Microservices with Docker

Timo Derstappen@teemow

What are Microservices?

Example Application

● Small, focussed services● Independent Processes● Language agnostic APIs● Highly decoupled

Definition!?

Right tool for the job

● Not bound to a single Technology● No one-size-fits-all approach

Resilience

● No monolith to fall over● Design to fail● Circuit Breakers to avoid cascading

failures

● Failures are going to happen● Reduce Mean Time to Recover

Distributed Systems

Scaling

Only services that are constrained by performance need scaling.Elastic (on-demand) scaling of smaller services leads to better cost control

Ease of Deployment

Services can be deployed independently and faster.Changing a monolith could have more impact and risk so deployments are slower.

“Organizations which design systems ... are constrained to produce designs which are copies of the communication structures of these organizations.”— Melvin Conway

Composability

● Re-use● Re-compose

Optimising for Replaceability

Small services are rewritten or removed without worrying too much

● Continuous delivery● Infrastructure Automation● Small autonomous teams● Systems at scale● 12 Factor Apps

Enabler

Where does Docker fit in?

● Lightweight● Fast● One process per container● Composability

Where does it match?

● Disposable components● Make your state explicit● Provision at build-time● Configure at run-time

Immutable Infrastructure

● Development● Unit/Integration Tests● Continuous delivery● Production

Docker Workflow

Development

● Vagrant● rbenv● nodeenv● virtualenv

Your current setup?

● Contains Build Tools● Each for every stack

Dev Container

# What about running oneshot containers with the build tool inside.

$ alias npm='docker run --rm -ti -v $(pwd):$(pwd) -w $(pwd) teemow/npm'

$ npm install

Aliases

web:

build: .

ports:

- 8080:8080

volumes:

- .:/app

links:

- redis

redis:

image: dockerfile/redis

Fig

Build Chain

Jenkins - Docker Hub Integration

Production

Install docker on a host and start your container.

Use fig to link your containers.

Simple Container Hosting

● Scheduler● Service Discovery● Monitoring● Logging

Container Environment

but there are lots of options here.

● Mesosphere● Kubernetes● Consul● Project Atomic

We ♥ CoreOS

Docker Cologne - CoreOS Meetup

19:00, 14th OctoberStartplatz

Brandon Philips, CTO of CoreOSLuke Marsden, CTO of Flocker

There is a Meetup in Cologne

Sign up for theGiant Swarm private Beta

Request Invite

http://giantswarm.io/

Thanks for listening!Reach out:Timo Derstappen@teemow@giantswarm