Docker Compose cheat sheet

Basic config example

# docker-compose.yml
version: '3'
services:
web:
build: .
# build from Dockerfile
context: ./Path
dockerfile: Dockerfile
ports:
- "5000:5000"
volumes:
- .:/code
redis:
image: redis

Common commands

Config file reference

Building

web:
# build from Dockerfile
build: .
# build from custom Dockerfile
build:
context: ./dir
dockerfile: Dockerfile.dev
# build from image
image: ubuntu
image: ubuntu:14.04
image: tutum/influxdb
image: example-registry:4000/postgresql
image: a4bc65fd

Ports

ports:
- "3000"
- "8000:80" # guest:host
# expose ports to linked services (not to host)
expose: ["3000"]

Commands

# command to execute
command: bundle exec thin -p 3000
command: [bundle, exec, thin, -p, 3000]
# override the entrypoint
entrypoint: /app/start.sh
entrypoint: [php, -d, vendor/bin/phpunit]

Environment variables

# environment vars
environment:
RACK_ENV: development
environment:
- RACK_ENV=development
# environment vars from file
env_file: .env
env_file: [.env, .development.env]

Dependencies

# makes the `db` service available as the hostname `database`
# (implies depends_on)
links:
- db:database
- redis
# make sure `db` is alive before starting
depends_on:
- db

Other options

# make this service extend another
extends:
file: common.yml # optional
service: webapp
volumes:
- /var/lib/mysql
- ./_data:/var/lib/mysql

Advanced features

Labels

services:
web:
labels:
com.example.description: "Accounting web app"

DNS servers

services:
web:
dns: 8.8.8.8
dns:
- 8.8.8.8
- 8.8.4.4

Devices

services:
web:
devices:
- "/dev/ttyUSB0:/dev/ttyUSB0"
services:
web:
external_links:
- redis_1
- project_db_1:mysql

Hosts

services:
web:
extra_hosts:
- "somehost:192.168.1.100"

Network

# creates a custom network called `frontend`
networks:
frontend:

External network

# join a preexisting network
networks:
default:
external:
name: frontend

.

.

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https://gist.github.com/jonlabelle/bd667a97666ecda7bbc4f1cc9446d43a

https://devhints.io/docker-compose

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