From: Emily Shaffer <emilyshaffer@xxxxxxxxxx> Teach the hook.[hc] library to parse configs to populate the list of hooks to run for a given event. Multiple commands can be specified for a given hook by providing multiple "hook.<friendly-name>.command = <path-to-hook>" and "hook.<friendly-name>.event = <hook-event>" lines. Hooks will be started in config order of the "hook.<name>.event" lines (but may run in parallel). For example: $ git config --get-regexp "^hook\." hook.bar.command=~/bar.sh hook.bar.event=pre-commit # Will run ~/bar.sh, then .git/hooks/pre-commit $ git hook run pre-commit Signed-off-by: Emily Shaffer <emilyshaffer@xxxxxxxxxx> --- Documentation/config/hook.txt | 18 ++++ Documentation/git-hook.txt | 135 +++++++++++++++++++++++++++- builtin/hook.c | 3 +- hook.c | 161 +++++++++++++++++++++++++++++---- hook.h | 7 +- t/t1800-hook.sh | 164 +++++++++++++++++++++++++++++++++- 6 files changed, 465 insertions(+), 23 deletions(-) diff --git a/Documentation/config/hook.txt b/Documentation/config/hook.txt index 96d3d6572c1..c3947563280 100644 --- a/Documentation/config/hook.txt +++ b/Documentation/config/hook.txt @@ -1,3 +1,21 @@ +hook.<name>.command:: + A command to execute whenever `hook.<name>` is invoked. `<name>` should + be a unique "friendly" name which you can use to identify this hook + command. (You can specify when to invoke this command with + `hook.<name>.event`.) The value can be an executable on your device or a + oneliner for your shell. If more than one value is specified for the + same `<name>`, the last value parsed will be the only command executed. + See linkgit:git-hook[1]. + +hook.<name>.event:: + The hook events which should invoke `hook.<name>`. `<name>` should be a + unique "friendly" name which you can use to identify this hook. The + value should be the name of a hook event, like "pre-commit" or "update". + (See linkgit:githooks[5] for a complete list of hooks Git knows about.) + On the specified event, the associated `hook.<name>.command` will be + executed. More than one event can be specified if you wish for + `hook.<name>` to execute on multiple events. See linkgit:git-hook[1]. + hook.jobs:: Specifies how many hooks can be run simultaneously during parallelized hook execution. If unspecified, defaults to the number of processors on diff --git a/Documentation/git-hook.txt b/Documentation/git-hook.txt index 88588b38143..51bda42fb83 100644 --- a/Documentation/git-hook.txt +++ b/Documentation/git-hook.txt @@ -19,12 +19,102 @@ This command is an interface to git hooks (see linkgit:githooks[5]). Currently it only provides a convenience wrapper for running hooks for use by git itself. In the future it might gain other functionality. +It's possible to use this command to refer to hooks which are not native to Git, +for example if a wrapper around Git wishes to expose hooks into its own +operation in a way which is already familiar to Git users. However, wrappers +invoking such hooks should be careful to name their hook events something which +Git is unlikely to use for a native hook later on. For example, Git is much less +likely to create a `mytool-validate-commit` hook than it is to create a +`validate-commit` hook. + +This command parses the default configuration files for sets of configs like +so: + + [hook "linter"] + event = pre-commit + command = ~/bin/linter --cpp20 + +In this example, `[hook "linter"]` represents one script - `~/bin/linter +--cpp20` - which can be shared by many repos, and even by many hook events, if +appropriate. + +To add an unrelated hook which runs on a different event, for example a +spell-checker for your commit messages, you would write a configuration like so: + + [hook "linter"] + event = pre-commit + command = ~/bin/linter --cpp20 + [hook "spellcheck"] + event = commit-msg + command = ~/bin/spellchecker + +With this config, when you run 'git commit', first `~/bin/linter --cpp20` will +have a chance to check your files to be committed (during the `pre-commit` hook +event`), and then `~/bin/spellchecker` will have a chance to check your commit +message (during the `commit-msg` hook event). + +Commands are run in the order Git encounters their associated +`hook.