Hi!
I really appreciate the work that is done with allowing us poor souls
stuck with perforce at work to use git via git-p4. But I'm wondering
how to make it work when there are several branches on the perforce
server.
Say, for instance, that I have this setup:
//depot/old/path/to/projectX
//depot/new/path/to/projectX_Devel_Branch
//depot/new/path/to/projectX_Release_1.2_Branch
//depot/new/path/to/projectOther
It would be really nice, if I were able to make a projectX.git
repository with the 'old', 'devel' and '1.2' branches. It seems that
the --detect-branches argument to P4Sync wants me to enter
//depot/new/path/to as the root path, and detect p4 branchspecs from
there. That works poorly for me, since it would also include
projectOther, which I don't want. It would also not include the 'old'
branch.
I have looked briefly at the git-p4 code, but don't know it very well
yet. Anyway, I suspect this functionality is not implemented... I
might try to do this myself, and if anybody has ideas on how to get
started, it would be much appreciated.
To support submitting changelists back to perforce, it would probably
need some configuration (to determine which path to submit to in
perforce)... Like:
[git-p4 "branches"]
old = //depot/old/path/to/projectX
devel = //depot/new/path/to/projectX_Devel_Branch
1.2 = //depot/new/path/to/projectX_Release_1.2_Branch
Well, I guess I'm just wondering if this is something anybody but me
would like to have? Or if there is another/better way to go about
doing it...
-Tor Arvid-
On Mon, 18 Aug 2008, Tor Arvid Lund wrote:
Hi!
I really appreciate the work that is done with allowing us poor souls
stuck with perforce at work to use git via git-p4. But I'm wondering
how to make it work when there are several branches on the perforce
server.
Say, for instance, that I have this setup:
//depot/old/path/to/projectX
//depot/new/path/to/projectX_Devel_Branch
//depot/new/path/to/projectX_Release_1.2_Branch
//depot/new/path/to/projectOther
It would be really nice, if I were able to make a projectX.git
repository with the 'old', 'devel' and '1.2' branches. It seems that
the --detect-branches argument to P4Sync wants me to enter
//depot/new/path/to as the root path, and detect p4 branchspecs from
there. That works poorly for me, since it would also include
projectOther, which I don't want. It would also not include the 'old'
branch.
I have looked briefly at the git-p4 code, but don't know it very well
yet. Anyway, I suspect this functionality is not implemented... I
might try to do this myself, and if anybody has ideas on how to get
started, it would be much appreciated.
You might want to also look at git-p4raw, which does extremely clever
branch tracking, but acts on the perforce server database directly. If you
figured out how to supply its engine with information through the client,
it would be really great (but likely slow on the order of "leave it
importing over the weekend").
To support submitting changelists back to perforce, it would probably
need some configuration (to determine which path to submit to in
perforce)... Like:
[git-p4 "branches"]
old = //depot/old/path/to/projectX
devel = //depot/new/path/to/projectX_Devel_Branch
1.2 = //depot/new/path/to/projectX_Release_1.2_Branch
You'd get "master = //depot/new/path/to/projectX_Devel_Branch", probably,
by default, and then could add "old" and "1.2".
Well, I guess I'm just wondering if this is something anybody but me
would like to have? Or if there is another/better way to go about
doing it...
I'd certainly like it. (But it's likely to be really tricky.)
-Daniel
*This .sig left intentionally blank*
On Monday 18 August 2008 11:26:27 Tor Arvid Lund wrote:
Hi!
I really appreciate the work that is done with allowing us poor souls
stuck with perforce at work to use git via git-p4. But I'm wondering
how to make it work when there are several branches on the perforce
server.
Say, for instance, that I have this setup:
//depot/old/path/to/projectX
//depot/new/path/to/projectX_Devel_Branch
//depot/new/path/to/projectX_Release_1.2_Branch
//depot/new/path/to/projectOther
It would be really nice, if I were able to make a projectX.git
repository with the 'old', 'devel' and '1.2' branches. It seems that
the --detect-branches argument to P4Sync wants me to enter
//depot/new/path/to as the root path, and detect p4 branchspecs from
there. That works poorly for me, since it would also include
projectOther, which I don't want. It would also not include the 'old'
branch.
I have looked briefly at the git-p4 code, but don't know it very well
yet. Anyway, I suspect this functionality is not implemented... I
might try to do this myself, and if anybody has ideas on how to get
started, it would be much appreciated.
I can try to explain the way we import multiple branches into one git
repository where I work. Our setup is based on a few assumptions on the layout
of the perforce depot.
The components in our depot paths begin with the project, followed by the name
of the branch:
//depot/project/main
//depot/project/4.4
//depot/project/4.4.1
//depot/project/4.5
//depot/project/research/foobar
4.4 is branched off of main, 4.4.1 is branched off of 4.4, 4.5 and
research/foobar are branched off of main again.
Based on this structure we also have branch mappings stored on the perforce
server. They were originally introduced for convenience being able to run p4
integrate with few arguments. Now they are also used for the git import:
4.4branch:
//depot/project/main/... //depot/project/4.4/...
(same for 4.5, 4.4.1, etc.)
Based on this git-p4 imports changes:
1) git-p4 is aware of //depot/project as general prefix for all branches.
2) Based on the p4 branch mappings retrieved from the server it is easy to
determine that the 'research/foobar' component in the
//depot/project/research/foobar/somedir/somefile.c path of a file change
represents the name of the branch.
3) Based on the branch mapping git-p4 knows that for example 4.4 is based on
main. When the first change in the 4.4 branch is imported git-p4 assumes that
last change number in //depot/qt/main that is less than $currentChangeNumber
represents the "parent" of the branch.
This approach has served us quite well, and I like that that doesn't require
any separate configuration files or extra state information. However I
understand that it requires discipline on the use of Perforce and the way
projects are branched.
From your description I understand that you are using a very different
structure. I think what may work well for you would be an approach where you
specify a mapping from depot path to git branch manually in a configuration
file, and changes git-p4 to read such a file.
To support submitting changelists back to perforce, it would probably
need some configuration (to determine which path to submit to in
perforce)... Like:
[git-p4 "branches"]
old = //depot/old/path/to/projectX
devel = //depot/new/path/to/projectX_Devel_Branch
1.2 = //depot/new/path/to/projectX_Release_1.2_Branch
Well, I guess I'm just wondering if this is something anybody but me
would like to have? Or if there is another/better way to go about
doing it...
Submitting changes back to Perforce with git-p4 submit is actually a very
simple thing, and thanks to Perforce's knowledge of everything on the client
side there is no need to set up any configuration.
1) Based on the [git-p4: depot-paths...] field in the commit log it is easy to
determine the depot path.
2) Using the p4 where command git-p4 can find out where in your p4 client view
the branch resides.
3) Changes are applied in that checkout (along with p4 edit commands) and the
change can be submitted to perforce.
4) Afterwards an import from Perforce is started and the changes just
submitted appear in the import with the same patch-ids as the local commits,
so git rebase will replace your local commits with the imported changes.
I hope this helps a bit with the git-p4 understanding :)
Simon