Re: [PATCH v9 2/2] send-email: expose header information to git-send-email's sendemail-validate hook

> On 2023-01-19 20:24, Michael Strawbridge wrote:
>> To allow further flexibility in the Git hook, the SMTP header
>> information of the email which git-send-email intends to send, is now
>> passed as the 2nd argument to the sendemail-validate hook.
>>
>> As an example, this can be useful for acting upon keywords in the
>> subject or specific email addresses.
>>
>> Cc: Luben Tuikov <luben.tuikov@amd.com>
>> Cc: Junio C Hamano <gitster@pobox.com>
>> Cc: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
>> Acked-by: Luben Tuikov <luben.tuikov@amd.com>
>> Signed-off-by: Michael Strawbridge <michael.strawbridge@amd.com>
>> ---
>>  Documentation/githooks.txt | 27 ++++++++++++++++++----
>>  git-send-email.perl        | 46 ++++++++++++++++++++++----------------
>>  t/t9001-send-email.sh      | 27 ++++++++++++++++++++--
>>  3 files changed, 75 insertions(+), 25 deletions(-)
>>
>> diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
>> index a16e62bc8c..0decbfc92d 100644
>> --- a/Documentation/githooks.txt
>> +++ b/Documentation/githooks.txt
>> @@ -583,10 +583,29 @@ processed by rebase.
>>  sendemail-validate
>>  ~~~~~~~~~~~~~~~~~~
>>  
>> -This hook is invoked by linkgit:git-send-email[1].  It takes a single parameter,
>> -the name of the file that holds the e-mail to be sent.  Exiting with a
>> -non-zero status causes `git send-email` to abort before sending any
>> -e-mails.
>> +This hook is invoked by linkgit:git-send-email[1].
>> +
>> +It takes these command line arguments. They are,
>> +1. the name of the file which holds the contents of the email to be sent.
>> +2. The name of the file which holds the SMTP headers of the email.
>> +
>> +The SMTP headers are passed in the exact same way as they are passed to the
>> +user's Mail Transport Agent (MTA). In effect, the email given to the user's
>> +MTA, is the contents of $2 followed by the contents of $1.
>> +
>> +Below is an example for a few common headers. Take notice of the
> "example of" not "for".
>
> This maybe clearer:
> "An example of a few common headers is shown below. Take notice ..."

>> +capitalization and multi-line tab structure.
>> +
>> +  From: Example <from@example.com>
>> +  To: to@example.com
>> +  Cc: cc@example.com,
>> +	  A <author@example.com>,
>> +	  One <one@example.com>,
>> +	  two@example.com
>> +  Subject: PATCH-STRING
>> +
>> +Exiting with a non-zero status causes `git send-email` to abort
>> +before sending any e-mails.
>>  
>>  fsmonitor-watchman
>>  ~~~~~~~~~~~~~~~~~~
>> diff --git a/git-send-email.perl b/git-send-email.perl
>> index 42f135a266..0e595d6ac5 100755
>> --- a/git-send-email.perl
>> +++ b/git-send-email.perl
>> @@ -785,16 +785,31 @@ sub is_format_patch_arg {
>>  	push @files, $repo->command('format-patch', '-o', File::Temp::tempdir(CLEANUP => 1), @rev_list_opts);
>>  }
>>  
>> -@files = handle_backup_files(@files);
>> +if (defined $sender) {
>> +	$sender =~ s/^\s+|\s+$//g;
>> +	($sender) = expand_aliases($sender);
>> +} else {
>> +	$sender = $repoauthor->() || $repocommitter->() || '';
>> +}
>> +
>> +# $sender could be an already sanitized address
>> +# (e.g. sendemail.from could be manually sanitized by user).
>> +# But it's a no-op to run sanitize_address on an already sanitized address.
