hg: support for auto sharing stores when cloning
Many 3rd party consumers of Mercurial have created wrappers to
essentially perform clone+share as a single operation. This is
especially popular in automated processes like continuous integration
systems. The Jenkins CI software and Mozilla's Firefox release
automation infrastructure have both implemented custom code that
effectively perform clone+share. The common use case here is that
clients want to obtain N>1 checkouts while minimizing disk space and
network requirements. Furthermore, they often don't care that a clone
is an exact mirror of a remote: they are simply looking to obtain
checkouts of specific revisions.
When multiple third parties implement a similar feature, it's a good
sign that the feature is worth adding to the core product. This patch
adds support for an easy-to-use clone+share feature.
The internal "clone" function now accepts options to control auto
sharing during clone. When the auto share mode is active, a store will
be created/updated under the base directory specified and a new
repository pointing to the shared store will be created at the path
specified by the user.
The share extension has grown the ability to pass these options into
the clone command/function.
No command line options for this feature are added because we don't
feel the feature will be popular enough to warrant their existence.
There are two modes for auto share mode. In the default mode, the shared
repo is derived from the first changeset (rev 0) in the remote
repository. This enables related repositories existing at different URLs
to automatically use the same storage. In environments that operate
several repositories (separate repo for branch/head/bookmark or separate
repo per user), this has the potential to drastically reduce storage
and network requirements. In the other mode, the name is derived from the
remote's path/URL.
#require killdaemons
Preparing the subrepository 'sub'
$ hg init sub
$ echo sub > sub/sub
$ hg add -R sub
adding sub/sub (glob)
$ hg commit -R sub -m "sub import"
Preparing the 'main' repo which depends on the subrepo 'sub'
$ hg init main
$ echo main > main/main
$ echo "sub = ../sub" > main/.hgsub
$ hg clone sub main/sub
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg add -R main
adding main/.hgsub (glob)
adding main/main (glob)
$ hg commit -R main -m "main import"
Cleaning both repositories, just as a clone -U
$ hg up -C -R sub null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg up -C -R main null
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
$ rm -rf main/sub
hide outer repo
$ hg init
Serving them both using hgweb
$ printf '[paths]\n/main = main\nsub = sub\n' > webdir.conf
$ hg serve --webdir-conf webdir.conf -a localhost -p $HGPORT \
> -A /dev/null -E /dev/null --pid-file hg.pid -d
$ cat hg.pid >> $DAEMON_PIDS
Clone main from hgweb
$ hg clone "http://localhost:$HGPORT/main" cloned
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
updating to branch default
cloning subrepo sub from http://localhost:$HGPORT/sub
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
Checking cloned repo ids
$ hg id -R cloned
fdfeeb3e979e tip
$ hg id -R cloned/sub
863c1745b441 tip
subrepo debug for 'main' clone
$ hg debugsub -R cloned
path sub
source ../sub
revision 863c1745b441bd97a8c4a096e87793073f4fb215
$ killdaemons.py
subrepo paths with ssh urls
$ hg clone -e "python \"$TESTDIR/dummyssh\"" ssh://user@dummy/cloned sshclone
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
updating to branch default
cloning subrepo sub from ssh://user@dummy/sub
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg -R sshclone push -e "python \"$TESTDIR/dummyssh\"" ssh://user@dummy/`pwd`/cloned
pushing to ssh://user@dummy/$TESTTMP/cloned
pushing subrepo sub to ssh://user@dummy/$TESTTMP/sub
searching for changes
no changes found
searching for changes
no changes found
[1]
$ cat dummylog
Got arguments 1:user@dummy 2:hg -R cloned serve --stdio
Got arguments 1:user@dummy 2:hg -R sub serve --stdio
Got arguments 1:user@dummy 2:hg -R $TESTTMP/cloned serve --stdio
Got arguments 1:user@dummy 2:hg -R $TESTTMP/sub serve --stdio