问题
A couple of years ago, a subfolder in one of my Perforce depots (e.g. //FirstDepot/LargeSubfolder/...) became too large to maintain, so I 'migrated' it into a depot of its own (e.g. //NewDepotFromLargeSubfolder/...). Perforce does not support integrations from one depot to another, so I basically checked out the files, added them to the new depot and deleted them from the subfolder.
Now I am about to migrate the entire Perforce server to a number of git repositories. The git p4 procedure works very well, I already migrated other, unrelated Perforce depots to git successfully (including their full file history using @all - but then, those depots were never 'migrated' within Perforce in the way described...).
The problem is that I do not want to lose the file history underneath //FirstDepot/LargeSubfolder/.... There are a couple thousand changelists in there (plus a couple thousand more at //NewDepotFromLargeSubfolder/...) and many of them contain very valuable information.
I tried to migrate the file history from the first location and then 'stack' the history of the second location on top of it:
host:~ user$ mkdir SomeTempFolder
host:~ user$ cd SomeTempFolder
host:SomeTempFolder user$ export P4PORT=perforce:1666
host:SomeTempFolder user$ git p4 clone //FirstDepot/LargeSubfolder@all gitRepoFolder
Importing from //FirstDepot/LargeSubfolder@all into gitRepoFolder
Initialized empty Git repository in /Users/user/SomeTempFolder/gitRepoFolder/.git/
Import destination: refs/remotes/p4/master
Importing revision 26776 (99%)
Ignoring apple filetype file //FirstDepot/LargeSubfolder/SomePath/SomeIconFile.icns
Importing revision 26778 (100%)
So apart from a message about a Mac OS X icon file being ignored, the first bit works. The second part fails however:
host:SomeTempFolder user$ git p4 clone //NewDepotFromLargeSubfolder@all gitRepoFolder
Importing from //NewDepotFromLargeSubfolder@all into gitRepoFolder
Reinitialized existing Git repository in /Users/user/SomeTempFolder/gitRepoFolder/.git/
Import destination: refs/remotes/p4/master
Importing revision 26777 (0%)
Ignoring apple filetype file //NewDepotFromLargeSubfolder/SomePath/SomeIconFile.icns
Importing revision 27142 (33%)
Ignoring apple filetype file //NewDepotFromLargeSubfolder/AnotherPath/Some AppleScript file.scpt
Ignoring apple filetype file //NewDepotFromLargeSubfolder/AnotherPath/Another AppleScript file.scpt
Importing revision 27620 (100%)
fast-import failed: warning: Not updating refs/remotes/p4/master (new tip <some long git ID> does not contain <another long git ID>)
git-fast-import statistics:
<loads of git statistic>
Running git p4 with --verbose seems to indicate that the actual importing of Perforce revisions completes successfully, but then something goes wrong which I don't understand:
Importing revision 27620 (100%)commit into refs/remotes/p4/master
Opening pipe: ['p4', '-G', '-x', '-', 'print']
Path/of/the/file/in/the/last/Changelist
Reading pipe: ['git', 'config', '--bool', 'git-p4.importLabels']
Traceback (most recent call last):
File "/usr/libexec/git-core/git-p4", line 3287, in <module>
main()
File "/usr/libexec/git-core/git-p4", line 3281, in main
if not cmd.run(args):
File "/usr/libexec/git-core/git-p4", line 3155, in run
if not P4Sync.run(self, depotPaths):
File "/usr/libexec/git-core/git-p4", line 3030, in run
die("fast-import failed: %s" % self.gitError.read())
File "/usr/libexec/git-core/git-p4", line 106, in die
raise Exception(msg)
Exception: fast-import failed: warning: ... (as above) ...
The migration of the second part works fine when done into a new git repository.
After reading `git-p4 clone` fails "new tip ... does not contain ...", I retried the migration in a working folder without spaces; same result. I'm working on Mac OS X btw, but the Perforce server is running on a Debian 7.5 virtual machine.
My questions:
+ Does anyone have some advice how to find out what's wrong here ?
+ Is it generally possible to 'stack' chunks of revision history ?
+ Can anyone think of an alternate approach (apart from having two git repos) ?
I'm not a git expert at all, but so far, I could pretty much just throw stuff at it and git did an excellent job of figuring out what I want to do; also the Reinitialized existing Git repository message seems to indicate that I'm not totally off.
回答1:
The migration of the second part works fine when done into a new git repository
That could be the basis of an acceptable workaround here: have to separate Git repo, and chose a technique from "How do you merge two git repositories?" to get one final repo.
The git filter-branch approach is detailed in "Combining multiple git repositories".
(You also have a simpler approach based on merge, also described here: The OP ssc selected "Merge two Git repositories without breaking file history")
来源：https://stackoverflow.com/questions/28127479/git-p4-migrate-full-history-including-integration-history