[PATCH v3 0/9] Introducing remote ODBs

This path series is a follow up from the patch series called "odb remote" that I sent earlier this year, which was itself a follow up from previous series. See the links section for more information.

As with the previous "odb remote" series, this series is only about integrating with the promisor/narrow clone work and showing that it makes it possible to use more than one promisor remote. Everything that is not necessary for that integration has been removed for now (though you can still find it in one of my branches on GitHub if you want).

There is one test in patch 8/9 that shows that more than one promisor remote can now be used, but I still feel that it could be interesting to add other such tests, so I am open to ideas in this area.

Changes compared to V2 of this patch series ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

  - fix unused variable in patch 2/9: the "SQUASH???" patch that Junio
    had created (thanks!) has been squashed

High level overview of this patch series ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

All the patches except 2/9 are unchanged compared to V2.

  - Patch 1/9:

This makes functions in fetch-object.c return an error code, which is necessary to later tell that they failed and try another remote odb when there is more than one. This could also just be seen as a fix to these functions.

  - Patch 2/9:

This introduces the minimum infrastructure for remote odbs.

  - Patches 3/9 and 4/9:

These patches implement remote_odb_get_direct() and remote_odb_get_many_direct() using the functions from fetch-object.c. These new functions will be used in following patches to replace the functions from fetch-object.c.

  - Patch 5/9:

This implement remote_odb_reinit() which will be needed to reparse the remote odb configuration.

  - Patches 6/9 and 7/9:

These patches integrate the remote odb mechanism into the promisor/narrow clone code. The "extensions.partialClone" config option is replaced by "odb.<name>.promisorRemote" and "core.partialCloneFilter" is replaced by "odb.<name>.partialCloneFilter".

  - Patch 8/9:

This adds a test case that shows that now more than one promisor remote can be used.

  - Patch 9/9:

This starts documenting the remote odb mechanism.

Discussion ~~~~~~~~~~

I am not sure that it is ok to completely replace the "extensions.partialclone" config option. Even if it is fully replaced, no "extensions.remoteodb" is implemented in these patches, as maybe the "extensions.partialclone" name could be kept even if the underlying mechanism is the remote odb mechanism.

Anyway I think that the remote odb mechanism is much more extensible, so I think using "extensions.partialclone" to specify a promisor remote should be at least deprecated.

Links ~~~~~

This patch series on GitHub:

V3: https://github.com/chriscool/git/commits/remote-odb
V2: https://github.com/chriscool/git/commits/remote-odb2
V1: https://github.com/chriscool/git/commits/remote-odb1

Discussions related to previous versions:

V2: https://public-inbox.org/git/20180630083542.20347-1-chriscool@tuxfamily.org/
V1: https://public-inbox.org/git/20180623121846.19750-1-chriscool@tuxfamily.org/

Previous "odb remote" series:

https://public-inbox.org/git/20180513103232.17514-1-chriscool@tuxfamily.org/ https://github.com/chriscool/git/commits/odb-remote

Version 1 and 2 of the "Promisor remotes and external ODB support" series:

https://public-inbox.org/git/20180103163403.11303-1-chriscool@tuxfamily.org/ https://public-inbox.org/git/20180319133147.15413-1-chriscool@tuxfamily.org/

Version 1 and 2 of the "Promisor remotes and external ODB support" series on GitHub:

https://github.com/chriscool/git/commits/gl-small-promisor-external-odb12 https://github.com/chriscool/git/commits/gl-small-promisor-external-odb71

Christian Couder (9):
  fetch-object: make functions return an error code
  Add initial remote odb support
  remote-odb: implement remote_odb_get_direct()
  remote-odb: implement remote_odb_get_many_direct()
  remote-odb: add remote_odb_reinit()
  Use remote_odb_get_direct() and has_remote_odb()
  Use odb.origin.partialclonefilter instead of core.partialclonefilter
  t0410: test fetching from many promisor remotes
  Documentation/config: add odb.<name>.promisorRemote

 Documentation/config.txt      |   5 ++
 Makefile                      |   2 +
 builtin/cat-file.c            |   5 +-
 builtin/fetch.c               |  13 ++--
 builtin/gc.c                  |   3 +-
 builtin/repack.c              |   3 +-
 cache.h                       |   2 -
 connected.c                   |   3 +-
 environment.c                 |   1 -
 fetch-object.c                |  15 ++--
 fetch-object.h                |   6 +-
 list-objects-filter-options.c |  51 +++++++------
 list-objects-filter-options.h |   3 +-
 odb-helper.c                  |  45 +++++++++++
 odb-helper.h                  |  24 ++++++
 packfile.c                    |   3 +-
 remote-odb.c                  | 137 ++++++++++++++++++++++++++++++++++
 remote-odb.h                  |  10 +++
 setup.c                       |   7 +-
 sha1-file.c                   |  14 ++--
 t/t0410-partial-clone.sh      |  58 +++++++++-----
 t/t5500-fetch-pack.sh         |   4 +-
 t/t5601-clone.sh              |   2 +-
 t/t5616-partial-clone.sh      |   4 +-
 t/t5702-protocol-v2.sh        |   2 +-
 unpack-trees.c                |   6 +-
 26 files changed, 342 insertions(+), 86 deletions(-)
 create mode 100644 odb-helper.c
 create mode 100644 odb-helper.h
 create mode 100644 remote-odb.c
 create mode 100644 remote-odb.h