<name>.event` configs during the configuration parse (see +linkgit:git-config[1]). Although multiple `hook.linter.event` configs can be +added, only one `hook.linter.command` event is valid - Git uses "last-one-wins" +to determine which command to run. + +So if you wanted your linter to run when you commit as well as when you push, +you would configure it like so: + + [hook "linter"] + event = pre-commit + event = pre-push + command = ~/bin/linter --cpp20 + +With this config, `~/bin/linter --cpp20` would be run by Git before a commit is +generated (during `pre-commit`) as well as before a push is performed (during +`pre-push`). + +And if you wanted to run your linter as well as a secret-leak detector during +only the "pre-commit" hook event, you would configure it instead like so: + + [hook "linter"] + event = pre-commit + command = ~/bin/linter --cpp20 + [hook "no-leaks"] + event = pre-commit + command = ~/bin/leak-detector + +With this config, before a commit is generated (during `pre-commit`), Git would +first start `~/bin/linter --cpp20` and second start `~/bin/leak-detector`. It +would evaluate the output of each when deciding whether to proceed with the +commit. + +For a full list of hook events which you can set your `hook.<name>.event` to, +and how hooks are invoked during those events, see linkgit:githooks[5]. + +Git will ignore any `hook.<name>.event` that specifies an event it doesn't +recognize. This is intended so that tools which wrap Git can use the hook +infrastructure to run their own hooks; see <<WRAPPERS>> for more guidance. + +In general, when instructions suggest adding a script to +`.git/hooks/<hook-event>`, you can specify it in the config instead by running: + +---- +git config hook.<some-name>.command <path-to-script> +git config --add hook.<some-name>.event <hook-event> +---- + +This way you can share the script between multiple repos. That is, `cp +~/my-script.sh ~/project/.git/hooks/pre-commit` would become: + +---- +git config hook.my-script.command ~/my-script.sh +git config --add hook.my-script.event pre-commit +---- + SUBCOMMANDS ----------- run:: - Run the `<hook-name>` hook. See linkgit:githooks[5] for - the hook names we support. + Runs hooks configured for `<hook-name>`, in the order they are + discovered during the config parse. + Any positional arguments to the hook should be passed after an optional `--` (or `--end-of-options`, see linkgit:gitcli[7]). The @@ -58,6 +148,47 @@ config is not specified, uses the number of CPUs on the current system. Some hooks may be ineligible for parallelization: for example, 'commit-msg' intends hooks modify the commit message body and cannot be parallelized. +[[WRAPPERS]] +WRAPPERS +-------- + +`git hook run` has been designed to make it easy for tools which wrap Git to +configure and execute hooks using the Git hook infrastructure. It is possible to +provide arguments, environment variables (TODO this is missing from reroll TODO), +and stdin via the command line, as well as specifying parallel or series +execution if the user has provided multiple hooks. + +Assuming your wrapper wants to support a hook named "mywrapper-start-tests", you +can have your users specify their hooks like so: + + [hook "setup-test-dashboard"] + event = mywrapper-start-tests + command = ~/mywrapper/setup-dashboard.py --tap + +Then, in your 'mywrapper' tool, you can invoke any users' configured hooks by +running: + +---- +git hook run mywrapper-start-tests \ + # providing something to stdin + --stdin some-tempfile-123 \ + # setting an env var (TODO THIS IS MISSING