| Message ID | 20240418184043.2900955-1-christian.couder@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | upload-pack: support a missing-action | expand |
Christian Couder <christian.couder@gmail.com> writes: > `git pack-objects` already supports a `--missing=<missing-action>` > option, so that it can avoid erroring out if some objects aren't > available. > > It is interesting to have `git upload-pack` support a similar way to > avoid sending some objects in case they aren't available on the > server. Is it interesting? In what way? > For example, in case both the server and the client are using a > separate promisor remote that contain some objects, it can be better > if the server doesn't try to send such objects back to the client, but > instead let the client get those objects separately from the promisor > remote. (The client needs to have the separate promisor remote > configured, for that to work.) It is unclear what the precondition for such an arrangement to work reliably, and a lot more importantly, how we can validate that the precondition holds when "fetch" talks to "upload-pack". If you get it wrong, you'd have a server that would corrupt repositories that fetch from it. That is where my "Is it really interesting? I do not find your explanation convincing yet." above primarily comes from. Presumably "fetch" could tell "upload-pack" something like: I know how to fetch missing objects from this and that promisor remotes, so if you choose to, you may omit objects that you know are available from these promisor remotes when sending objects to me. using a new capability, and we can allow upload-pack to omit objects only when such a new capability tells it to?
`git pack-objects` already supports a `--missing=<missing-action>` option, so that it can avoid erroring out if some objects aren't available. It is interesting to have `git upload-pack` support a similar way to avoid sending some objects in case they aren't available on the server. For example, in case both the server and the client are using a separate promisor remote that contain some objects, it can be better if the server doesn't try to send such objects back to the client, but instead let the client get those objects separately from the promisor remote. (The client needs to have the separate promisor remote configured, for that to work.) Another example could be a server where some objects have been corrupted or deleted. It could still be useful for clients who could get those objects from another source, like perhaps a different client, to be able to fetch or clone from the server. As `git rev-list` also supports a `--missing=<missing-action>` option, the first 3 patches in this series are about refactoring related code from both `git rev-list` and `git pack-objects` into new "missing.{c,h}" files. Patch 4/4 then adds a new `uploadpack.missingAction` configuration variable. Christian Couder (4): rev-list: refactor --missing=<missing-action> missing: support rejecting --missing=print pack-objects: use the missing action API upload-pack: allow configuring a missing-action Documentation/config/uploadpack.txt | 9 ++ Makefile | 1 + builtin/pack-objects.c | 46 +++++----- builtin/rev-list.c | 41 ++------- missing.c | 42 ++++++++++ missing.h | 20 +++++ t/t5706-upload-pack-missing.sh | 125 ++++++++++++++++++++++++++++ upload-pack.c | 19 +++++ 8 files changed, 244 insertions(+), 59 deletions(-) create mode 100644 missing.c create mode 100644 missing.h create mode 100755 t/t5706-upload-pack-missing.sh