This patch series is based on: 763fb763b8 (Merge branch 'jt/batch-fetch-blobs-in-diff' into jch, 2019-04-08) to avoid issues with jt/batch-fetch-blobs-in-diff. Introduction ~~~~~~~~~~~~ This path series is a follow up from the "remote odb" patch series that I sent last year, which were a follow up from previous series. See the links section for more information. The goal of this patch series is to make it possible to have and to fetch missing objects from multiple remotes instead of only one. For now the fetch order is the order of the remotes in the config, except for the remote specified by extensions.partialclone config option which comes last in the fetch order. I selected the name "Promisor remote" over "Partial clone remote" because it is shorter and because it is not only about cloning. The existing extensions.partialclone config option is respected, but it is not written in the config when a partial clone or fetch is made. Instead remote.<name>.promisor is set to "true". This may create a compatibility issue, but it makes it possible to start using many promisor remotes by just cloning and fetching from different remotes with partial clone filters. The compatibility issue could be resolved in a future iteration by just setting extensions.partialclone instead of remote.<name>.promisor the first time a promisor remote is used. The code might not work with many promisor remotes that don't all have all the promised objects, as that would require the fetch protocol to send packs with best effort, as described by Junio in: https://public-inbox.org/git/xmqqpnqve71d.fsf@xxxxxxxxxxxxxxxxxxxxxxxxx/ In general I have tried to change as few things as possible in the first patches of the series, though the last patches try to hide the old features that only made sense for the general code to use when there was only one promisor remote. High level view of new patches since the V4 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ There are 5 new patches in this series compared to V4. They are: - Patch 1/16 (t0410: remove pipes after git commands) This is a preparatory cleanup patch to improve t0410 as suggested by Szeder Gábor. - Patch 8/16 (diff: use promisor-remote.h instead of fetch-object.h) This patch applies to diff.c the same changes that are made in patch 7/11. They are in a separate patch because the changes need to be made only if the jt/batch-fetch-blobs-in-diff series is merged. So depending on what happens to jt/batch-fetch-blobs-in-diff, this patch can either be squashed into 7/11, be squashed in to jt/batch-fetch-blobs-in-diff, or be dropped. - Patch 14/16 (Remove fetch-object.{c,h} in favor of promisor-remote.{c,h}) - Patch 15/16 (Move repository_format_partial_clone to promisor-remote.c) - Patch 16/16 (Move core_partial_clone_filter_default to promisor-remote.c) These patches try to hide the old features (fetch_objects(), repository_format_partial_clone and core_partial_clone_filter_default) that only made sense for the general code to use when there was only one promisor remote. This ensures that there will be compilation errors rather than bugs or test failures if the old features are used in the old fashion way. High level view of other changes since the V4 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The title and purpose of the old patches didn't change, but the following changes were made: - Patch 3/16 (Add initial support for many promisor remotes) Remove check for "r->name" as "name" became a flex array in struct promisor_remote as suggested by Szeder Gábor and Junio. - Patch 4/16 (promisor-remote: implement promisor_remote_get_direct()) Added call to free() "missing" array. Added "struct object_id;" declaration in "promisor-remote.h". - Patch 6/16 (promisor-remote: use repository_format_partial_clone) Improved explanation about why the remote specified using the extensions.partialClone config option is tried last. - Patch 7/16 (Use promisor_remote_get_direct() and has_promisor_remote()) Remove now useless includes of "fetch-object.h" as suggested by Junio. - Patch 11/16 (t0410: test fetching from many promisor remotes) Improve tests as suggested by Szeder Gábor. - Patch 12/16 (partial-clone: add multiple remotes in the doc) Add explanation in the doc about why the remote specified using the extensions.partialClone config option is tried last as suggested by Junio. Other doc improvements. High level overview of old patches in this patch series ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - Patch 2/16 (fetch-object: make functions return an error code) This patch, makes functions in fetch-object.c return an error code, which is necessary to later tell that they failed and try another promisor remote when there is more than one. This could also just be seen as a fix to these functions. - Patch 3/16 (Add initial support for many promisor remotes) This introduces the minimum infrastructure for promisor remotes. - Patch 4/16 (promisor-remote: implement promisor_remote_get_direct()) - Patch 5/16 (promisor-remote: add promisor_remote_reinit()) - Patch 6/16 (promisor-remote: use repository_format_partial_clone) These patches add a few missing bits in the promisor remote infrastructure that will be needed in the following patches. - Patch 7/16 (Use promisor_remote_get_direct() and has_promisor_remote()) This replaces the previous interface that used only one promisor remote defined in extensions.partialclone with the new interface created by the previous patches. - Patch 9/16 (promisor-remote: parse remote.