在系统 A->B->C 之间发送文件，而不将整个文件存储在 B 中

我有3个单独的弹簧Web应用程序

• A使用弹簧4.x
• B 使用弹簧 3.2.0
• C 使用弹簧 4.x

B 和 C 公开了用于上传文件的 REST 控制器

• A 读取文件并将其上载到 B
• B 将请求发送到 C，无需读取文件内容
• 然后C对文件做任何它想要的操作。

因此，流量将为 A->B->C

我的问题是 - 是否可以以这种方式设置B，以便B不会将整个文件存储在内存中，而是读取传入的流并将其转发到C？

我设法做的是：A

public void sendFileFromA() throws FileNotFoundException {
    final InputStream fis = new FileInputStream(new File("someFile"));
    final RequestCallback requestCallback = new RequestCallback() {
        @Override
        public void doWithRequest(final ClientHttpRequest request) throws IOException {
            request.getHeaders().add("Content-type", "application/octet-stream");
            IOUtils.copy(fis, request.getBody());
        }
    };
    final RestTemplate restTemplate = new RestTemplate();
    SimpleClientHttpRequestFactory requestFactory = new SimpleClientHttpRequestFactory();
    requestFactory.setBufferRequestBody(false);
    restTemplate.setRequestFactory(requestFactory);

    final HttpMessageConverterExtractor<String> responseExtractor = new HttpMessageConverterExtractor<>(
            String.class, restTemplate.getMessageConverters());
    restTemplate.execute("http://b_url/upload", HttpMethod.POST, requestCallback, responseExtractor);
}

B

@RequestMapping(value = "/upload", method = RequestMethod.POST)
public @ResponseBody String handleFileUpload(HttpServletRequest request) throws IOException {
    final ServletInputStream input = request.getInputStream();

    final RequestCallback requestCallback = new RequestCallback() {
        @Override
        public void doWithRequest(final ClientHttpRequest request) throws IOException {
            request.getHeaders().add("Content-type", "application/octet-stream");
            try (OutputStream body = request.getBody()) {
                IOUtils.copy(input, body);
            }
        }
    };
    final RestTemplate restTemplate = new RestTemplate();
    SimpleClientHttpRequestFactory requestFactory = new SimpleClientHttpRequestFactory();
    requestFactory.setBufferRequestBody(false);
    restTemplate.setRequestFactory(requestFactory);

    final HttpMessageConverterExtractor<String> responseExtractor = new HttpMessageConverterExtractor<>(
            String.class, restTemplate.getMessageConverters());
    restTemplate.execute("http://c_url/upload", HttpMethod.POST, requestCallback, responseExtractor);

    return "success";
}

C

@RequestMapping(value = "/upload", method = RequestMethod.POST)
public @ResponseBody String handleFileUpload(HttpServletRequest request) throws IOException {
    ServletInputStream input = request.getInputStream();

    try (BufferedOutputStream output = new BufferedOutputStream(new FileOutputStream("zibiTest"))) {
        IOUtils.copy(input, output);
    }
    return "success";
}

我可以使用B轻松地将超过>10GB的文件从A复制到C。

使用这样的解决方案，我们可以尝试在传输时停止A，B和C应该收到有关错误的通知，但有时会发生错误消息未到达C的情况 - 它会以套接字超时异常关闭，任何想法为什么会发生这种情况以及如何正确实现它？

这是一种有效的方法，还是可以更好地处理？