git/builtin
Jiang Xin 15d3af5e22 receive-pack: add new proc-receive hook
Git calls an internal `execute_commands` function to handle commands
sent from client to `git-receive-pack`.  Regardless of what references
the user pushes, git creates or updates the corresponding references if
the user has write-permission.  A contributor who has no
write-permission, cannot push to the repository directly.  So, the
contributor has to write commits to an alternate location, and sends
pull request by emails or by other ways.  We call this workflow as a
distributed workflow.

It would be more convenient to work in a centralized workflow like what
Gerrit provided for some cases.  For example, a read-only user who
cannot push to a branch directly can run the following `git push`
command to push commits to a pseudo reference (has a prefix "refs/for/",
not "refs/heads/") to create a code review.

    git push origin \
        HEAD:refs/for/<branch-name>/<session>

The `<branch-name>` in the above example can be as simple as "master",
or a more complicated branch name like "foo/bar".  The `<session>` in
the above example command can be the local branch name of the client
side, such as "my/topic".

We cannot implement a centralized workflow elegantly by using
"pre-receive" + "post-receive", because Git will call the internal
function "execute_commands" to create references (even the special
pseudo reference) between these two hooks.  Even though we can delete
the temporarily created pseudo reference via the "post-receive" hook,
having a temporary reference is not safe for concurrent pushes.

So, add a filter and a new handler to support this kind of workflow.
The filter will check the prefix of the reference name, and if the
command has a special reference name, the filter will turn a specific
field (`run_proc_receive`) on for the command.  Commands with this filed
turned on will be executed by a new handler (a hook named
"proc-receive") instead of the internal `execute_commands` function.
We can use this "proc-receive" command to create pull requests or send
emails for code review.

Suggested by Junio, this "proc-receive" hook reads the commands,
push-options (optional), and send result using a protocol in pkt-line
format.  In the following example, the letter "S" stands for
"receive-pack" and letter "H" stands for the hook.

    # Version and features negotiation.
    S: PKT-LINE(version=1\0push-options atomic...)
    S: flush-pkt
    H: PKT-LINE(version=1\0push-options...)
    H: flush-pkt

    # Send commands from server to the hook.
    S: PKT-LINE(<old-oid> <new-oid> <ref>)
    S: ... ...
    S: flush-pkt
    # Send push-options only if the 'push-options' feature is enabled.
    S: PKT-LINE(push-option)
    S: ... ...
    S: flush-pkt

    # Receive result from the hook.
    # OK, run this command successfully.
    H: PKT-LINE(ok <ref>)
    # NO, I reject it.
    H: PKT-LINE(ng <ref> <reason>)
    # Fall through, let 'receive-pack' to execute it.
    H: PKT-LINE(ok <ref>)
    H: PKT-LINE(option fall-through)
    # OK, but has an alternate reference.  The alternate reference name
    # and other status can be given in options
    H: PKT-LINE(ok <ref>)
    H: PKT-LINE(option refname <refname>)
    H: PKT-LINE(option old-oid <old-oid>)
    H: PKT-LINE(option new-oid <new-oid>)
    H: PKT-LINE(option forced-update)
    H: ... ...
    H: flush-pkt

After receiving a command, the hook will execute the command, and may
create/update different reference.  For example, a command for a pseudo
reference "refs/for/master/topic" may create/update different reference
such as "refs/pull/123/head".  The alternate reference name and other
status are given in option lines.

The list of commands returned from "proc-receive" will replace the
relevant commands that are sent from user to "receive-pack", and
"receive-pack" will continue to run the "execute_commands" function and
other routines.  Finally, the result of the execution of these commands
will be reported to end user.

The reporting function from "receive-pack" to "send-pack" will be
extended in latter commit just like what the "proc-receive" hook reports
to "receive-pack".

Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-27 12:47:47 -07:00
..
add.c Merge branch 'hw/advice-add-nothing' 2020-02-14 12:54:19 -08:00
am.c am: support --show-current-patch=diff to retrieve .git/rebase-apply/patch 2020-02-20 13:20:41 -08:00
annotate.c
apply.c
archive.c pack-protocol.txt: accept error packets in any context 2019-01-02 13:05:30 -08:00
bisect--helper.c bisect: libify check_good_are_ancestors_of_bad and its dependents 2020-02-19 09:37:14 -08:00
blame.c blame: use changed-path Bloom filters 2020-04-16 15:38:06 -07:00
branch.c l10n: minor case fix in 'git branch' '--unset-upstream' description 2019-12-09 12:30:55 -08:00
bundle.c bundle-verify: add --quiet 2019-11-11 11:46:29 +09:00
cat-file.c Merge branch 'jk/oid-array-cleanups' 2020-04-22 13:42:49 -07:00
check-attr.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
check-ignore.c check-ignore: fix documentation and implementation to match 2020-02-18 15:28:58 -08:00
check-mailmap.c
check-ref-format.c
checkout-index.c Merge branch 'nd/the-index-final' 2019-02-06 22:05:23 -08:00
checkout.c builtin/checkout: compute checkout metadata for checkouts 2020-03-16 11:37:02 -07:00
clean.c Merge branch 'en/fill-directory-exponential' 2020-04-29 16:15:31 -07:00
clone.c Merge branch 'jc/log-no-mailmap' 2020-04-28 15:50:00 -07:00
column.c builtin: consistently pass cmd_* prefix to parse_options 2019-05-13 14:22:53 +09:00
commit-graph.c Merge branch 'gs/commit-graph-path-filter' 2020-05-01 13:39:53 -07:00
commit-tree.c commit-tree: utilize parse-options api 2019-03-08 10:31:24 +09:00
commit.c Merge branch 'ds/blame-on-bloom' 2020-05-01 13:39:54 -07:00
config.c config: add '--show-scope' to print the scope of a config value 2020-02-10 10:49:12 -08:00
count-objects.c rename "alternate_object_database" to "object_directory" 2018-11-13 14:22:02 +09:00
credential.c
describe.c Merge branch 'jc/describe-misnamed-annotated-tag' 2020-03-26 17:11:21 -07:00
diff-files.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
diff-index.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
diff-tree.c diff-tree.c: load notes machinery when required 2020-04-20 18:22:54 -07:00
diff.c oid_array: rename source file from sha1-array 2020-03-30 10:59:08 -07:00
difftool.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
env--helper.c env--helper: mark a file-local symbol as static 2019-07-11 14:31:04 -07:00
fast-export.c Merge branch 'mt/use-passed-repo-more-in-funcs' 2020-02-14 12:54:22 -08:00
fetch-pack.c oid_array: rename source file from sha1-array 2020-03-30 10:59:08 -07:00
fetch.c Merge branch 'jt/connectivity-check-optim-in-partial-clone' 2020-04-22 13:42:43 -07:00
fmt-merge-msg.c Lib-ify fmt-merge-msg 2020-03-24 15:04:43 -07:00
for-each-ref.c parse_opt_ref_sorting: always use with NONEG flag 2019-03-21 12:03:35 +09:00
fsck.c fsck: only provide oid/type in fsck_error callback 2019-10-28 14:05:18 +09:00
gc.c commit-graph.h: store an odb in 'struct write_commit_graph_context' 2020-02-04 11:36:37 -08:00
get-tar-commit-id.c builtin/get-tar-commit-id: make hash size independent 2019-04-01 11:57:39 +09:00
grep.c Merge branch 'en/fill-directory-exponential' 2020-04-29 16:15:31 -07:00
hash-object.c builtin: consistently pass cmd_* prefix to parse_options 2019-05-13 14:22:53 +09:00
help.c Merge branch 'es/bugreport' 2020-05-01 13:39:59 -07:00
index-pack.c promisor-remote: accept 0 as oid_nr in function 2020-04-02 12:42:32 -07:00
init-db.c Merge branch 'bc/sha-256-part-1-of-4' 2020-03-26 17:11:20 -07:00
interpret-trailers.c interpret-trailers: load default config 2019-06-19 07:12:49 -07:00
log.c Merge branch 'ds/log-exclude-decoration-config' 2020-04-28 15:50:08 -07:00
ls-files.c Fix error-prone fill_directory() API; make it only return matches 2020-04-01 11:11:31 -07:00
ls-remote.c parse_opt_ref_sorting: always use with NONEG flag 2019-03-21 12:03:35 +09:00
ls-tree.c Merge branch 'nd/attr-pathspec-in-tree-walk' 2019-01-14 15:29:28 -08:00
mailinfo.c
mailsplit.c
merge-base.c rebase: --fork-point regression fix 2020-02-11 09:59:39 -08:00
merge-file.c assert NOARG/NONEG behavior of parse-options callbacks 2018-11-06 12:56:29 +09:00
merge-index.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
merge-ours.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
