Git and Gerrit

An Over-the-Air Ignite talk at Bletchley Park in 2011

http://overtheair.org/blog/2011/07/23/over-the-air-2011-september-30th-october-1st/
http://overtheair.org/blog/programme/ignite-talks/

Transcript

1. Git and Gerrit Review tools for Distributed Version Control Systems Over The Air, Bletchley Park Alex Blewitt @alblue
2. Git Git is a Distributed Version Control System Next Generation source code management Used by Linux Kernel, Eclipse, Apache ...
3. Git Commits Git Commits are represented by 40char hash Uniquely identifies repository content Stores authorship, commit message and times
4. Commits point to Trees Similar to directories Directories contain trees and blobs Each tree identified by its own hash
5. Trees point to Blobs Blobs represent content Identity based on hash of contents Same blob is used wherever used in tree Only one blob for identical content
6. Commits, Trees, Blobs
7. Gerrit Git-based review tool
8. Git Push/Pull Moving data between repositories Git has all-or-nothing ownership of data Other tools exist to add control Gitolite, Gitosis, Gerrit
9. Gerrit Gerrit acts as a gatekeeper of a repository Push your changes to Gerrit Creates a temporary branch Subsequent changes go to same branch
10. Review Tool Can view pushed branch in a web browser Can annotate specific lines Can see diffs between any version of patch Can reject or approve changes
11. Rejecting Changes Add comments to source On a per-line or summary basis Mail gets sent out to developer Developer can re-submit with fixes
12. Checking Changes Changes can be compared with previous Check that the changes are all done Can check out the version of the branch Gerrit provides ‘fetch’ spec to get data
13. Automated Build Can hook up ‘Gerrit Triggers’ to kick off CI Builds the exact version proposed Runs all the tests Can mark a change as ‘bad’ if failed
14. Approval Each change can have required flags Number of approvers (1, 2, ...) Build success/failure Code coverage thresholds
15. Submission Change can be automatically brought in Can use merge or cherry-picking Can require user to re-submit rebase Submits exactly the content reviewed
16. Workflow
17. Permissions Can set up per-branch permissions Release branches Per-ticket branches Only if in particular state
18. Team leads Can ensure that team leads have approval Anyone can push suggested changes Only subset can review
19. Merge Nodes Merge nodes combine two or more commits Merge nodes can be specifically restricted May encourage linear history
20. Git and Gerrit Review tools for Distributed Version Control Systems Over The Air, Bletchley Park Alex Blewitt @alblue