TODO) + --env MYWRAPPER_EXECUTION_MODE=foo \ + # execute hooks in serial + --jobs 1 \ + # plus some arguments of your own... + -- \ + --testname bar \ + baz +---- + +Take care to name your wrapper's hook events in a way which is unlikely to +overlap with Git's native hooks (see linkgit:githooks[5]) - a hook event named +`mywrappertool-validate-commit` is much less likely to be added to native Git +than a hook event named `validate-commit`. If Git begins to use a hook event +named the same thing as your wrapper hook, it may invoke your users' hooks in +unintended and unsupported ways. + CONFIGURATION ------------- include::config/hook.txt[] diff --git a/builtin/hook.c b/builtin/hook.c index 1e6b15d565a..bb8fdde6bad 100644 --- a/builtin/hook.c +++ b/builtin/hook.c @@ -61,7 +61,8 @@ static int list(int argc, const char **argv, const char *prefix) struct hook *item = list_entry(pos, struct hook, list); item = list_entry(pos, struct hook, list); if (item) - printf("%s\n", item->hook_path); + printf("%s\n", item->name ? item->name + : _("hook from hookdir")); } cleanup: diff --git a/hook.c b/hook.c index 600030c59ec..b825fa7c7ae 100644 --- a/hook.c +++ b/hook.c @@ -8,10 +8,54 @@ static void free_hook(struct hook *ptr) if (!ptr) return; + free(ptr->name); free(ptr->feed_pipe_cb_data); free(ptr); } +/* + * Walks the linked list at 'head' to check if any hook named 'name' + * already exists. Returns a pointer to that hook if so, otherwise returns NULL. + */ +static struct hook *find_hook_by_name(struct list_head *head, + const char *name) +{ + struct list_head *pos = NULL, *tmp = NULL; + struct hook *found = NULL; + + list_for_each_safe(pos, tmp, head) { + struct hook *it = list_entry(pos, struct hook, list); + if (!strcmp(it->name, name)) { + list_del(pos); + found = it; + break; + } + } + return found; +} + +/* + * Adds a hook if it's not already in the list, or moves it to the tail of the + * list if it was already there. name == NULL indicates it's from the hookdir; + * just append it in this case. + */ +static void append_or_move_hook(struct list_head *head, const char *name) +{ + struct hook *to_add = NULL; + + /* if it's not from hookdir, check if the hook is already in the list */ + if (name) + to_add = find_hook_by_name(head, name); + + if (!to_add) { + /* adding a new hook, not moving an old one */ + to_add = xcalloc(1, sizeof(*to_add)); + to_add->name = xstrdup_or_null(name); + } + + list_add_tail(&to_add->list, head); +} + static void remove_hook(struct list_head *to_remove) { struct hook *hook_to_remove = list_entry(to_remove, struct hook, list); @@ -73,26 +117,72 @@ int hook_exists(const char *name) return exists; } +struct hook_config_cb +{ + const char *hook_event; + struct list_head *list; +}; + +/* + * Callback for git_config which adds configured hooks to a hook list. Hooks + * can be configured by specifying both hook.<friend-name>.command = <path> and + * hook.<friendly-name>.event = <hook-event>. + */ +static int hook_config_lookup(const char *key, const char *value, void *cb_data) +{ + struct hook_config_cb *data = cb_data; + const char *subsection, *parsed_key; + size_t subsection_len = 0; + struct strbuf subsection_cpy = STRBUF_INIT; + + /* + * Don't bother doing the expensive parse if there's no + * chance that the config matches 'hook.myhook.event = hook_event'. + */ + if (!value || strcmp(value, data->hook_event)) + return 0; + + /* Looking for "hook.friendlyname.event = hook_event" */ + if (parse_config_key(key, + "hook", + &subsection, + &subsection_len, + &parsed_key) || + strcmp(parsed_key, "event")) + return 0; + + /* + * 'subsection' is a pointer to the internals of 'key', which we don't + * own the memory for. Copy it away to the hook list. + */ + strbuf_add(&subsection_cpy, subsection, subsection_len); + + append_or_move_hook(data->list, subsection_cpy.buf); + strbuf_release(&subsection_cpy); + + return 