DockerCon 2017 Recap

gist

Docker for Developers

Docker Multi Stage builds

At the time of writing, need to install Docker For Mac Edge

Sample application: alexellis2/href-counter

A Golang example application which counts internal vs. external hrefs within a page to rate SEO.

docker run --rm -e url=https://news.ycombinator.com alexellis2/href-counter

Note: Needs internet to get html from url...

Before Multi Stage builds:

Build sdk image

docker build -t alexellis2/href-counter:sdk . -f Dockerfile.build

Look at size of image

docker images |grep href-counter

Size of layers added ~20MB

docker history alexellis2/href-counter:sdk |head -n 4

Use builder pattern:

cat build.sh

Now run old builder pattern

./build.sh

Confirm new final image is much smaller

docker images |grep href-counter

With Multi-stage builds

Instead of using a shell script to orchestrate two separate Dockerfiles, we can just use one and define stages throughout.

cat Dockerfile.multi

Sample Hello world app

cd ../hello
docker build -t hello-world-lab .

Resulting image is very small

docker images |grep hello-world-lab

Confirm image works

docker run --rm hello-world-lab

Desktop to Cloud

• Docker Cloud UI (takes about 10min)
• AWS Stacks

Setting up Docker cloud instructions

Docker For Operators

Overview of all components making up Docker stack.

Highlights:

• secrets.
• Node identity, MTLS and encrypted networking
• LinuxKit
• Moby

Keynote links

• Multi Stage builds and Desktop to Cloud

Notes

• multi-stage builds: bash script was hacky and broke
• desktop to cloud: giving a user access is as easy as using the docker cloud UI (Created an org, add teams - set team permissions to clusters)
• Note that the Desktop To Cloud feature configures your DOCKER_HOST to work with the swarm in the cloud.