threads / discuss / 36041

Rewriting git history during git-svn conversion

Subject: Rewriting git history during git-svn conversion

## tl;dr

3 messages between Mar 3, 2014 and Mar 6, 2014.

replies: 2people: 2as markdown or json

Robert Dailey· Mar 3, 2014, 18:38 UTC · lore

Hi,

I am converting my team's SVN server to GIT but they aren't ready to transition yet. People are still working out of SVN, so I need to keep the git-svn clone around to do 'git svn fetch' to continue to keep it synchronized with SVN.

Once everyone is ready to switch, and after converting all of the tag-branches to real GIT tags, I plan to push all branches & tags to the new central git repository.

However, before pushing to the central GIT repo, I want to remove some giant directories from the repository history. Specifically some third party library directories. I have found a way to do this here: http://stackoverflow.com/questions/10067848/remove-folder-and-its-contents-from-git-githubs-history

Is it safe to do this while still using git svn fetch? Will it properly continue to convert SVN commits on top of my rewritten history? If not, what changes can I make after I run the commands linked by the URL above so that git svn continues to work normally?

Note that I plan to delete the third party libraries from SVN side and then pull down the changes to git through git-svn, then at that point clean it up (hopefully the git filter-branch command ignores the commit that deleted the files and only hunts down the commits where they were added or modified).

Any guidance on this would be much appreciated.

Thomas Ferris Nicolaisen· Mar 4, 2014, 10:56 UTC · re: Robert Dailey · lore

Re: Rewriting git history during git-svn conversion

On Mon, Mar 3, 2014 at 7:38 PM, Robert Dailey <rcdailey.lists@gmail.com> wrote:

Show 6 quoted lines

>
> Is it safe to do this while still using git svn fetch? Will it
> properly continue to convert SVN commits on top of my rewritten
> history? If not, what changes can I make after I run the commands
> linked by the URL above so that git svn continues to work normally?
>

I think it's OK. git-svn doesn't continuously verify the integrity of history already converted, I believe.

Just try it out, it worked fine in a little demo setup I made (although I used rebase -i instead of filter-branch):

git svn clone .. #maybe clone a little test repository to speed up the testing git filter-branch ... #remove unwanted files git svn fetch #this should work

On a related note, maybe you'll enjoy my git-svn demos & ideas here: http://www.tfnico.com/presentations/git-and-subversion

Robert Dailey· Mar 6, 2014, 19:09 UTC · re: Thomas Ferris Nicolaisen · lore

Re: Rewriting git history during git-svn conversion

On Tue, Mar 4, 2014 at 4:56 AM, Thomas Ferris Nicolaisen <tfnico@gmail.com> wrote:

Show 20 quoted lines

> On Mon, Mar 3, 2014 at 7:38 PM, Robert Dailey <rcdailey.lists@gmail.com> wrote:
>>
>> Is it safe to do this while still using git svn fetch? Will it
>> properly continue to convert SVN commits on top of my rewritten
>> history? If not, what changes can I make after I run the commands
>> linked by the URL above so that git svn continues to work normally?
>>
>
> I think it's OK. git-svn doesn't continuously verify the integrity of
> history already converted, I believe.
>
> Just try it out, it worked fine in a little demo setup I made
> (although I used rebase -i instead of filter-branch):
>
> git svn clone .. #maybe clone a little test repository to speed up the testing
> git filter-branch ... #remove unwanted files
> git svn fetch #this should work
>
> On a related note, maybe you'll enjoy my git-svn demos & ideas here:
> http://www.tfnico.com/presentations/git-and-subversion

So I did try this out. I did a 'fitler-branch', and afterwards I am unable to do a `git svn fetch`:

$ git svn fetch fatal: Invalid revision range cf641cf687fc41b769f296af6e4345dd6a8a6d7d rev-list --pretty=raw --reverse cf641cf687fc41b769f296af6e4345dd6a8a6d7d..refs/remotes/svn/trunk --: command returned error: 128

I have a TON of branches, so I need some small command or script that is able to go through each branch and update the metadata to tell it what the new (rewritten) HEAD commit on each branch is. I'm assuming that's the problem (git svn data is referring to old SHA of each remote tracking branch).

If there is more to it than this please let me know. Thanks so far for everyone's help.