0; +} + struct list_head *list_hooks(const char *hookname) { struct list_head *hook_head = xmalloc(sizeof(struct list_head)); + struct hook_config_cb cb_data = { + .hook_event = hookname, + .list = hook_head, + }; INIT_LIST_HEAD(hook_head); if (!hookname) BUG("null hookname was provided to hook_list()!"); - if (have_git_dir()) { - const char *hook_path = find_hook(hookname); + /* Add the hooks from the config, e.g. hook.myhook.event = pre-commit */ + git_config(hook_config_lookup, &cb_data); - /* Add the hook from the hookdir */ - if (hook_path) { - struct hook *to_add = xmalloc(sizeof(*to_add)); - to_add->hook_path = hook_path; - to_add->feed_pipe_cb_data = NULL; - list_add_tail(&to_add->list, hook_head); - } - } + /* Add the hook from the hookdir. The placeholder makes it easier to + * allocate work in pick_next_hook. */ + if (find_hook(hookname)) + append_or_move_hook(hook_head, NULL); return hook_head; } @@ -153,11 +243,47 @@ static int pick_next_hook(struct child_process *cp, cp->trace2_hook_name = hook_cb->hook_name; cp->dir = hook_cb->options->dir; + /* + * to enable oneliners, let config-specified hooks run in shell. + * config-specified hooks have a name. + */ + cp->use_shell = !!run_me->name; + /* add command */ - if (hook_cb->options->absolute_path) - strvec_push(&cp->args, absolute_path(run_me->hook_path)); - else - strvec_push(&cp->args, run_me->hook_path); + if (run_me->name) { + /* ...from config */ + struct strbuf cmd_key = STRBUF_INIT; + char *command = NULL; + + strbuf_addf(&cmd_key, "hook.%s.command", run_me->name); + if (git_config_get_string(cmd_key.buf, &command)) { + /* TODO test me! */ + die(_("'hook.%s.command' must be configured " + "or 'hook.%s.event' must be removed; aborting.\n"), + run_me->name, run_me->name); + } + + strvec_push(&cp->args, command); + free(command); + strbuf_release(&cmd_key); + } else { + /* ...from hookdir. */ + const char *hook_path = NULL; + /* + * At this point we are already running, so don't validate + * whether the hook name is known or not. Validation was + * performed earlier in list_hooks(). + */ + hook_path = find_hook(hook_cb->hook_name); + if (!hook_path) + BUG("hookdir hook in hook list but no hookdir hook present in filesystem"); + + if (hook_cb->options->absolute_path) + hook_path = absolute_path(hook_path); + + strvec_push(&cp->args, hook_path); + } + /* * add passed-in argv, without expanding - let the user get back @@ -187,8 +313,11 @@ static int notify_start_failure(struct strbuf *out, hook_cb->rc |= 1; - strbuf_addf(out, _("Couldn't start hook '%s'\n"), - attempted->hook_path); + if (attempted->name) + strbuf_addf(out, _("Couldn't start hook '%s'\n"), + attempted->name); + else + strbuf_addstr(out, _("Couldn't start hook from hooks directory\n")); return 1; } diff --git a/hook.h b/hook.h index fe16ab35028..4b728991089 100644 --- a/hook.h +++ b/hook.h @@ -7,8 +7,11 @@ struct hook { struct list_head list; - /* The path to the hook */ - const char *hook_path; + /* + * The friendly name of the hook. NULL indicates the hook is from the + * hookdir. + */ + char *name; /* * Use this to keep state for your feed_pipe_fn if you are using diff --git a/t/t1800-hook.sh b/t/t1800-hook.sh index 7a1dae4e95e..68e7ff7de7e 100755 --- a/t/t1800-hook.sh +++ b/t/t1800-hook.sh @@ -1,13 +1,30 @@ #!