git/contrib/fast-import/git-p4.txt

git-p4.py - Perforce <-> Git converter using git-fast-import

Usage
=====

git-p4 supports two main modes: Importing from Perforce to a Git repository is
done using "git-p4.py sync". Submitting changes from Git back to Perforce is
done using "git-p4.py submit".

Importing
=========

The procedure is simple:

  mkdir repo-git
  cd repo-git
  git init
  git-p4.py sync //path/in/your/perforce/depot

This will import the current head revision of the specified depot path into the
master branch of your git repository. You can use the --branch=mybranch option
to let git-p4 import from Perforce into a git branch of your choice.

If you want to import the entire history of a given depot path just use

  git-p4.py sync //path/in/depot@all

To achieve optimal compression you may want to run 'git repack -a -d -f' after
a big import. This may take a while.

Support for Perforce integrations is still work in progress. Don't bother
trying it unless you want to hack on it :)


Incremental Imports
===================

After an initial import you can easily synchronize your git repository with
newer changes from the Perforce depot by just calling

  git-p4.p4 sync

in your git repository. git-p4 stores the depot path of the original import in
the .git/config file and remembers the last imported p4 revision as a git tag
called p4/<changenum> .

It is recommended to run 'git repack -a -d -f' from time to time when using
incremental imports to optimally combine the individual git packs that each
incremental import creates through the use of git-fast-import.

Submitting
==========

git-p4 has EXPERIMENTAL support for submitting changes from a git repository
back to a Perforce depot. This requires a Perforce checkout separate to your
git repository. This is the basic procedure:

    cd path/to/your/perforce/checkout
    git-p4.py submit --git-dir=/path/to/your/git/repository

This will create a temporary git branch, use git-rev-list to find out which git
commits are in your current branch but not in the "origin" branch. You can
override the name of the "origin" branch by using the --origin=mybranch option.
The "origin" branch has to be the branch populated with git-p4's sync
operation.

After some preparations (which might take a while) git-p4 enters a loop where
it will first show a Perforce submit template and a diff of the change to
apply.  After quitting the pager with 'q' git-p4 asks for confirmation for
issuing the "p4 submit" command and also gives you the option of editing the
submit template using "e".

If a submit fails you may have to "p4 resolve" and submit manually. You can
continue importing the remaining changes with

  git-p4.py submit --git-dir=/path/to/your/git/repository --continue

After submitting you should sync your origin branch from Perforce using
git-p4's sync command.