sub interestedIn {
    my ($self, $plugin) = @_;
    return int(defined($plugin->can('buildFinished')));
}

sub interestedIn {
    my ($self, $plugin) = @_;
    return int(defined($plugin->can('buildQueued')));
}

sub interestedIn {
    my ($self, $plugin) = @_;
    return int(defined($plugin->can('buildStarted')));
}

sub interestedIn {
    my ($self, $plugin) = @_;
    return int(defined($plugin->can('stepFinished')));
}

}
sub interested {
    my ($self, $plugin) = @_;
    return $self->{"event"}->interestedIn($plugin);

# Called when build $build has been queued.
sub buildQueued {
    my ($self, $build) = @_;
}

# To implement behaviors in response to the following events, implement
# the function in your plugin and it will be executed by hydra-notify.
#
# See the tests in t/Event/*.t for arguments, and the documentation for
# notify events for semantics.
#
# # Called when build $build has been queued.
# sub buildQueued {
#     my ($self, $build) = @_;
# }

# Called when build $build has started.
sub buildStarted {
    my ($self, $build) = @_;
}

# # Called when build $build has started.
# sub buildStarted {
#     my ($self, $build) = @_;
# }

# Called when build $build has finished.  If the build failed, then
# $dependents is an array ref to a list of builds that have also
# failed as a result (i.e. because they depend on $build or a failed
# dependeny of $build).
sub buildFinished {
    my ($self, $build, $dependents) = @_;
}

# # Called when build $build has finished.  If the build failed, then
# # $dependents is an array ref to a list of builds that have also
# # failed as a result (i.e. because they depend on $build or a failed
# # dependeny of $build).
# sub buildFinished {
#     my ($self, $build, $dependents) = @_;
# }

# Called when step $step has finished. The build log is stored in the
# file $logPath (bzip2-compressed).
sub stepFinished {
    my ($self, $step, $logPath) = @_;
}

# # Called when step $step has finished. The build log is stored in the
# # file $logPath (bzip2-compressed).
# sub stepFinished {
#     my ($self, $step, $logPath) = @_;
# }

    );
    $prometheus->declare(
        "notify_plugin_not_interested",
        type => "counter",
        help => "Number of tasks that have not been processed because the plugin was not interested in the event."

    if (!$task->{"event"}->interested($plugin)) {
        $self->{"prometheus"}->inc("notify_plugin_not_interested", $event_labels);
        return 0;
    }

subtest "interested" => sub {
    my $event = Hydra::Event::BuildFinished->new(123, []);
    subtest "A plugin which does not implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => ();
        is($event->interestedIn($plugin), 0, "The plugin is not interesting.");
    };
    subtest "A plugin which does implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => (
            add => [
                "buildFinished" => sub {}
            ]
        );

        is($event->interestedIn($plugin), 1, "The plugin is interesting.");
    };
};

};
subtest "interested" => sub {
    my $event = Hydra::Event::BuildQueued->new(123, []);
    subtest "A plugin which does not implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => ();
        is($event->interestedIn($plugin), 0, "The plugin is not interesting.");
    };
    subtest "A plugin which does implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => (
            add => [
                "buildQueued" => sub {}
            ]
        );
        is($event->interestedIn($plugin), 1, "The plugin is interesting.");
    };

};
subtest "interested" => sub {
    my $event = Hydra::Event::BuildStarted->new(123, []);
    subtest "A plugin which does not implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => ();
        is($event->interestedIn($plugin), 0, "The plugin is not interesting.");
    };
    subtest "A plugin which does implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => (
            add => [
                "buildStarted" => sub {}
            ]
        );
        is($event->interestedIn($plugin), 1, "The plugin is interesting.");
    };

};
subtest "interested" => sub {
    my $event = Hydra::Event::StepFinished->new(123, []);
    subtest "A plugin which does not implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => ();
        is($event->interestedIn($plugin), 0, "The plugin is not interesting.");
    };
    subtest "A plugin which does implement the API" => sub {
        my $plugin = {};
        my $mock = mock_obj $plugin => (
            add => [
                "stepFinished" => sub {}
            ]
        );
        is($event->interestedIn($plugin), 1, "The plugin is interesting.");
    };