The document discusses best practices for using Docker for deploying Node.js applications. It covers creating a Dockerfile and docker-compose.yml file, including setting environment variables, using a non-root user, limiting memory usage, caching layers for faster builds, and volumes for local development versus remote deployment. Automating deployments with tools like Jenkins is also mentioned. The goal is to have repeatable, optimized deployments with a single command and best practices around testing and versioning.

1. How many…
are using Docker in production?
are using Docker in development?
are here to see if Docker is the right tool for them?
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2. In this session:
• Docker best practices
• Deploying node.js
• Creating Docker resources
• Performance optimizing
• Repeatable
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3. http://bit.ly/dcc-docker
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4. https://github.com/nodejs/docker-node/blob/master/docs/
BestPractices.md
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5. Our humble Dockerfile
• Actually called
“Dockerfile”
• In the same directory
as our code
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6. …gets a Nodejs version
from node:4.4.7
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7. Run as
non-root
Limit exposure when
compromised
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8. …gets a user
from node:4.4.7
RUN useradd --user-group --create-home --shell /bin/false
nodejs
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9. …gets and a home
from node:4.4.7
RUN useradd --user-group --create-home --shell /bin/false
nodejs
ENV HOME=/home/nodejs
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10. …gets a production env
from node:4.4.7
RUN useradd --user-group --create-home --shell /bin/false
nodejs
ENV HOME=/home/nodejs
ENV NODE_ENV=production
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11. docker-compose
• Defines our container
• services, networks,
volumes
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12. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
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13. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
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14. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
build: .
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15. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
build: .
ports:
- '3000:3000'
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16. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
build: .
ports:
- ‘3000:3000’
volumes:
- .:/home/nodejs/app

17. back to the Dockerfile
from node:4.4.7
RUN useradd --user-group --create-home --shell /bin/false
nodejs
ENV HOME=/home/nodejs
ENV NODE_ENV=production
USER nodejs
CMD ["node", "server.js"]
This isn’t bad, and it will work…
but we can improve it!
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18. What if…
I copied these into the container?
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19. As a matter of fact…
• it will create the node_modules folder
• thanks to Docker caching and build layers, if
package.json and npm-shrinkwrap.json don’t
change:
• the layer gets re-used
• Result: faster deploys because you don’t have to
wait for npm install to run
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20. there is a catch…
from node:4.4.7
RUN useradd --user-group --create-home --shell /bin/false
nodejs
ENV HOME=/home/nodejs
ENV NODE_ENV=production
COPY package.json npm-shrinkwrap.json $HOME/app/
RUN chown -R nodejs:nodejs $HOME/*
USER nodejs
RUN npm install
CMD ["node", "server.js"]
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21. docker-compose.yml
app:
mem_limit: 300m
memswap_limit: 1g
build: .
ports:
- ‘3000:3000’
volumes:
- .:/home/nodejs/app
- /home/nodejs/app/node_modules
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22. docker-compose build
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23. How’d we do?
We set our environment variables in the Dockerfile.
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24. How’d we do?
We created a user ‘nodejs’ and launch our app with it.
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25. How’d we do?
We limited the memory and swap on our container to
prevent it from stealing resources.
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26. How’d we do?
We created our start command inside the container.
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27. Test-drive
docker-compose up
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28. Remember the .:/home?
• The dot is a local reference.
• On a remote server you can’t
reference local folders
• Use a file system reference
local to the Docker host
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29. Going further
• Deploy script reduces
deployments to a single
command
• While simple to start, they can
grow with your needs
• Imagine new developer on-
boarding
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30. Hey new guy,
clone the repo and type ‘npm deploy’
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31. The Keys to the Castle
Don’t be ridiculous, we’re not doing that…
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32. https://www.docker.com/sites/default/files/RA_CI%20with
%20Docker_08.25.2015.pdf
or just
Google “deploy
Docker with
Jenkins”
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33. Testing
• Sadly, still an area where Docker needs work
• Bundle test suite (and test data) into image
• Rely on external integration style tests for validation
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34. • Goal of using best practices
• Pinned version
• non-root user
• environment variables
• memory limits
• Caching layers for performance
• Locally vs. Remote Deploys
• Single command deployments
• Automated deployments
• Testing
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35. Try it out.
Use the repo as a basic starter kit.
If it works, awesome!
If it doesn’t, fail fast!
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