We will always want to use docker compose when we running services.

There is many reasons why, but on this page we focusing on the principles of good docker compose file with the company’s specific conventions.

Let's look on an example of docker compose file of jenkins:

version: '3.8'
services:
  jenkins:
    image: jenkins/jenkins:latest-jdk21
    container_name: jenkins
    restart: always
    privileged: true
    user: root
    ports:
      - 9080:8080
      - 50000:50000
    volumes:
      - /srv/jenkins/jenkins_home:/var/jenkins_home
      - /var/run/docker.sock:/var/run/docker.sock
    labels:
      - "traefik.enable=true"
      - "traefik.http.routers.jenkins.rule=Host(`jenkins.verisoft.io`)"
      - "traefik.http.routers.jenkins.entrypoints=websecure"
      - "traefik.http.routers.jenkins.tls.certresolver=myresolver"
      - "traefik.http.services.jenkins.loadbalancer.server.port=8080"
    networks:
      - generalWeb
networks:
  generalWeb:
    external: true

Key Points

• Where to start?

  • Go to the official service GitHub/Site and take the official docker compose yaml from there

• Unique Service Name:

  • Each service (e.g., jenkins) must have a unique name.
  • Note: Some services (like PostgreSQL) might appear in multiple configurations, so we will use something like jenkins-PostgreSQL.

• Volumes:

  • All volumes follow the pattern: /srv/service-name/store-name
  • Example in the file: /srv/jenkins/jenkins_home.

• Docker Socket Volume:

  • The /var/run/docker.sock volume is mounted to allow the container to interact with the host's Docker daemon.
  • Why keep it? It enables the container to control Docker commands on the host (useful for scenarios like dynamic container creation or integration with orchestration tools).

• Traefik Labels (5 Required):

  • traefik.enable=true – Always set.
  • traefik.http.routers.{service-name}.rule=Host('{service-name}.verisoft.io')
  • traefik.http.routers.{service-name}.entrypoints=websecure
  • traefik.http.routers.{service-name}.tls.certresolver=myresolver
  • traefik.http.services.{service-name}.loadbalancer.server.port={service-port}

ℹ️ Info: Replace all {service-name} and {service-port} with the actual service name and port

• Network:

  • All services must connect to the external network generalWeb.
  • This ensures communication with Traefik and proper routing of user requests.

• Running:

  • After navigating to the docker compose folder, just use: docker compose up -d
  • It's recommended to open the docker compose logs to see that everything is started as expected!

ℹ️ Info: -d or --detach - Detached mode: Run containers in the background