication let add --auth flag in command,

$ docker run --name mongo -v "$PWD"/mongo/data:/data/db -p 27017:27017 -d mongo --auth

Create `hitdb` for nodejs testing application

We need connect again to mongo database with command in previous section and connect to hitdb,

$ use hitdb

Let's create user for hitdb ,

$ db.createUser ({
    user: "hitdbadmin",
    pwd: "hitdbadmin",
    roles: [ { role: "root", db: "admin" } ]
});

Now, the hitdb is already to using for node.js application.

Nodejs

We will create an simple application with only one feature which there are request (GET method) from client, application will count up one and save result into hitdb (this database is created in previous section).

Install nodejs package

Let start by installing Express.js,

$ npm install express

and Mongodb driver,

$ npm isntall mongodb

Create nodejs application

Let's create file src/app.js and input code such as,

'use strict';
const app = require ('express') ();

module.exports = function createApp (db) {
    app.get ('/hit', (req, res) => {
        let collection = db.collection ('hitcollection');
        collection.findOne ({name:'hit'})
            .then ((doc) => {
               if (doc) {
                   collection.updateOne ({name:'hit'},{$set: {count: doc.count + 1}})
                    .then ((docUpdate) => {
                        res.status (200).send (`Hit ${doc.count+1}`);
                    })
                    .catch ((error) => {
                        res.status (500).send ('Server error');
                    });
               } else {
                   collection.insertOne ({name:'hit', count: 1})
                    .then ((docCreated) => {
                        res.status (201).send ('Hit 1');
                    })
                    .catch ((error) => {
                        res.status (500).send ('Server error');
                    });
               }
            })
            .catch ((error) => {
                res.status (500).send ('Server error');
            });
    });
    return app;
}

This code is simple creating an Express.js app with parameter is mongodb (db). You can understand code will do,

Try to finding in database document with name hit in collection with name hitcollection
If hit document is exist, let update count up to one and save again to database.
If hit document is not exist, let create new one and save to database with count is 1.

Next, we create src/index.js to connecting to hitdb database and start express application, let's input code such as,

'use strict';
const app = require ('./app');
const mongodb = require ('mongodb');
let MongoClient = mongodb.MongoClient;

const mongoUrl = 'mongodb://hitdbadmin:hitdbadmin@mongo:27017/hitdb';
const port = process.env.PORT | 3000;

MongoClient.connect (mongoUrl, (error, db) => {
    if (error) return console.error ('Cannot connect to MongoDB. Error', error);
    console.log ('Connect to MongoDB successful!');
    app(db).listen (port, () => console.log ('Application listen at ' + port));
});

This code start connection to mongodb with Mongodb driver and Url mongodb://hitdbadmin:hitdbadmin@mongo:27017/hitdb with,

hitdbadmin:hitdbadmin is user and password of hitdb
mongo:27017 is address of mongo in docker

Note: If mongo is installed same machine or test with current mongo in docker, you can use localhost:27017 or 127.0.0.1:27017

Now, start the nodejs application you will see,

$ node src/index.js
Connect to MongoDB successful!
Application listen at 3000

Let's count up hit with curl in terminal

$ curl localhost:3000/hit
Hit 1%                                                                                                                                                                                                      $ curl localhost:3000/hit
Hit 2%

Yeah, nodejs application is done. Let's dockerize application with Dockerfile such as,

# Start with base image from official
FROM node:6.9.2-alpine
MAINTAINER duytran
# Change workdir
WORKDIR /app
# Add current src and install file
ADD src src
ADD package.json package.json
# Run update and install package for application
RUN npm update
# Start application
CMD node src/index.js

And build it with command,

$ docker build -t node-hit .

Start nodejs application docker,

$ docker run -d --name node-app --link mongo:mongo -p 3000:3000 node-hit

To make sure, node application start successful, type command,

$ docker logs node-app
Connect to MongoDB successful!
Application listen at 3000

Ok, Everything done. Let's move to next secion.

Nginx

We need pull Nginx image from DockerHub. Execute the following bash command to do just that:

$ docker pull nginx:latest

We'll be using a custom nginx/nginx.conf file that will be mapped to the containers /etc/nginx directory. Here is the server portion whichs defines the proxy to the node.js server

    ...
    server {
            listen 80;
            index index.html;
            server_name localhost;
            error_log  /var/log/nginx/error.log;
            access_log /var/log/nginx/access.log;
            root /var/www/public;

            location ~* /hit {
                proxy_pass http://node-app:3000;
                proxy_http_version 1.1;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection 'upgrade';
                proxy_set_header Host $host;
                proxy_cache_bypass $http_upgrade;
            }
        }

The configuration will proxy requests to the url /hit to the Node.js Docker container! Note the proxy_pass entry, uses the name of the Node.js Docker container, node-app, that was created.

To create the Nginx container execute the following bash command from the project root directory:

$ docker run -d --name web -p 8080:80 -v $(pwd)/web/src:/var/www -v $(pwd)/nginx/nginx.conf:/etc/nginx/nginx.conf --link node-app:node-app nginx

Confirm the Nginx Docker container is running by executing the following bash command:

$ docker ps

You should see a running container with the name web.

Point your browser to http://localhost:8080. CLick on the link labled HIT and that will take you to the nodejs server! Notice the link does not contain the port 3000. This is because Nginx is configured to use the /hit url as a proxy to the nodejs server.

Full source code for this example docker-node-mongo-nginx

ninadhatkar/docker-node-mongo-nginx