Git callaback to add issuenumber to commit message

commit-msg

#!/bin/bash
#
# An example hook script to check the commit log message.
# Called by "git commit" with one argument, the name of the file
# that has the commit message.  The hook should exit with non-zero
# status after issuing an appropriate message if it wants to stop the
# commit.  The hook is allowed to edit the commit message file.
#
# Based on another example commit-msg hook I found here: 
# https://review.typo3.org/Documentation/user-changeid.html

CHANGE_ID_AFTER="Bug|Issue"
MSG="$1"
add_ChangeId() {
	clean_message=`sed -e '
		/^diff --git a\/.*/{
			s///
			q
		}
        /^Re #/d
		/^#/d
	' "$MSG" | git stripspace`
	if test -z "$clean_message"
	then
        echo "Clean message ok:"
        echo $clean_message
		return
	fi
    echo "Cleaned message:" 
    echo $clean_message

	if grep -i '^Re: #' "$MSG" >/dev/null
	then
		return
	fi

    echo "Please enter relevant issuenr:"
    exec < /dev/tty

    while true; do
        read -t 100 issueNr
        break
    done

    if [ "$issueNr" = "" ]; then
        echo "No issuenumber entered. Not changing message"
        exit 0
    fi
	perl -e '
		$MSG = shift;
		$id = shift;
		$CHANGE_ID_AFTER = shift;

		undef $/;
		open(I, $MSG); $_ = <I>; close I;
		s|^diff --git a/.*||ms;
		s|^#.*$||mg;
		exit unless $_;

		@message = split /\n/;
		$haveFooter = 0;
		$startFooter = @message;
		for($line = @message - 1; $line >= 0; $line--) {
			$_ = $message[$line];

			if (/^[a-zA-Z0-9-]+:/ && !m,^[a-z0-9-]+://,) {
				$haveFooter++;
				next;
			}
			next if /^[ []/;
			$startFooter = $line if ($haveFooter && /^\r?$/);
			last;
		}

		@footer = @message[$startFooter+1..@message];
		@message = @message[0..$startFooter];
		push(@footer, "") unless @footer;

		for ($line = 0; $line < @footer; $line++) {
			$_ = $footer[$line];
			next if /^($CHANGE_ID_AFTER):/i;
			last;
		}
		splice(@footer, $line, 0, "Re: #$id");

		$_ = join("\n", @message, @footer);
		open(O, ">$MSG"); print O; close O;
	' "$MSG" "$issueNr" "$CHANGE_ID_AFTER"
}

add_ChangeId