@GetMapping("/signatureImage/{path}")
    public void signatureImage(@PathVariable("path") String realFilePath, HttpServletResponse response) throws IOException {
        //realFilePath = "/20231206/qhyu.png"
        String fileName = "qhyu.png"; //可以切割獲取。
        String path = "/upload/signature"; // 固定的存放路徑
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        try (Ftp ftp = new Ftp("Ftp_address", "Ftp_port", "username", "password")) {
            ftp.download(path+realFilePath, fileName, outputStream);
        } catch (Exception e) {
            log.error("FTP文件下載出錯:{}", e.getMessage());
            throw new QhyuException(MessageCode.FILE_DOENLOAD_ERROR.getCode());
        }
        // 將內(nèi)存中的文件內(nèi)容轉(zhuǎn)換為輸入流
        InputStream inputStream = new ByteArrayInputStream(outputStream.toByteArray());
        // 設(shè)置響應(yīng)的內(nèi)容類型為圖片格式
        String contentType = MediaType.IMAGE_PNG_VALUE; // 假設(shè)為PNG格式
        response.setContentType(contentType);
        org.apache.commons.io.IOUtils.copy(inputStream, response.getOutputStream());
        response.flushBuffer();
        // 關(guān)閉內(nèi)存流和FTP連接
        inputStream.close();
        outputStream.close();
    }

    server {
        listen       10086;
        charset utf-8;
        access_log      /var/log/nginx/qhyu/qhyu_access.log;
        error_log      /var/log/nginx/qhyu/qhyu_error.log;
   location /verify {
        proxy_pass http://host:port/api/signatureImage/validate?realFilePath=$arg_realFilePath&signature=$arg_signature;
        proxy_set_header Host $host;
        proxy_intercept_errors on;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_buffering off;
        error_page 418 = @custom_redirect;
        error_page 420 = @custom_error;
     }
      location @custom_error{
        default_type application/json;
        return 200 'error image';
      }
      location @custom_redirect {
        rewrite ^ /signature/$arg_realFilePath last;
      }
      location /signature {
        alias /upload/signature/;
      }
}
}

@GetMapping("/signatureImage/validate")
    public Object signatureValidate(String realFilePath,String signature,HttpServletResponse httpServletResponse){
        String redisKey = AesEncryptUtil.decryption(signature);
        if (StrUtil.isBlank(redisKey)){
            httpServletResponse.setStatus(420);
            return RenderResult.success();
        }
        Object value = redisService.get(redisKey);
        if (value == null) {
            httpServletResponse.setStatus(420);
            return RenderResult.success();
        }
        List<String> signatureUrls = JSON.parseArray(JSON.toJSONString(value), String.class);
        if (signatureUrls == null || signatureUrls.isEmpty()){
            httpServletResponse.setStatus(420);
            return RenderResult.success();
        }
        if (!signatureUrls.contains(realFilePath)){
            httpServletResponse.setStatus(420);
            return RenderResult.success();
        }
        // greater than or equal to 300 should be passed to a client or be intercepted and redirected to nginx
        // for processing with the error_page directive
        // http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_intercept_errors
        httpServletResponse.setStatus(418);
        return RenderResult.success();
    }