*.partialclonefilter) This replaces the way a partial clone filter was handled by a new way based on the previous patches that support more than one partial clone filter. - Patch 10/16 (builtin/fetch: remove unique promisor remote limitation) This patch removes the limitation in builtin/fetch.c to have only one promisor remote. - Patch 12/16 (t0410: test fetching from many promisor remotes) This adds test cases that shows that now more than one promisor remote can be used and that remote.<name>.promisor is set to "true" when fetching from a new promisor remote. - Patch 13/16 (partial-clone: add multiple remotes in the doc) - Patch 14/16 (remote: add promisor and partial clone config to the doc) These documentation patches explain how things can work with more than one promisor remote. Links ~~~~~ This patch series on GitHub: V5: https://github.com/chriscool/git/commits/many-promisor-remotes V4: https://github.com/chriscool/git/commits/many-promisor-remotes58 V3: https://github.com/chriscool/git/commits/many-promisor-remotes40 V2: https://github.com/chriscool/git/commits/many-promisor-remotes35 V1: https://github.com/chriscool/git/commits/many-promisor-remotes17 On the mailing list: V4: https://public-inbox.org/git/20190401164045.17328-1-chriscool@xxxxxxxxxxxxx/ V3: https://public-inbox.org/git/20190312132959.11764-1-chriscool@xxxxxxxxxxxxx/ V2: https://public-inbox.org/git/20190122144212.15119-1-chriscool@xxxxxxxxxxxxx/ V1: https://public-inbox.org/git/20181211052746.16218-1-chriscool@xxxxxxxxxxxxx/ This patch series is a follow up from the discussions related to the remote odb V4 patch series: https://public-inbox.org/git/20180802061505.2983-1-chriscool@xxxxxxxxxxxxx/ Especially in: https://public-inbox.org/git/CAP8UFD3nrhjANwNDqTwx5ZtnZNcnbAFqUN=u=LrvzuH4+3wQQA@xxxxxxxxxxxxxx/ I said that I would like to work on things in the following order: 1) Teaching partial clone to attempt to fetch missing objects from multiple remotes instead of only one using the order in the config. 2) Simplifying the protocol for fetching missing objects so that it can be satisfied by a lighter weight object storage system than a full Git server. 3) Making it possible to explicitly define an order in which the remotes are accessed. 4) Making the criteria for what objects can be missing more aggressive, so that I can "git add" a large file and work with it using Git without even having a second copy of that object in my local object store. And this patch series is about the 1). The previous remote odb patch series on GitHub: V5: https://github.com/chriscool/git/commits/remote-odb V4: https://github.com/chriscool/git/commits/remote-odb5 V3: https://github.com/chriscool/git/commits/remote-odb3 V2: https://github.com/chriscool/git/commits/remote-odb2 V1: https://github.com/chriscool/git/commits/remote-odb1 Discussions related to previous versions of the odb patch series: V4: https://public-inbox.org/git/20180802061505.2983-1-chriscool@xxxxxxxxxxxxx/ V3: https://public-inbox.org/git/20180713174959.16748-1-chriscool@xxxxxxxxxxxxx/ V2: https://public-inbox.org/git/20180630083542.20347-1-chriscool@xxxxxxxxxxxxx/ V1: https://public-inbox.org/git/20180623121846.19750-1-chriscool@xxxxxxxxxxxxx/ Christian Couder (16): t0410: remove pipes after git commands fetch-object: make functions return an error code Add initial support for many promisor remotes promisor-remote: implement promisor_remote_get_direct() promisor-remote: add promisor_remote_reinit() promisor-remote: use repository_format_partial_clone Use promisor_remote_get_direct() and has_promisor_remote() diff: use promisor-remote.h instead of fetch-object.h promisor-remote: parse remote.*.partialclonefilter builtin/fetch: remove unique promisor remote limitation t0410: test fetching from many promisor remotes partial-clone: add multiple remotes in the doc remote: add promisor and partial clone config to the doc Remove fetch-object.{c,h} in favor of promisor-remote.{c,h} Move repository_format_partial_clone to promisor-remote.c Move core_partial_clone_filter_default to promisor-remote.c Documentation/config/remote.txt | 8 + Documentation/technical/partial-clone.txt | 117 +++++++--- Makefile | 2 +- builtin/cat-file.c | 5 +- builtin/fetch.c | 29 +-- builtin/gc.c | 3 +- builtin/repack.c | 3 +- cache-tree.c | 3 +- cache.h | 2 - config.c | 5 - connected.c | 3 +- diff.c | 8 +- environment.c | 2 - fetch-object.c | 40 ---- fetch-object.h | 9 - list-objects-filter-options.c | 51 +++-- list-objects-filter-options.h | 3 +- packfile.c | 3 +- promisor-remote.c | 264 ++++++++++++++++++++++ promisor-remote.h | 29 +++ setup.c | 3 +- sha1-file.c | 15 +- t/t0410-partial-clone.sh | 61 ++++- t/t5601-clone.sh | 3 +- t/t5616-partial-clone.sh | 4 +- unpack-trees.c | 7 +- 26 files changed, 514 insertions(+), 168 deletions(-) delete mode 100644 fetch-object.c delete mode 100644 fetch-object.h create mode 100644 promisor-remote.c create mode 100644 promisor-remote.h -- 2.21.0.750.g68c8ebb2ac
