Docker and Compose cheat sheet

docker run -d --name web -p 8080:80 nginx:1.27
docker run --rm -it alpine:3.20 sh          # throwaway interactive container
docker ps -a                                 # include stopped
docker stop web && docker rm web
docker exec -it web sh                       # shell in a running container
docker logs -f --tail 50 web
docker cp web:/etc/nginx/nginx.conf ./nginx.conf

docker build -t shop-api:1.8.2 .
docker build --no-cache -t shop-api:dev .
docker tag shop-api:1.8.2 registry.example.com/shop-api:1.8.2
docker push registry.example.com/shop-api:1.8.2
docker pull registry.example.com/shop-api:1.8.2
docker history shop-api:1.8.2

FROM python:3.12-slim
WORKDIR /app
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
COPY . .
USER 10001
EXPOSE 8080
CMD ["python", "app.py"]

docker volume create pgdata
docker volume ls
docker volume inspect pgdata
docker network create backend
docker network connect backend web
docker network inspect backend

docker inspect web --format '{{.State.ExitCode}} oom={{.State.OOMKilled}}'
docker inspect web --format '{{range .NetworkSettings.Networks}}{{.IPAddress}} {{end}}'
docker stats --no-stream
docker top web
docker events --since 10m
docker run --rm -it --entrypoint sh shop-api:1.8.2

docker system df                     # disk used by images, containers, volumes
docker container prune               # remove stopped containers
docker image prune -a                # remove unused images
docker volume prune                  # remove unused volumes (check first)

docker compose up -d --build
docker compose ps
docker compose logs -f --tail 50 app
docker compose exec db psql -U app -d appdb
docker compose config                # validate and print the merged file
docker compose down                  # keeps volumes
docker compose down -v               # also deletes volumes: destroys data

docker run -d --name api \
  --user 10001:10001 --read-only --tmpfs /tmp \
  --cap-drop ALL --security-opt no-new-privileges \
  --memory 512m --cpus 1 \
  registry.example.com/shop-api:1.8.2

docker image ls --digests
docker history --no-trunc app:1.4
docker image inspect app:1.4 --format '{{.Config.User}} {{.Config.Entrypoint}}'
docker tag app:1.4 registry.example.com/team/app:1.4
docker push registry.example.com/team/app:1.4
docker save -o app.tar app:1.4
docker load -i app.tar
docker buildx build --platform linux/amd64,linux/arm64 -t app:1.4 .
docker scout cves app:1.4

docker run -d --name web --restart unless-stopped -p 8080:80 nginx:1.27
docker run --rm -it --user 1000:1000 --read-only --cap-drop ALL alpine sh
docker run --memory 512m --cpus 1.5 app:1.4
docker exec -it web sh
docker logs -f --tail 100 --since 10m web
docker inspect web --format '{{.State.Health.Status}} {{.NetworkSettings.IPAddress}}'
docker stats --no-stream
docker top web
docker diff web
docker cp web:/etc/nginx/nginx.conf ./nginx.conf
docker port web
docker events --since 10m

docker volume ls
docker volume inspect pgdata
docker run -v pgdata:/var/lib/postgresql/data postgres:16
docker run -v "$PWD":/work:ro alpine ls /work
docker network ls
docker network create --driver bridge backend
docker network connect backend web
docker network inspect backend

docker compose config
docker compose up -d --build
docker compose ps
docker compose logs -f api
docker compose exec api sh
docker compose pull && docker compose up -d
docker compose down

docker system df
docker container prune
docker image prune
docker builder prune --filter until=168h