if (StringUtil.isBlank(responseContentType)) {
                    response.setHeader("Content-Type", "application/json");
                } else {
                    response.setHeader("Content-Type", responseContentType);
                }
                CopyUtil.copy(in, out);
            } catch (final ClientAbortException e) {

        }

        // Set SSE headers
        response.setContentType("text/event-stream");
        response.setCharacterEncoding("UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Connection", "keep-alive");
        response.setHeader("X-Accel-Buffering", "no"); // Disable nginx buffering

        try (final PrintWriter writer = response.getWriter()) {

        }
    }

    @Override
    protected void writeHeaders(final HttpServletResponse response) {
        ComponentUtil.getFessConfig().getApiJsonResponseHeaderList().forEach(e -> response.setHeader(e.getFirst(), e.getSecond()));
    }

    /**
     * Writes a JSON response.
     * @param status The status code.
     * @param t The throwable.
     */

            for (final String s : context.fessConfig.getSearchlogRequestHeadersAsArray()) {
                final String key = s.replace('-', '_').toLowerCase(Locale.ENGLISH);
                Collections.list(context.request.getHeaders(s)).stream().forEach(v -> {
                    searchLog.addRequestHeaderValue(key, v);
                });
            }
        }

        if (StringUtil.isNotBlank(context.virtualHostKey)) {