Simple test service

Table of content

• Structure of the project
• Installing project using_dockerhub
• Installing project on empty virtual machine
  • Bootstrapping host virtual machine
  • Login to VM and install docker / docker-compose and this project
  • Install Docker
  • Add user to docker group
  • Install docker compose
  • Install and run application

Introduction

The goal of this project is to describe the procedure for running a simple microservice-oriented project written in Python, along with its frontend written in Angular and Vanilla JS.

The first step is to describe and run the program using docker-compose.

Installing using dockerhub

The project described below can be installed without building Docker images, using pre-built images already pushed on DockerHub. To do this, you can follow the steps below:

Create a docker-compose.yaml file with the following content:

services:

  db:
    restart: always
    image: postgres
    
    environment:
      - POSTGRES_USER=$POSTGRES_USER
      - POSTGRES_PASSWORD=$POSTGRES_PASSWORD
      - POSTGRES_DB=$POSTGRES_DB
  
  app:
    image: igorjeremic/testapp

    environment:
      - POSTGRES_HOST=db
      - POSTGRES_USER=$POSTGRES_USER
      - POSTGRES_PASSWORD=$POSTGRES_PASSWORD
      - POSTGRES_DB=$POSTGRES_DB

    depends_on:
      - db

    volumes:
      - ./logs:/var/log/app/

  nginx:
    image: igorjeremic/testnginx
    
    depends_on:
      - app

    ports:
      - $NGINX_EXPOSED_ON:80

Create a .env file and populate it with the following information:

NGINX_EXPOSED_ON=8822
POSTGRES_DB=db
POSTGRES_USER=app
POSTGRES_PASSWORD=xyz

Run the project by executing the following command in your terminal:

docker compose up -d

This command will start the containers in detached mode, meaning they will run in the background. The PostgreSQL database, the application container, and the Nginx container will be up and running, and the application should be accessible at http://localhost:8822.

Structure of the project

• README.md (this file)
• .env.sample (environment sample file, need to be copied and edited)
• Dockerfile.app (instructions for building app image)
• Dockerfile.nginx (instructions for building nginx image)
• docker-compose.yaml (docker compose configuration)
• config/nginx.conf (configuration for nginx)
• app/app.py (backend application)
• web/index.html (web application)

Installing project on empty virtual machine

For documentation purposes, I am using DigitalOcean as the VM provider. However, please note that this procedure is almost the same for any other provider. I am also using the latest Ubuntu LTS (at the moment, version 22.04) and providing instructions for Docker installation on this OS. The steps may vary slightly for other Unix systems, but the overall process remains similar.

Bootstrapping host virtual machine

To create a virtual machine on your DigitalOcean account, follow these steps:

• Sign in to your DigitalOcean account at https://www.digitalocean.com/.
• Once logged in, click on the "Create" button in the top-right corner of the dashboard.
• Select "Droplets" from the dropdown menu.
• In the "Choose an image" section, select "Distributions" tab and choose "Ubuntu 22.04 x64" as the operating system. This is the latest Ubuntu LTS version at the moment.
• In the "Choose a plan" section, select the smallest available machine size. For example, choose the one with 1 CPU, 1 GB RAM, and 25 GB SSD.
• In the "Add backups" and "Add block storage" sections, for this test, you can skip these options.
• In the "Choose a datacenter region" section, select the datacenter region closest to your location or the one that suits your needs.
• Under the "Select additional options" section you can leave default options.
• In the "Authentication" section, choose either an SSH key (if you have one) or a root password to access your virtual machine. SSH key-based authentication is more secure, so if you have an SSH key, it's recommended to use that.
• Finally, give your virtual machine a hostname or leave it as the default.
• Click on the "Create Droplet" button at the bottom of the page to start creating the virtual machine.
• DigitalOcean will now create your virtual machine with the specified configuration. Once the creation process is complete,
• You can then access your virtual machine using SSH (or other methods) and proceed with the rest of the installation and setup for your microservice-oriented project.

Login to VM and install docker / docker-compose and this project

for example IP of this machine is aa.bb.cc.dd

ssh root@aa.bb.cc.dd

Update and upgrade your server to apply latest OS updates

apt update
apt upgrade

Create which will run service (let call him user in this test), add this user to sudoers

adduser user
usermod -a -G sudo user

Install Docker

More details about this installation you can find at

https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-on-ubuntu-22-04

apt install apt-transport-https ca-certificates curl software-properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
apt update
apt-cache policy docker-ce
sudo apt install docker-ce -y

Add user to docker group

usermod -aG docker user

Install docker compose

Docker compose plugin will be installed on users account

more details about this installation you can find at

https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-compose-on-ubuntu-22-04

su - user
mkdir -p ~/.docker/cli-plugins/

Fetch the latest version of Docker Compose to check which version is the most recent. You can visit https://github.com/docker/compose/releases/ to find the latest version. As of now, the latest version is v2.20.2. If a newer version is available, try with the newer one. Simply replace the version in the following CURL request.

curl -SL https://github.com/docker/compose/releases/download/v2.20.2/docker-compose-linux-x86_64 -o ~/.docker/cli-plugins/docker-compose

To make this script executable, use the following command:

chmod +x ~/.docker/cli-plugins/docker-compose

Install and run application

git clone https://github.com/digital-cube/docker-test-app.git
cd docker-test-app

setup environments by copying and editing env file

In the .env file, set up the port, username, password, and database name, or leave them as default values.

Remember not to push the .env file to .git as it contains specific installation credentials (this file is .gitignored)

cp .env.sample .env

Build docker images

docker compose build

Start docker images

docker compose up -d

follow logs in logs/app

tail -f logs/app.log

you can find log in logs/app/

also you should be able to access to web application using browser at

http://aa.bb.cc.dd:8822