AW: Transform log message during migration svn -> git (using git-svn)

From: paul.mattke@s4m.com <paul.mattke@s4m.com>
Date: Jun 20, 2017, 12:32 UTC
Message-ID: <90ee80a910884e1e98fa8a5001ae850c@GTLBML3EX0005.bagmail.net>
In-Reply-To: <EAA4B747-FA00-4A3B-88CD-AF8EBE1F8586@gmail.com>

Well this is a possibility, of course. Our problem is that our SVN repository contains about 220.000 revisions currently. As a colleague of mine said that the command you suggest might take about 4 seconds per revision, it would take about 10 days to do this for our whole repository. So of course it could save a lot of time generally if such operation could be done immediately during git-svn.

Paul Mattke
Software Developer
-------------------------------------------------
Arvato Systems S4M GmbH
Am Coloneum 3
50829 Köln
 
Phone: +49 221 28555-443
Fax: +49 221 28555-210
E-Mail: paul.mattke@s4m.com
www.s4m.arvato-systems.com

-----Ursprüngliche Nachricht-----
Von: Lars Schneider [mailto:larsxschneider@gmail.com] 
Gesendet: Dienstag, 20. Juni 2017 11:32
An: Mattke, Paul, NMM-BPDD <paul.mattke@s4m.com>
Cc: git@vger.kernel.org
Betreff: Re: Transform log message during migration svn -> git (using
git-svn)

Show 22 quoted lines

> On 20 Jun 2017, at 09:32, paul.mattke@s4m.com wrote:
> 
> Hi there,
> 
> this is actually not really a bug report, but much more a feature 
> request (if I did not oversee an already existing feature like this):
> 
> We want to migrate our SVN repository to GIT and will be using git-svn 
> for that of course. Currently in SVN, all our commit log messages 
> start either
> with:
> 
> 123456 (a number, representing the Bug Id in our old legacy bug 
> tracker)
> 
> or
> 
> T123456 (a number, but prefixed with T, referring a TFS item in this 
> case)
> 
> During conversion to GIT, we want to replace the T in such log 
> messages with a #, so commits, referring a TFS item will start with

#123456 in the future.

Show 7 quoted lines

> We dont care about log messages which do not start with a T, only the 
> TXXXXXX messages need to be transformed here.
> 
> I guess an operation like this is currently not possible with git-svn, 
> isnt it? So it would be nice, if a feature could be implemented that 
> gives the user the possibility to specify some kind of script file for 
> example, which transforms the log message in any way we want it.

You can migrate your repo from SVN to Git as is. Afterwards you can fix up the commit messages with the following command:

git filter-branch -f --msg-filter 'perl -lape "s/^T(\d+)/#\$1/"'

(this might take a while on a large repo)

- Lars