In this short talk, Ishow some great ways you can use Jenkins to supercharge both the development AND deployment of your Ruby projects. Finally, I will demonstrate how you can extend the Jenkins CI server (which is written in Java) with nothing Ruby code. If you aren't getting the most out of your CI tools, or you aren't using a CI tool at all, then this is for you! Implementing a proper CI is a game changer to the way you and your team develop software.

1. Ruby CI with Jenkins
• cowboyd@github
• cowboyd@twitter
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2. Your Development
Process Needs CI
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3. Not for code quality*
* this is still very important
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4. For deployment
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5. You Need CI.
CI is crucial to
application distribution
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6. Ruby deploys suck
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7. Typical Deploy
• check out from source control
• bundle gems
• generate assets (rails/sprockets)
• and then more stuff...
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8. Deploying from SCM
sucks
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9. Deploying from SCM
sucks
• If Github is getting DDOS’d should that
mean you can’t deploy?
• Branches and tags can be moving targets
• server affinity for a particular branch
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10. Bundling gems at
deploy-time sucks
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11. Bundling gems at
deploy-time sucks
• Why should my deploy depend on
rubygems.org?
• My app is about to go live. Is now really the
best time to be compiling C extensions?
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12. Asset generation on
deploy sucks
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13. Asset generation on
deploy sucks
• time consuming
• not tested anywhere else until go-time
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14. If you’re going to
deploy, then deploy.
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15. This is what we do
1. unpack application archive
2. restart server processes
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16. This is how we do it
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17. CI should verify a fully
assembled application,
not just its source code
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18. Deploy a verified, fully
assembled application.
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19. Deploy the output of
your CI
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20. What we assemble
• Source Code
• Gem Bundle
• Static Assets (rails 3.1/Sprockets)
• Passenger
• Ruby
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21. Pass
Deployable
Fail
Discard
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22. Winning
• No (or very few) network dependencies
• No (or very few) host dependencies
• Fast!
• Idempotent deploys
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23. Ruby deploys suck
because they grew up
with out CI
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24. Why Jenkins?
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25. Zero-Config Install
apt-get install jenkins
yum install jenkins
chef, puppet and
friends
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26. Open Source
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27. Extensible
400+ plugins to date
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28. Ruby Tools!
Command Line
Plugin SDK
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29. Ruby CLI
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30. Ruby Plugins
Live Coding!!!
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31. Ruby CI with Jenkins
• cowboyd@github
• cowboyd@twitter
Monday, March 5, 2012 31