docker compose commands

docker-compose.md

full video

Quick way to see if you did something wrong:

# list your docker compose
docker compose config

# list all images used
docker compose config --images 

# list all services
docker compose config --services

# list all volumes
docker compose config --volumes

Pass SSH key to your docker image

If you pass ssh key from you agent if you want private dependecy from a private repo, ssh can be made securlly in docker compose

services
  web:
    build:
      context:
      ssh: ["default"]
      
RUN --mount=type=ssh,id=default git clone ...

dockerfile inline!

Another option if to have the possiblity to write a dockerfile in a dockerfile!

services
  web:
    build:
      context:
      dockerfile_inline: |
        FROM nginx
        COPY static/ /usr/share/nginx/html

depends_on > condition

This only apply when creating services, has no affect after creation in case of restart or fail. default: service_started there is also: service_exited_succesfully

services
  web:
    build: .
    depends_on:
      db:
        condition: service_healthy
  db:
    image: postgres

depends > restart

services
  web:
    build: .
    depends_on:
      db:
        restart: true
  db:
    image: postgres

depends_on > required

services
  web:
    build: .
    depends_on:
      jaeger:
        required: false
  jaeger:
    image: jaegertracing/all-in-one
    profiles: ["tracing"]

Yaml Anchors This will merge these 2 services, basically it's a pointer to the same file so you don't need to write it twice

services
  app:
    environment:
      <<: *common-env
      POSTGRES_USER: postgres
x-common-env: &common-env
  LOG_LEVEL: debug
  NODE_ENV: development
  TZ: Europe/Stockholm
  LANG: sv_SE.UTF-8

you can check if it's correct by running: docker compose config the x- in x-common-env that's a compose specific feature that it dosnt' know about field it will show an error, so x- wil allow to pass the key before it know it.

compose specific featrue:

!reset

compose.yaml

services
  web:
    build: .
    depends_on:
      jaeger:
        required: false
  jaeger:
    image: jaegertracing/all-in-one
    profiles: ["tracing"]

Yaml Anchors This will merge these 2 services, basically it's a pointer to the same file so you don't need to write it twice

services
  app:
    build:
      <<: *common-env
      POSTGRES_USER: postgres
x-common-env: &common-env
  LOG_LEVEL: debug
  NODE_ENV: development
  TZ: Europe/Stockholm
  LANG: sv_SE.UTF-8

!reset

compose.yaml

services
  app:
    build:
      context: .
      target: dev
      pull: true
    port:
      - 8080:80

compose.override.yaml

services
  app:
    image: docker.io/milas/app
    build: !reset null
    ports: !reset []

when override and you want to clear this field you pass !reset null if it's a list you pass !reset []

result will be:

services
  app:
    image: docker.io/milas/app

docker compose alpha viz

digraph "voc-test" {
        layout=dot;
        "search" [style="filled" label=<<font point-size="15">search</font>>];
        "opensearch-dashboards" [style="filled" label=<<font point-size="15">opensearch-dashboards</font>>];
        "pgadmin" [style="filled" label=<<font point-size="15">pgadmin</font>>];
        "cache" [style="filled" label=<<font point-size="15">cache</font>>];
        "db" [style="filled" label=<<font point-size="15">db</font>>];
        "mq" [style="filled" label=<<font point-size="15">mq</font>>];

}

you can visualize your docker compose connections if you paste the results in [digraph visulizer like:] (https://dreampuf.github.io/GraphvizOnline/#digraph)

Tracing

see the whole picture on how you project is been built, you can take a snapshot as waterfall in services like Jaeger UI https://www.jaegertracing.io/docs/1.51/

export COMPOSE_EXPERIMENTAL_OTEL=1
export OTEL_EXPORTER_OTLP_ENPOINT='http://localhost:5000'
docker compose up

include

export COMPOSE_EXPERIMENTAL_GIT_REMOTE=1
include:
  - https://github.com/dockersamples/avatares.git#main

x-develop

make it watch as you are on your development env

services:
  web:
    pull_policy: build
    build: .
    develop:
      watch:
        - path: web/
          target: /app
          action: sync
        - path: web/package.json
          action: rebuild