return null;
    }

    @SuppressWarnings("unchecked")
    private ConcurrentMap<Key, PluginVersionResult> getCache(PluginVersionRequest request) {
        SessionData data = request.getRepositorySession().getData();
        return (ConcurrentMap<Key, PluginVersionResult>)
                data.computeIfAbsent(CACHE_KEY, () -> new ConcurrentHashMap<>(256));
    }

    private static Key getKey(PluginVersionRequest request) {