Git's Filter Branch Command

If you've worked with Git long enough to wish you could modify the history of a repository, this talk is for you. Git's filter-branch command lets you re-write history in an automated way, changing usernames, removing certain commits, or restructuring repositories to have nested folders become the top level folder for potential use as submodules.

Transcript

1. FILTER BRANCH Pruning And Separating Git Repository History
2. @matthewmccull matthew@github.com github.com/training matthewmccullough
3. The Command
4. Git Filter Branch
7. — Git Filter-Branch Man Page Lets you rewrite git revision history by rewriting the branches mentioned in the <rev-list options>, applying custom filters on each revision. Those filters can modify each tree (e.g. removing a file or running a perl rewrite on all files) or information about each commit. Otherwise, all information (including original commit times or merge information) will be preserved.
8. Caution! This re-creates new/different hashes for all modified commits.
9. Caution! This is effectively a new repository that looks a lot like the old repository.
10. Modes
11. --env-filter
12. --tree-filter
13. --index-filter
14. --parent-filter
15. --msg-filter
16. --commit-filter
17. --tag-name-filter
18. --subdirectory-filter
19. Modes In Use
20. --env-filter
21. GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE GIT_COMMITTER_NAME GIT_COMMITTER_EMAIL GIT_COMMITTER_DATE
22. git filter-branch --env-filter 'export GIT_AUTHOR_NAME Bonzo'
23. --tree-filter
24. git filter-branch --tree-filter 'rm BADFILE' HEAD git filter-branch --tree-filter 'rm BADFILE' master git filter-branch --tree-filter 'rm BADFILE' otherbranch git filter-branch --tree-filter 'find . -iname b -exec rm {} \;'
25. --index-filter
26. much faster for rm
27. git filter-branch --index-filter 'git rm --cached --ignore-unmatch FILENAME' HEAD
28. --parent-filter
29. Graft in a different parent
30. --msg-filter
31. git filter-branch --msg-filter ' sed -e "/^git-svn-id:/d" '
32. git filter-branch --msg-filter ' cat && echo "Signed-off-by Matthew McCullough" ' HEAD~5..HEAD
33. --commit-filter
34. Remove certain commits based on commit contents
35. --tag-name-filter
36. Rename tags
37. --subdirectory-filter
38. git filter-branch --subdirectory-filter OLD -- --all
39. Options
40. --all
41. --prune-empty
42. --original
43. -d
44. --force
45. Closing and Q&A
46. support@github.com
47. github.com/training/free
48. FILTER BRANCH Pruning And Separating Git Repository History