Custom Bugzilla hook not invoked when using mod_perl

Question

I have added a custom hook to Bugzilla/Install/Util.pm:

# Used by template_include_path.
sub _template_base_directories {
    # ...
    Bugzilla::Hook::process('template_dirs_alter', { template_dirs => \@template_dirs });
    # ...
    return \@template_dirs;
}

When executed via cgi, everything works fine, but using mod_perl I can see using warn() statements that the process statement above is executed for the custom hook, but the actual hook implementation is never invoked.

In Bugzilla/Hook.pm:

sub process {
    my ($name, $args) = @_;
    # ...

    foreach my $extension (@{ Bugzilla->extensions }) {
        if ($extension->can($name)) {
            # log shows the expected hook name and extension
            # so the hook implementation is found
            $extension->$name($args); # should invoke hook implementation, but doesn't
        }
    }
    # ...
}

The hook is implemented in an Extension.pm like so:

sub template_dirs_alter {
    my ($self, $args) = @_;
    my ($template_dirs) = @$args{qw(template_dirs)};

    if($something) {
        push(@$template_dirs, "some/dir/path");
    }
}

Any obvious gotchas with mod_perl and/or the Bugzilla hook/extension system I am missing here?

Answer 1

While the cwd is usually the Bugzilla root when using cgi, it can be anything when using mod_perl (e.g. the apache home).

When using file paths in Bugzilla extensions, always prefix relative paths:

use File::Basename qw(dirname);
our $BASEDIR = dirname(__FILE__);

sub template_dirs_alter {
    my ($self, $args) = @_;
    my ($template_dirs) = @$args{qw(template_dirs)};

    if($something) {
        push(@$template_dirs, $BASEDIR . "some/dir/path");
    }
}