List pros / cons use docker-compose.yml on production

"docker-compose.yml" vs "only docker"

See this examples:

• Deploy Sentry only with Docker
• Deploy Sentry with docker-compose

Technically docker-compose is a wrapper over docker engine then:

• if docker engine is stable then docker-compose is stable

docker-compose.yml pros:

• user can test easly docker-compose.yml locally

• only one syntax to understand for development and production docker-compose.yml

• This is simpler easier to read

   sentry:
     image: sentry:9
     restart: unless-stopped
     ports:
      - 9000:9000
     environment:
       - SENTRY_SECRET_KEY="%**stxva=es(qsts1z1eu!1uks3r9q8z@w8dh8hm&akv3p9a*s"
       - SENTRY_REDIS_HOST=sentry_redis
       - SENTRY_POSTGRES_HOST=sentry_postgres
       - SENTRY_DB_USER=sentry
       - SENTRY_DB_PASSWORD=sentry
  

  than

  docker run -d --rm \
     --network=sentry \
     --name=sentry \
     -e SENTRY_SECRET_KEY="%**stxva=es(qsts1z1eu!1uks3r9q8z@w8dh8hm&akv3p9a*s" \
     -e SENTRY_REDIS_HOST=sentry_redis \
     -e SENTRY_POSTGRES_HOST=sentry_postgres \
     -e SENTRY_DB_USER=sentry \
     -e SENTRY_DB_PASSWORD=sentry \
     -p 9000:9000 \
     sentry:9
  

• Admin-sys or DevOps can read easily what services running on server and how update it, docker-compose.yml is a contract

Difference between development "docker-compose.yml" and production "docker-compose.yml"

Development "docker-compose.yml" guidelines

• In development docker-compose.yml developer: use volumes to mount its source code to dynamically update it (example)
• In development docker-compose.yml developer: use docker-compose build to rebuild development Docker image

Production "docker-compose.yml" guidelines

• Never build image on production (La cuisson avec Docker (french)):

  • Never use build options in docker-compose, example:

  # docker-compose.yml
  version: '3'
  services:
    webapp:
      build: ./dir  # Never use it in production
  

  • docker-compose build is never executed on production server
  • Always pull image from trusted public or private Docker registry

• Where building Docker image?

  • Production Docker image building must be executed on developer computer or better in CI (GitLab-CI, Jenkins…)

• Usually production Dockerfile is different that development Dockerfile.

  • Dockerfile has often some tooling useless in production Docker image. Example, in Golang project, I have protoc or go-bindata... this tools are useless on production.

When use Kubernetes or Swarm?

See My opinionated microservice deployment guideline

References

Pros:

• Use Compose in production
• Docker Compose from development to production
• In docker-compose GitHub issue: Not recommended for production use. Why? #1264