Spring HttpServletRequest 在已使用时为空

Question

在获取请求正文后

Class A

，

Class B

正在获取空请求正文。 根据检查是否要注释

Class A

中的代码来检索请求正文，

Class B

将能够获取请求正文。

有没有办法让 HttpServletRequest 不会移除

Class A

中的请求体，Inorder

Class B

仍然可以拿到请求体？

Class A

@Autowired
        private HttpServletRequest request;
  

 public Authentication authenticate(Authentication authentication) throws AuthenticationException {

 String requestBody =  extractBody(request);
            System.out.println("Request Body1: "+requestBody);

....other codes



}

   public static String extractBody(HttpServletRequest request){
        String body = null;
        StringBuilder stringBuilder = new StringBuilder();
        BufferedReader bufferedReader = null;

        try {
            InputStream inputStream = request.getInputStream();
            if (inputStream != null) {
                bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                char[] charBuffer = new char[128];
                int bytesRead = -1;
                while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
                    stringBuilder.append(charBuffer, 0, bytesRead);
                }
            } else {
                stringBuilder.append("");
            }
        } catch (IOException ex) {
            try {
                throw ex;
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } finally {
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                } catch (IOException ex) {
                    try {
                        throw ex;
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                }
            }
        }

        body = stringBuilder.toString();
        return body;
    }

Class B

  public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response,
                                        Authentication authentication) throws IOException, ServletException {

 String requestBody =  extractBody(request);
            System.out.println("Request Body2: "+requestBody);

....other codes

  

}

 public static String extractBody(HttpServletRequest request){
        String body = null;
        StringBuilder stringBuilder = new StringBuilder();
        BufferedReader bufferedReader = null;

        try {
            InputStream inputStream = request.getInputStream();
            if (inputStream != null) {
                bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                char[] charBuffer = new char[128];
                int bytesRead = -1;
                while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
                    stringBuilder.append(charBuffer, 0, bytesRead);
                }
            } else {
                stringBuilder.append("");
            }
        } catch (IOException ex) {
            try {
                throw ex;
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } finally {
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                } catch (IOException ex) {
                    try {
                        throw ex;
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                }
            }
        }

        body = stringBuilder.toString();
        return body;
    }

Answer 1

默认情况下，请求正文只能从 HttpServletRequest 对象中使用一次。

一旦您在 A 类中读取请求正文，输入流可能会被消耗，随后尝试在 B 类中读取请求正文将导致空正文。

要解决这个问题，您可以尝试：

• Read the Request Body Once and Cache It:

  当您读取 A 类中的请求主体时，请在处理之前将其存储在某个位置（例如，在字符串或字节数组中）。然后，你可以将这个缓存的请求体传递给B类。

• Use HttpServletRequestWrapper to Wrap the Request:

  您可以创建 HttpServletRequestWrapper 的自定义实现，该实现重写 getInputStream() 或 getReader() 方法，以在每次调用时返回新的流或读取器。