merge-recursive.c Ensure index matches head before invoking merge machinery, round N 2019-08-19 10:08:03 -07:00
merge-tree.c Merge branch 'jk/tree-walk-overflow' 2019-08-22 12:34:10 -07:00
merge.c Merge branch 'ds/blame-on-bloom' 2020-05-01 13:39:54 -07:00
mktag.c sha1-file: allow check_object_signature() to handle any repo 2020-01-31 10:45:39 -08:00
mktree.c mktree: drop unused length parameter 2019-05-13 14:22:54 +09:00
multi-pack-index.c multi-pack-index: add [--[no-]progress] option. 2019-10-23 12:05:06 +09:00
mv.c cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch 2019-01-24 11:55:06 -08:00
name-rev.c name-rev: sort tip names before applying 2020-02-05 10:36:33 -08:00
notes.c strbuf: add and use strbuf_insertstr() 2020-02-10 09:04:45 -08:00
pack-objects.c Merge branch 'jk/oid-array-cleanups' 2020-04-22 13:42:49 -07:00
pack-redundant.c object-store: rename and expand packed_git's sha1 member 2019-04-01 11:57:38 +09:00
pack-refs.c Honor core.precomposeUnicode in more places 2019-04-26 10:54:03 +09:00
patch-id.c patch-id: use oid_to_hex() to print multiple object IDs 2019-12-09 12:26:40 -08:00
prune-packed.c Lib-ify prune-packed 2020-03-24 15:04:44 -07:00
prune.c Lib-ify prune-packed 2020-03-24 15:04:44 -07:00
pull.c Merge branch 'dl/merge-autostash' 2020-04-29 16:15:27 -07:00
push.c push: anonymize URLs in error messages and warnings 2020-04-28 15:17:45 -07:00
range-diff.c range-diff: clear other_arg at end of function 2019-12-06 12:36:53 -08:00
read-tree.c sparse-checkout: update working directory in-process 2019-11-22 16:11:44 +09:00
rebase.c Merge branch 'en/rebase-root-and-fork-point-are-incompatible' 2020-05-01 13:39:58 -07:00
receive-pack.c receive-pack: add new proc-receive hook 2020-08-27 12:47:47 -07:00
reflog.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
remote-ext.c
remote-fd.c
remote.c remote rename/remove: gently handle remote.pushDefault config 2020-02-10 10:52:10 -08:00
repack.c Lib-ify prune-packed 2020-03-24 15:04:44 -07:00
replace.c sha1-file: pass git_hash_algo to hash_object_file() 2020-01-31 10:45:39 -08:00
rerere.c Merge branch 'nd/the-index' into md/list-objects-filter-by-depth 2019-01-15 15:38:29 -08:00
reset.c builtin/reset: compute checkout metadata for reset 2020-03-16 11:37:02 -07:00
rev-list.c rev-list --count: comment on the use of count_right++ 2020-02-18 13:21:46 -08:00
rev-parse.c get_superproject_working_tree(): return strbuf 2020-03-10 11:41:40 -07:00
revert.c Merge branch 'ra/cherry-pick-revert-skip' 2019-07-19 11:30:21 -07:00
rm.c rm: support the --pathspec-from-file option 2020-02-19 10:56:49 -08:00
send-pack.c oid_array: rename source file from sha1-array 2020-03-30 10:59:08 -07:00
shortlog.c Merge branch 'nd/show-gitcomp-compilation-fix' into maint 2018-12-15 12:24:33 +09:00
show-branch.c use strpbrk(3) to search for characters from a given set 2020-02-24 09:30:31 -08:00
show-index.c builtin/show-index: replace sha1_to_hex 2019-08-19 15:04:59 -07:00
show-ref.c Merge branch 'en/unicode-in-refnames' 2019-05-19 16:45:30 +09:00
sparse-checkout.c sparse-checkout: provide a new reapply subcommand 2020-03-27 11:33:31 -07:00
stash.c Merge branch 'en/fill-directory-exponential' 2020-04-29 16:15:31 -07:00
stripspace.c stripspace: allow -s/-c outside git repository 2018-12-26 15:41:47 -08:00
submodule--helper.c submodule--helper.c: Rename 'cb_foreach' to 'foreach_cb' 2020-03-18 12:43:25 -07:00
symbolic-ref.c
tag.c Merge branch 'jk/oid-array-cleanups' 2020-04-22 13:42:49 -07:00
unpack-file.c
unpack-objects.c sha1-file: pass git_hash_algo to hash_object_file() 2020-01-31 10:45:39 -08:00
update-index.c Merge branch 'js/update-index-ignore-removal-for-skip-worktree' 2019-11-10 18:02:16 +09:00
update-ref.c update-ref: implement interactive transaction handling 2020-04-02 11:09:49 -07:00
update-server-info.c
upload-archive.c archive: initialize archivers earlier 2018-10-26 10:17:59 +09:00
upload-pack.c builtin: consistently pass cmd_* prefix to parse_options 2019-05-13 14:22:53 +09:00
var.c
verify-commit.c Merge branch 'jk/no-system-includes-in-dot-c' 2019-07-31 14:38:56 -07:00
verify-pack.c
verify-tag.c verify-tag: drop signal.h include 2019-06-19 08:19:21 -07:00
worktree.c real_path: remove unsafe API 2020-03-10 11:41:40 -07:00
write-tree.c cmd_{read,write}_tree: rename "unused" variable that is used 2019-05-13 14:22:53 +09:00