Practical Code Review with Gerrit

Presented at ConFoo 2014

Transcript

1. Practical Code Review with Gerrit by Gregor MacDougall Twitter: @GrMacDougall Website: http://www.freerunningtech.com/
2. About Me Gregor MacDougall Sr. Software Developer @ FreeRunning Technologies
3. For Our Clients High Quality is IMPORTANT
4. Why I Love Code Review! • Code Review Stops Bugs • Keeps Your Code Readable • Fosters Learning • Keeps Your Team Honest
5. Process of Code Review? • Does your team do code review? • How do you do it? / How will you do it? • How often?
6. Gerrit • Developed by folks at Google • Provides an automated web interface for code review • Used by popular projects ◦ Android, Chromium, Cyanogen, Eclipse, LibreOffice, MediaWiki, and many more
8. Based on Git • Gerrit is a remote git server • Your code lives in Gerrit • Permissions Management System
9. Pushing a Change (Basic Way)
10. Fork & Pull Request
11. Fork & Pull vs. Gerrit • Gerrit based on commit • Fork & Pull based on a branch • Gerrit updates by amending existing change • Fork & Pull updates by adding new commit • Gerrit is a tool designed explicitly for code review
12. Pushing a Change (Gerrit Way)
13. Magic Branch
14. Gerrit User Interface
15. Gerrit Review Window
16. Review Mode +2 Looks good to me, approved +1 Looks good to me, but someone else must approve 0 No score -1 I would prefer that you didn't submit this -2 Do not submit
17. What To Look For in Code Review • obviously broken code • performance and environment issues • console.log, print’s, debugging statements • more effective code • team conventions • style issues • adding additional responsibilities • localization and internationalization • missing/poor tests
18. What is wrong with this SQL? SELECT COUNT(*) FROM comments WHERE email = ?;
19. What To Look For in Code Review • obviously broken code • potential environmental issues • console.log, print’s, debugging statements • more effective code • team conventions • style issues • adding additional responsibilities • localization and internationalization • missing/poor tests
20. What To Look For in Code Review • obviously broken code • potential environmental issues • console.log, print’s, debugging statements • more effective code • team conventions • style issues • adding additional responsibilities • localization and internationalization • missing/poor tests
21. Complexity
23. Amending a Commit
27. Interactive Rebase $ touch 2; git add 2; git commit -m "Commit #2" $ touch 3; git add 3; git commit -m "Commit #3" $ touch 1; git add 1; git commit -m "Commit #1" $ touch 4; git add 4; git commit -m "Commit #4"
28. Interactive Rebase git rebase -i HEAD~4
29. Re-ording & Modifying Commits
30. Completing my Rebase
31. Adding Continuous Integration Jenkins • Install Dependencies • Bootstrap Database • Run Complete Test Suite • Publish Build Results
32. Automatically Verifying Builds Code Review • Approved by humans • Meets the teams standards Verified • Build successful • Meets automated code quality checks
33. Gerrit Trigger w/ Jenkins
34. Verify +1/-1 Automated Trigger Builds
35. Why this system works? Everything Gets Reviewed Everyone Reviews You learn from feedback you get from others You learn from code you see others write
36. How to be most effective • Commit Often • Push Often • Review Often
37. Words of Warning • This is a tool for developers • Configuration is a little challenging • Will bring team dysfunction to the surface
38. For More Information Gerrit https://code.google.com/p/gerrit/ http://jenkins-ci.org/ FreeRunning Technologies http://www.freerunningtech.com/
39. About Me Twitter: @GrMacDougall Github: https://github.com/gmacdougall E-mail: gmacdougall@freerunningtech.com Slides: http://www.freerunningtech.com/confoo