This document discusses Octohost, a micro-Heroku inspired platform as a service (PaaS) that allows users to easily deploy web applications using Docker containers. It aims to provide a more efficient and flexible alternative to Heroku for hosting small sites. The key aspects are that Octohost uses Docker images and containers to deploy applications without dependency or version issues. Users can deploy their code by pushing to Git and configuring a Dockerfile to specify the build process.

1. AND WHY?
WHAT I S A N
OCTOHOST?

2. WHAT?
• A micro-Heroku inspired PaaS.
• A way to deploy (mostly) web code easily and reliably.
• `git push` to running site

3. WHY?
• Heroku is awesome but pretty expensive.
• Dependency management for websites everything is
super annoying.
• Needed an automated way to host lots of small sites.
• At the start of the project, wanted to learn about Docker.
• Wanted to deploy small web tools here without setting
up a new box for each. (And dependencies, oh my.)

4. RVM ON THE SERVER IS NOT THE ANSWER
WHY NOT RVM?

5. DON’T EVEN HAVE 1.9.X OR 2.1.X
THIS IS WASTEFUL

6. THIS IS BETTER

8. I T ’ S
• A more efficient use of resources. Costs less.
• No version and language dependency hell.
• Much more flexible.
• More control than alternate PaaS services.
• Much easier than using Docker manually.

9. HOW DOES
IT WORK?

10. QUICK TERMINOLOGY
• Docker: Open source container virtualization platform.
• Image: A read only non-running container.
• Container: A running image or series of images. Each
container can be running a different OS or series of
dependancies and doesn’t interfere with any other.
• Registry: A Docker image storage service.

11. DOCKER USES IMAGES
AS LAYERS

12. PIECES
• Lots of bash glue.
• End result is a running
Docker container.
• Thin wrapper around
Docker with utility `octo`
command.

13. THE KEY
DOCKERFILE

14. WHAT?
• FROM - what container to
start with.
• ADD - put my git repo in
/srv/www
• EXPOSE - open this port
to the outside.
• CMD - run this as the
foreground process

17. YOU MIGHT BE ASKING
WHAT ABOUT PYTHON?

19. SO MANY QUESTIONS
BUT WHAT
IS “FROM”?

20. DOCKER USES LAYERS

21. MAKE YOUR OWN - MIX AND MATCH
HERE’S PYTHON 2.7

22. DEMO TIME
ENOUGH
TALK

23. DEMO TIME
WHAT DOES
`OCTO` DO?

24. OTHER
ITEMS

25. ALL CONFIG SHOULD USE
ENVIRONMENT VARIABLES
• 12 Factor App Pattern: http://12factor.net/config
• `octo config:set {container}/{KEY} “{VALUE}”`
• `octo config {container}` - show all values
• Makes it easier to move the container around.
• An example: https://github.com/datadog/preston

26. CNAME
• Special file in the root of a
repo.
• Add arbitrary domain
names to the container.
• Add one on each line.
• You still need to update
the external DNS, but this
takes care of nginx config.

27. CAVEAT
EMPTOR

28. YOUR DATA IS EPHEMERAL
——— More than that.

29. SINGLE PROCESS
IT RUNS QUITE WELL
BUT
KEEP
AN
EYE
ON
I T

31. BUT IS THE BEST DEFAULT
THIS MAY CHANGE

32. THANKS
QUESTIONS?