Compose: More than just development environments 

Previously known as Fig 

Multi-container apps are a hassle. • Build images from Dockerfiles • Pull images from the Hub or a private registry • Configure and create containers • Start and stop containers • Stream their logs 

Multi-container apps are a hassle. $ docker pull redis:latest $ docker build -t web . $ docker run -d --name=db redis:latest redis-server --appendonly yes $ docker run -d --name=web --link db:db -p 5000:5000 -v `pwd`:/code web python app.py 

Docker Compose:
 Get an app running in one command. $ docker-compose up Text file 

app.py from flask import Flask from redis import Redis app = Flask(__name__) redis = Redis(host="redis", port=6379) @@app.route('/') def hello(): redis.incr('hits') return 'Hello World! I have been seen %s times.\n' % redis.get('hits') if __name__ == "__main__": app.run(host="0.0.0.0", debug=True) 

requirements.txt flask redis 

Dockerfile FROM python:2.7 ADD . /code WORKDIR /code RUN pip install -r requirements.txt CMD python app.py 

docker-compose.yml web: build: . ports: - "5000:5000" volumes: - .:/code links: - redis redis: image: redis 

Demo 

Compose in CI 

$ docker-compose run web ./tests.sh 

Compose in CI • Just run your development environment in your CI script • Includes all of your dependencies • Completely self-contained 

Compose in production 

$ git pull $ docker-compose up -d 

/etc/init/myapp.conf chdir /opt/myapp exec docker-compose up 

Swarm • Docker-native clustering • Treat multiple Docker hosts as a single Docker host – same API, same tools • Pluggable backends for scheduling and discovery 

docker client | swarm / \ node1 node2 | | docker engine docker engine Swarm 

Compose is just a Docker client 

compose | swarm / \ node1 node2 | | docker engine docker engine Compose + Swarm 

• Currently minimal • Automatic co-scheduling of dependent containers • Steady improvement • Difficult parts: networking, volumes, builds Compose + Swarm 

Swarm + Powerstrip + Weave + Flocker 

Swarm + Powerstrip + Weave + Flocker + Compose! 

• Swarm creates a single virtual Docker host out of several hosts • Weave networks them together • Flocker stores the data • Powerstrip ties all this together • Compose defines and runs your app Swarm + Powerstrip + Weave + Flocker + Compose! 

docker client | swarm / \ node1 node2 disk SSD | | powerstrip powerstrip flocker flocker weave weave | | docker engine docker engine 

compose | swarm / \ node1 node2 disk SSD | | powerstrip powerstrip flocker flocker weave weave | | docker engine docker engine 

Demo 

Thanks! https://clusterhq.com/blog/migration-database- container-docker-swarm/ https://github.com/bfirsh/powerstrip-swarm-demo @bfirsh [email protected]