[PATCH v3 7/8] repack: implement `--filter-to` for storing filtered out objects
- From
Christian Couder <christian.couder@gmail.com>
- Date
- Jul 24, 2023, 08:59 UTC
- Message-ID
- <20230724085909.3831831-8-christian.couder@gmail.com>
- In-Reply-To
- <20230724085909.3831831-1-christian.couder@gmail.com>
A previous commit has implemented `git repack --filter=<filter-spec>` to allow users to filter out some objects from the main pack and move them into a new different pack.
It would be nice if this new different pack could be created in a different directory than the regular pack. This would make it possible to move large blobs into a pack on a different kind of storage, for example cheaper storage.
Even in a different directory, this pack can be accessible if, for example, the Git alternates mechanism is used to point to it. In fact not using the Git alternates mechanism can corrupt a repo as the generated pack containing the filtered objects might not be accessible from the repo any more. So setting up the Git alternates mechanism should be done before using this feature if the user wants the repo to be fully usable while this feature is used.
In some cases, like when a repo has just been cloned or when there is no other activity in the repo, it's Ok to setup the Git alternates mechanism afterwards though. It's also Ok to just inspect the generated packfile containing the filtered objects and then just move it into the '.git/objects/pack/' directory manually. That's why it's not necessary for this command to check that the Git alternates mechanism has been already setup.
While at it, as an example to show that `--filter` and `--filter-to` work well with other options, let's also add a test to check that these options work well with `--max-pack-size`.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
repack: add test with --max-pack-size --- Documentation/git-repack.txt | 11 ++++++ builtin/repack.c | 11 +++++- t/t7700-repack.sh | 66 ++++++++++++++++++++++++++++++++++++ 3 files changed, 87 insertions(+), 1 deletion(-)
diff --git a/Documentation/git-repack.txt b/Documentation/git-repack.txt index 6d5bec7716..c0fbb0ed0c 100644 --- a/Documentation/git-repack.txt +++ b/Documentation/git-repack.txt @@ -155,6 +155,17 @@ depth is 4095. a single packfile containing all the objects. See linkgit:git-rev-list[1] for valid `<filter-spec>` forms. +--filter-to=<dir>:: + Write the pack containing filtered out objects to the + directory `<dir>`. Only useful with `--filter`. This can be + used for putting the pack on a separate object directory that + is accessed through the Git alternates mechanism. **WARNING:** + If the packfile containing the filtered out objects is not + accessible, the repo could be considered corrupt by Git as it + migh not be able to access the objects in that packfile. See + the `objects` and `objects/info/alternates` sections of + linkgit:gitrepository-layout[5]. + -b:: --write-bitmap-index:: Write a reachability bitmap index as part of the repack. This diff --git a/builtin/repack.c b/builtin/repack.c index 2c81b7738e..626284191b 100644 --- a/builtin/repack.c +++ b/builtin/repack.c @@ -871,6 +871,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix) int write_midx = 0; const char *cruft_expiration = NULL; const char *expire_to = NULL; + const char *filter_to = NULL; struct option builtin_repack_options[] = { OPT_BIT('a', NULL, &pack_everything, @@ -924,6 +925,8 @@ int cmd_repack(int argc, const char **argv, const char *prefix) N_("write a multi-pack index of the resulting packs")), OPT_STRING(0, "expire-to", &expire_to, N_("dir"), N_("pack prefix to store a pack containing pruned objects")), + OPT_STRING(0, "filter-to", &filter_to, N_("dir"), + N_("pack prefix to store a pack containing filtered out objects")), OPT_END() }; @@ -1067,6 +1070,9 @@ int cmd_repack(int argc, const char **argv, const char *prefix) strvec_push(&cmd.args, "--incremental"); } + if (filter_to && !po_args.filter) + die(_("option '%s' can only be used along with '%s'"), "--filter-to", "--filter"); + if (geometry) cmd.in = -1; else @@ -1154,8 +1160,11 @@ int cmd_repack(int argc, const char **argv, const char *prefix) } if (po_args.filter) { + if (!filter_to) + filter_to = packtmp; + ret = write_filtered_pack(&po_args, - packtmp, + filter_to, find_pack_prefix(), &names, &existing_nonkept_packs, diff --git a/t/t7700-repack.sh b/t/t7700-repack.sh index 0a2c73bca7..2bf237ba3a 100755 --- a/t/t7700-repack.sh +++ b/t/t7700-repack.sh @@ -351,6 +351,72 @@ test_expect_success '--filter fails with --write-bitmap-index' ' --filter=blob:none ' +test_expect_success '--filter-to stores filtered out objects' ' + git -C bare.git repack -a -d && + test_stdout_line_count = 1 ls bare.git/objects/pack/*.pack && + + git init --bare filtered.git && + git -C bare.git -c repack.writebitmaps=false repack -a -d \ + --filter=blob:none \ + --filter-to=../filtered.git/objects/pack/pack && + test_stdout_line_count = 1 ls bare.git/objects/pack/pack-*.pack && + test_stdout_line_count = 1 ls filtered.git/objects/pack/pack-*.pack && + + commit_pack=$(test-tool -C bare.git find-pack HEAD) && + test -n "$commit_pack" && + blob_pack=$(test-tool -C bare.git find-pack HEAD:file1) && + test -z "$blob_pack" && + blob_hash=$(git -C bare.git rev-parse HEAD:file1) && + test -n "$blob_hash" && + blob_pack=$(test-tool -C filtered.git find-pack $blob_hash) && + test -n "$blob_pack" && + + echo $(pwd)/filtered.git/objects >bare.git/objects/info/alternates && + blob_pack=$(test-tool -C bare.git find-pack HEAD:file1) && + test -n "$blob_pack" && + blob_content=$(git -C bare.git show $blob_hash) && + test "$blob_content" = "content1" +' + +test_expect_success '--filter works with --max-pack-size' ' + rm -rf filtered.git && + git init --bare filtered.git && + git init max-pack-size && + ( + cd max-pack-size && + test_commit base && + # two blobs which exceed the maximum pack size + test-tool genrandom foo 1048576 >foo && + git hash-object -w foo && + test-tool genrandom bar 1048576 >bar && + git hash-object -w bar && + git add foo bar && + git commit -m "adding foo and bar" + ) && + git clone --no-local --bare max-pack-size max-pack-size.git && + ( + cd max-pack-size.git && + git -c repack.writebitmaps=false repack -a -d --filter=blob:none \ + --max-pack-size=1M \ + --filter-to=../filtered.git/objects/pack/pack && + echo $(cd .. && pwd)/filtered.git/objects >objects/info/alternates && + + # Check that the 3 blobs are in different packfiles in filtered.git + test_stdout_line_count = 3 ls ../filtered.git/objects/pack/pack-*.pack && + test_stdout_line_count = 1 ls objects/pack/pack-*.pack && + foo_pack=$(test-tool find-pack HEAD:foo) && + bar_pack=$(test-tool find-pack HEAD:bar) && + base_pack=$(test-tool find-pack HEAD:base.t) && + test "$foo_pack" != "$bar_pack" && + test "$foo_pack" != "$base_pack" && + test "$bar_pack" != "$base_pack" && + for pack in "$foo_pack" "$bar_pack" "$base_pack" + do + case "$foo_pack" in */filtered.git/objects/pack/*) true ;; *) return 1 ;; esac + done + ) +' + objdir=.git/objects midx=$objdir/pack/multi-pack-index
-- 2.41.0.384.ged66511823