>> +$sender = sanitize_address($sender);
>> +
>> +$time = time - scalar $#files;
>>  
>>  if ($validate) {
>>  	foreach my $f (@files) {
>>  		unless (-p $f) {
>> +		        pre_process_file($f, 1);
>>  			validate_patch($f, $target_xfer_encoding);
>>  		}
>>  	}
>>  }
>>  
>> +@files = handle_backup_files(@files);
>> +
>>  if (@files) {
>>  	unless ($quiet) {
>>  		print $_,"\n" for (@files);
>> @@ -1043,18 +1058,6 @@ sub file_declares_8bit_cte {
>>  	}
>>  }
>>  
>> -if (defined $sender) {
>> -	$sender =~ s/^\s+|\s+$//g;
>> -	($sender) = expand_aliases($sender);
>> -} else {
>> -	$sender = $repoauthor->() || $repocommitter->() || '';
>> -}
>> -
>> -# $sender could be an already sanitized address
>> -# (e.g. sendemail.from could be manually sanitized by user).
>> -# But it's a no-op to run sanitize_address on an already sanitized address.
>> -$sender = sanitize_address($sender);
>> -
>>  my $to_whom = __("To whom should the emails be sent (if anyone)?");
>>  my $prompting = 0;
>>  if (!@initial_to && !defined $to_cmd) {
>> @@ -1214,10 +1217,6 @@ sub make_message_id {
>>  	#print "new message id = $message_id\n"; # Was useful for debugging
>>  }
>>  
>> -
>> -
>> -$time = time - scalar $#files;
>> -
>>  sub unquote_rfc2047 {
>>  	local ($_) = @_;
>>  	my $charset;
>> @@ -2101,11 +2100,20 @@ sub validate_patch {
>>  			chdir($repo->wc_path() or $repo->repo_path())
>>  				or die("chdir: $!");
>>  			local $ENV{"GIT_DIR"} = $repo->repo_path();
>> +
>> +			my ($recipients_ref, $to, $date, $gitversion, $cc, $ccline, $header) = gen_header();
>> +
>> +			require File::Temp;
>> +			my ($header_filehandle, $header_filename) = File::Temp::tempfile(
>> +                            ".gitsendemail.header.XXXXXX", DIR => $repo->repo_path());
>> +			print $header_filehandle $header;
>> +
>>  			my @cmd = ("git", "hook", "run", "--ignore-missing",
>>  				    $hook_name, "--");
>> -			my @cmd_msg = (@cmd, "<patch>");
>> -			my @cmd_run = (@cmd, $target);
>> +			my @cmd_msg = (@cmd, "<patch>", "<header>");
>> +			my @cmd_run = (@cmd, $target, $header_filename);
>>  			$hook_error = system_or_msg(\@cmd_run, undef, "@cmd_msg");
>> +			unlink($header_filehandle);
>>  			chdir($cwd_save) or die("chdir: $!");
>>  		}
>>  		if ($hook_error) {
>> diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
>> index 1130ef21b3..8a5c111a24 100755
>> --- a/t/t9001-send-email.sh
>> +++ b/t/t9001-send-email.sh
>> @@ -540,7 +540,7 @@ test_expect_success $PREREQ "--validate respects relative core.hooksPath path" '
>>  	test_path_is_file my-hooks.ran &&
>>  	cat >expect <<-EOF &&
>>  	fatal: longline.patch: rejected by sendemail-validate hook
>> -	fatal: command '"'"'git hook run --ignore-missing sendemail-validate -- <patch>'"'"' died with exit code 1
>> +	fatal: command '"'"'git hook run --ignore-missing sendemail-validate -- <patch> <header>'"'"' died with exit code 1
>>  	warning: no patches were sent
>>  	EOF
>>  	test_cmp expect actual
>> @@ -559,12 +559,35 @@ test_expect_success $PREREQ "--validate respects absolute core.hooksPath path" '
>>  	test_path_is_file my-hooks.ran &&
>>  	cat >expect <<-EOF &&
>>  	fatal: longline.patch: rejected by sendemail-validate hook
>> -	fatal: command '"'"'git hook run --ignore-missing sendemail-validate -- <patch>'"'"' died with exit code 1
>> +	fatal: command '"'"'git hook run --ignore-missing sendemail-validate -- <patch> <header>'"'"' died with exit code 1
>>  	warning: no patches were sent
>>  	EOF
>>  	test_cmp expect actual
>>  '
>>  
>> +test_expect_success $PREREQ "--validate hook supports header argument" '
>> +	write_script my-hooks/sendemail-validate <<-\EOF &&
>> +        if test "$#" -ge 2
>> +	then
> There appears to be an extra indentation of the "if" statement.