@RequestBody 无法转换从 AES 加密字符串派生的 object

Question

从客户端传递带有内容类型文本/纯文本的AES加密字符串。

AES 加密字符串在通过过滤器到达 controller 之前被解密。

自定义加密过滤器

@Component
@Order(0) 
public class CustomEncryptedFilter implements Filter {

    private static final Logger logger = LogManager.getLogger(CustomEncryptedFilter.class.getName());

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    throws IOException, ServletException {

        logger.info("************** Encryption Filter - START ***********************");
        String encryptedString = IOUtils.toString(request.getInputStream());
        if (encryptedString != null && encryptedString.length() > 0) {

            byte[] decryptedString = new AESEncrytion().decrypt(encryptedString).getBytes();

            if (request instanceof HttpServletRequest) {

                HttpServletRequest httpServletRequest = (HttpServletRequest) request;
                CustomHttpServletRequestWrapper requestWrapper 
                = new CustomHttpServletRequestWrapper(httpServletRequest,decryptedString);
                                                           
                logger.info("Content Type: {}", requestWrapper.getContentType());
                logger.info("Request Body: {}", IOUtils.toString(requestWrapper.getInputStream()));

                chain.doFilter(requestWrapper, response);

            } else {

                chain.doFilter(request, response);
            }

        } else {

            logger.info("Request is Invalid or Empty");
            chain.doFilter(request, response);
        }

    }

}

在这里，我将获取当前请求正文，它是一个 AES 加密字符串，然后将其解密以转换为字符串。

encrypted String - Ijwmn5sZ5HqoUPb15c5idjxetqmC8Sln6+d2BPaYzxA=
Original String  - {"username":"thivanka"}

在获得解密的字符串（Json 对象）后，我通过扩展HttpServletRequestWrapper将其附加到请求正文中

public class CustomHttpServletRequestWrapper extends HttpServletRequestWrapper {

    private static final Logger logger = LogManager.getLogger(CustomHttpServletRequestWrapper.class.getName());

    private ByteArrayInputStream requestBody;

    public CustomHttpServletRequestWrapper(HttpServletRequest request, byte[] decryptedString) {
        super(request);
        try {
            requestBody = new ByteArrayInputStream(decryptedString);
        } catch (Exception e) {
            logger.error(e);
            e.printStackTrace();
        }
    }

    @Override
    public String getHeader(String headerName) {
        String headerValue = super.getHeader(headerName);
        if ("Accept".equalsIgnoreCase(headerName)) {
            return headerValue.replaceAll(MediaType.TEXT_PLAIN_VALUE, MediaType.APPLICATION_JSON_VALUE);
        } else if ("Content-Type".equalsIgnoreCase(headerName)) {
            return headerValue.replaceAll(MediaType.TEXT_PLAIN_VALUE, MediaType.APPLICATION_JSON_VALUE);
        }
        return headerValue;
    }

    @SuppressWarnings("unchecked")
    @Override
    public Enumeration getHeaderNames() {

        HttpServletRequest request = (HttpServletRequest) getRequest();

        List list = new ArrayList();

        Enumeration e = request.getHeaderNames();
        while (e.hasMoreElements()) {
            
            String headerName = (String) e.nextElement();
            String headerValue = request.getHeader(headerName);

            if ("Accept".equalsIgnoreCase(headerName)) {
                headerValue.replaceAll(MediaType.TEXT_PLAIN_VALUE, MediaType.APPLICATION_JSON_VALUE);
            } else if ("Content-Type".equalsIgnoreCase(headerName)) {
                headerValue.replaceAll(MediaType.TEXT_PLAIN_VALUE, MediaType.APPLICATION_JSON_VALUE);
            }
            list.add(headerName);
        }
        return Collections.enumeration(list);
    }

    @SuppressWarnings("unchecked")
    @Override
    public Enumeration getHeaders(final String headerName) {

        HttpServletRequest request = (HttpServletRequest) getRequest();

        List list = new ArrayList();

        Enumeration e = request.getHeaders(headerName);
        
        while (e.hasMoreElements()) {

            String header = e.nextElement().toString();

            if (header.equalsIgnoreCase(MediaType.TEXT_PLAIN_VALUE)) {
                header = MediaType.APPLICATION_JSON_VALUE;
            }
            
            list.add(header);
        }
        return Collections.enumeration(list);
    }

    @Override
    public String getContentType() {
        String contentTypeValue = super.getContentType();
        if (MediaType.TEXT_PLAIN_VALUE.equalsIgnoreCase(contentTypeValue)) {
            return MediaType.APPLICATION_JSON_VALUE;
        }
        return contentTypeValue;
    }

    @Override
    public BufferedReader getReader() throws UnsupportedEncodingException {
        return new BufferedReader(new InputStreamReader(requestBody, "UTF-8"));
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        return new ServletInputStream() {
            @Override
            public int read() {
                return requestBody.read();
            }

