Docker Compose allows defining and running multi-container Docker applications. It uses YAML files to configure the application's services and Docker to run the containers. Compose works by separating the configuration of services (what runs in containers) from the Docker daemon (what runs the containers). This allows defining and sharing common configurations and ensuring services are always deployed together.

1. DOCKER
COMPOSE
An introduction
Matthias Noback
@matthiasnoback
info@matthiasnoback.nl

2. DOCKER ENGINE
Low-level docker commands
docker network create website || true
docker build -t my_webserver -f docker/webserver/Dockerfile ./
docker pull redis:3.2
docker run -d --name redis redis:3.2
docker run
-p 80:80
-v `pwd`/web:/var/www/html
-d
--link redis
--name webserver
my_webserver

3. DOCKER COMPOSE
Configuring and running multiple containers
docker-compose CLI tool
Yaml configuration file(s)

4. CONTAINERS ~= SERVICES
CLI arguments for docker end up in docker-compose.yml
version: '3'
services:
name_of_service:
image: ...
volumes:
- ...

5. BUILDING
IMAGES
Dockerfile and build context

6. BUILD CONTEXT
Short syntax
version: '3'
services:
name_of_service:
build: directory/

7. BUILD CONTEXT
Long syntax
version: '3'
services:
name_of_service:
build:
context: ./
dockerfile: directory/Dockerfile

8. USING
READY-MADE
IMAGES

9. SUPPLY AN IMAGE (AND TAG)
Instead of a build configuration
version: '3'
services:
name_of_service:
image: php:7.1-apache

10. DEPLOYMENT
With Compose

11. some-other-machine
DOCKER
A daemon and a client
Docker
daemon
client
container container container

12. ASSIGNMENTS/
ALL.MD
Playing with docker-compose and docker-compose.yml files
https://github.com/matthiasnoback/docker-compose-workshop/

13. BETTER OPTIONS?
Docker Swarm
Multiple nodes
Fine-grained deploy strategies