if (isLoginRequired()) {
            return redirectToLogin();
        }

        Map<String, Object> doc = null;
        try {
            doc = searchHelper.getDocumentByDocId(form.docId, queryFieldConfig.getCacheResponseFields(), getUserBean()).orElse(null);
        } catch (final Exception e) {
            logger.warn("Failed to request: {}", form.docId, e);
        }
        if (doc == null) {

        ComponentUtil.register(new KeyMatchHelper(), "keyMatchHelper");
        inject(queryHelper);
        queryFieldConfig = new QueryFieldConfig();
        ComponentUtil.register(queryFieldConfig, "queryFieldConfig");
        queryFieldConfig.init();
        QueryProcessor queryProcessor = new QueryProcessor();
        ComponentUtil.register(queryProcessor, "queryProcessor");

        if (isLoginRequired()) {
            return redirectToLogin();
        }

        final Map<String, Object> doc =
                searchHelper.getDocumentByDocId(form.docId, queryFieldConfig.getResponseFields(), getUserBean()).orElse(null);
        final String url = DocumentUtil.getValue(doc, fessConfig.getIndexFieldThumbnail(), String.class);