/bin/sh -test_description='git-hook command' +test_description='git-hook command and config-managed multihooks' . ./test-lib.sh +setup_hooks () { + test_config hook.ghi.command "/path/ghi" + test_config hook.ghi.event pre-commit --add + test_config hook.ghi.event test-hook --add + test_config_global hook.def.command "/path/def" + test_config_global hook.def.event pre-commit --add +} + +setup_hookdir () { + mkdir .git/hooks + write_script .git/hooks/pre-commit <<-EOF + echo \"Legacy Hook\" + EOF + test_when_finished rm -rf .git/hooks +} + test_expect_success 'git hook usage' ' test_expect_code 129 git hook && test_expect_code 129 git hook run && test_expect_code 129 git hook run -h && + test_expect_code 129 git hook list -h && test_expect_code 129 git hook run --unknown 2>err && test_expect_code 129 git hook list && test_expect_code 129 git hook list -h && @@ -105,7 +122,7 @@ test_expect_success 'git hook list: does-not-exist hook' ' test_expect_success 'git hook list: existing hook' ' cat >expect <<-\EOF && - .git/hooks/test-hook + hook from hookdir EOF git hook list test-hook >actual && test_cmp expect actual @@ -162,4 +179,147 @@ test_expect_success 'stdin to hooks' ' test_cmp expect actual ' +test_expect_success 'git hook list orders by config order' ' + setup_hooks && + + cat >expected <<-\EOF && + def + ghi + EOF + + git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'git hook list reorders on duplicate event declarations' ' + setup_hooks && + + # 'def' is usually configured globally; move it to the end by + # configuring it locally. + test_config hook.def.event "pre-commit" --add && + + cat >expected <<-\EOF && + ghi + def + EOF + + git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'hook can be configured for multiple events' ' + setup_hooks && + + # 'ghi' should be included in both 'pre-commit' and 'test-hook' + git hook list pre-commit >actual && + grep "ghi" actual && + git hook list test-hook >actual && + grep "ghi" actual +' + +test_expect_success 'git hook list shows hooks from the hookdir' ' + setup_hookdir && + + cat >expected <<-\EOF && + hook from hookdir + EOF + + git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'inline hook definitions execute oneliners' ' + test_config hook.oneliner.event "pre-commit" && + test_config hook.oneliner.command "echo \"Hello World\"" && + + echo "Hello World" >expected && + + # hooks are run with stdout_to_stderr = 1 + git hook run pre-commit 2>actual && + test_cmp expected actual +' + +test_expect_success 'inline hook definitions resolve paths' ' + write_script sample-hook.sh <<-\EOF && + echo \"Sample Hook\" + EOF + + test_when_finished "rm sample-hook.sh" && + + test_config hook.sample-hook.event pre-commit && + test_config hook.sample-hook.command "\"$(pwd)/sample-hook.sh\"" && + + echo \"Sample Hook\" >expected && + + # hooks are run with stdout_to_stderr = 1 + git hook run pre-commit 2>actual && + test_cmp expected actual +' + +test_expect_success 'hookdir hook included in git hook run' ' + setup_hookdir && + + echo \"Legacy Hook\" >expected && + + # hooks are run with stdout_to_stderr = 1 + git hook run pre-commit 2>actual && + test_cmp expected actual +' + +test_expect_success 'stdin to multiple hooks' ' + test_config hook.stdin-a.event "test-hook" --add && + test_config hook.stdin-a.command "xargs -P1 -I% echo a%" --add && + test_config hook.stdin-b.event "test-hook" --add && + test_config hook.stdin-b.command "xargs -P1 -I% echo b%" --add && + + cat >input <<-\EOF && + 1 + 2 + 3 + EOF + + cat >expected <<-\EOF && + a1 + a2 + a3 + b1 + b2 + b3 + EOF + + git hook run --to-stdin=input test-hook 2>actual && + test_cmp expected actual +' + +test_expect_success 'multiple hooks in series' ' + test_config hook.series-1.event "test-hook" && + test_config hook.series-1.command "echo 1" --add && + test_config hook.series-2.event "test-hook" && + test_config hook.series-2.command "echo 2" --add && + mkdir .git/hooks && + write_script .git/hooks/test-hook <<-EOF && + echo 3 + EOF + + cat >expected <<-\EOF && + 1 + 2 + 3 + EOF + + git hook run -j1 test-hook 2>actual && + test_cmp expected actual && + + rm -rf .git/hooks +' + +test_expect_success 'rejects hooks with no commands configured' ' + test_config hook.broken.event "test-hook" && + + echo broken >expected && + git hook list test-hook >actual && + test_cmp expected actual && + test_must_fail git hook run test-hook +' + test_done -- 2.33.0.867.g88ec4638586