            @Override
            public boolean isFinished() {
                // TODO Auto-generated method stub
                return false;
            }

            @Override
            public boolean isReady() {
                // TODO Auto-generated method stub
                return false;
            }

            @Override
            public void setReadListener(ReadListener listener) {
                // TODO Auto-generated method stub

            }
        };
    }

}

除了添加新的请求正文之外，我还将 MediaType 从text/plain更改为application/json ，以便我的 @RequestBody 注释获取媒体类型并执行 object 转换。

这是我的Controller

@CrossOrigin(origins = "*", allowedHeaders = "*")
@RestController
@RequestMapping("/api/mobc")
public class HomeController {
    
    private static final Logger logger = LogManager.getLogger(HomeController.class.getName());
    
    @RequestMapping(value="/hello", method=RequestMethod.POST,consumes="application/json", produces="application/json")
    public ResponseEntity<?> Message(@RequestBody LoginForm loginForm,HttpServletRequest request) { 
        
        logger.info("In Home Controller");
        logger.info("Content Type: {}", request.getContentType());
        
        return ResponseEntity.status(HttpStatus.OK).body(loginForm);
    }

}

LoginForm Object（为了便于阅读，我删除了 Getters/Setters）

公共 class LoginForm {

private String username;

private String password;

}

不幸的是我得到了错误。 我在这里做错了什么。

ExceptionHandlerExceptionResolver - Resolved [org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing

Answer 1

可能的问题

我想IOUtils.toString(InputStream stream)从InputStream读取所有字节。 但是InputStream只能读取一次。

您的日志记录语句

logger.info("Request Body: {}", IOUtils.toString(requestWrapper.getInputStream()));

读取InputStream ，因此 Spring 无法再次读取它。 尝试用new String(encryptedString, Charset.defaultCharset())替换IOUtils.toString(requestWrapper.getInputStream()) )) 。

其他实施方案

您可以实现自定义RequestBodyAdvice ，它将解密消息并在需要时更改标头。

从 Spring 的 JavaDoc 开始：

该合约的实现可以直接使用 RequestMappingHandlerAdapter 注册，或者更可能使用 @ControllerAdvice 进行注释，在这种情况下它们会被自动检测到。

这是一个建议的示例实现，它将消息的第一个字节更改为{并将最后一个字节更改为} 。 您的实现可以修改解密它的消息。

@ControllerAdvice
class CustomRequestBodyAdvice extends RequestBodyAdviceAdapter {

    @Override
    public boolean supports(MethodParameter methodParameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {
        return true;
    }

    @Override
    public HttpInputMessage beforeBodyRead(HttpInputMessage inputMessage, MethodParameter parameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) throws IOException {
        try (InputStream inputStream = inputMessage.getBody()) {
            byte[] bytes = inputStream.readAllBytes();
            bytes[0] = 0x7b; // 0x7b = '{'
            bytes[bytes.length - 1] = 0x7d; // 0x7d = '}'
            return new CustomMessage(new ByteArrayInputStream(bytes), inputMessage.getHeaders());
        }
    }
}

class CustomMessage implements HttpInputMessage {

    private final InputStream body;
    private final HttpHeaders httpHeaders;

    public CustomMessage(InputStream body, HttpHeaders httpHeaders) {
        this.body = body;
        this.httpHeaders = httpHeaders;
    }

    @Override
    public InputStream getBody() throws IOException {
        return this.body;
    }

    @Override
    public HttpHeaders getHeaders() {
        return this.httpHeaders;
    }
}

此外，还有一个RequestBodyAdvice supports 在此示例中，此方法始终返回true ，但您可以创建自定义注释并检查其是否存在。

// custom annotation
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@interface AesEncrypted {}

// class: CustomRequestBodyAdvice
@Override
public boolean supports(MethodParameter methodParameter, Type targetType, Class<? extends HttpMessageConverter<?>> converterType) {
    return methodParameter.hasParameterAnnotation(AesEncrypted.class);
}

// controller
@PostMapping("one")
String getDecrypted(@AesEncrypted @RequestBody Data data) {
    return data.value;
}

Answer 2

如果有人为此而苦苦挣扎，那么答案是转移到 ContentCachingRequestWrapper。 其他方法是使用@geobreze 建议的面向方面的变体来解决相同的问题。

我只需要修改我的 HttpServletRequestWrapper 以促进更改。

参考-> https://www.baeldung.com/spring-reading-httpservletrequest-multiple-times

此 class 通过使用 InputStream 缓存请求正文。 如果我们在其中一个过滤器中读取 InputStream，那么过滤器链中的其他后续过滤器将无法再读取它。 由于此限制，此 class 并非适用于所有情况。