如何在HandlerInterceptor中读取请求体？

Question

我有 Spring Boot，我需要在数据库中记录用户操作，所以我编写了 HandlerInterceptor：

@Component
public class LogInterceptor implements HandlerInterceptor {
@Autovired
private LogUserActionService logUserActionService;
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) 
throws IOException {
    String userName = SecurityContextHolder.getContext().getAuthentication().getName();
    String url = request.getRequestURI();
    String queryString = request.getQueryString() != null ? request.getQueryString() : "";
    String body = "POST".equalsIgnoreCase(request.getMethod()) ? new BufferedReader(new InputStreamReader(request.getInputStream())).lines().collect(Collectors.joining(System.lineSeparator())) : queryString;
    logUserActionService.logUserAction(userName, url, body);
    return true;
}
}

但根据这个答案Get RequestBody and ResponseBody at HandlerInterceptor "RequestBody can be read only Once"，所以据我了解，我读取输入流，然后 Spring 尝试执行相同的操作，但流已被读取，并且我收到错误： “缺少所需的请求正文......”

所以我尝试了不同的方法来制作缓冲输入流，即：

HttpServletRequest httpServletRequest = new ContentCachingRequestWrapper(request);
new BufferedReader(new InputStreamReader(httpServletRequest.getInputStream())).lines().collect(Collectors.joining(System.lineSeparator()))

或者

InputStream bufferedInputStream = new BufferedInputStream(request.getInputStream());

但没有任何帮助我也尝试使用

@ControllerAdvice
public class UserActionRequestBodyAdviceAdapter extends RequestBodyAdviceAdapter {

但它只有正文，没有 URL 或请求参数等请求信息 也尝试使用过滤器，但结果相同。

因此，我需要一种好方法来从请求中获取信息，如用户、URL、参数、正文（如果存在）并将其写入数据库。

Answer 1

要记录 HTTP 请求和响应，您可以使用RequestBodyAdviceAdapter和ResponseBodyAdvice。在这里，它按照我的方式使用。

CustomRequestBodyAdviceAdapter.java

@ControllerAdvice
public class CustomRequestBodyAdviceAdapter extends RequestBodyAdviceAdapter {

    @Autowired
    HttpServletRequest httpServletRequest;

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

    @Override
    public Object afterBodyRead(Object body, HttpInputMessage inputMessage, MethodParameter parameter, Type targetType,
            Class<? extends HttpMessageConverter<?>> converterType) {

        // here you can full log httpServletRequest and body.

        return super.afterBodyRead(body, inputMessage, parameter, targetType, converterType);
    }
}

CustomResponseBodyAdviceAdapter.java

@ControllerAdvice
public class CustomResponseBodyAdviceAdapter implements ResponseBodyAdvice<Object> {

    @Autowired
    private LoggingService loggingService;

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

    @Override
    public Object beforeBodyWrite(Object o, MethodParameter methodParameter, MediaType mediaType,
            Class<? extends HttpMessageConverter<?>> aClass, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {
        if (serverHttpRequest instanceof ServletServerHttpRequest && serverHttpResponse instanceof ServletServerHttpResponse) {

            // here you can full log httpServletRequest and body.
        }
        return o;
    }
}

上面AdviceAdapter无法处理该GET请求。所以，你可以使用HandlerInterceptor.

CustomWebConfigurerAdapter.java

@Component
public class CustomWebConfigurerAdapter implements WebMvcConfigurer {

   @Autowired
   private CustomLogInterceptor httpServiceInterceptor;

   @Override
   public void addInterceptors(InterceptorRegistry registry) {
      registry.addInterceptor(httpServiceInterceptor);
   }
}

CustomLogInterceptor.java

@Component
public class CustomLogInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        if (DispatcherType.REQUEST.name().equals(request.getDispatcherType().name()) && request.getMethod().equals(HttpMethod.GET.name())) {

            // here you can full log httpServletRequest and body for GET Request.

        }
        return true;
    }
}

在这里你可以参考我的 git 中的完整源代码。

springboot-http-request-response-logging-with-json-logger

+功能=>它已经与ELK集成（Elasticsearch，Logstash，Kibana）

Answer 2

您可以用来Filter记录请求正文。

public class LoggingFilter implements Filter {

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) req;
        ContentCachingRequestWrapper wrappedRequest = new ContentCachingRequestWrapper(request);
        try {
            chain.doFilter(wrappedRequest, res);
        } finally {
            logRequestBody(wrappedRequest);
        }
    }

    private static void logRequestBody(ContentCachingRequestWrapper request) {

        byte[] buf = request.getContentAsByteArray();
        if (buf.length > 0) {
            try {
                String requestBody = new String(buf, 0, buf.length, request.getCharacterEncoding());
                System.out.println(requestBody);
            } catch (Exception e) {
                System.out.println("error in reading request body");
            }
        }
    }
}

这里要注意的主要事情是，您必须ContentCachingRequestWrapper在过滤器链中传递对象，否则您将无法在其中获取请求内容。

在上面的示例中，如果您使用chain.doFilter(req, res)或chain.doFilter(request, res)那么您将不会在wrappedRequest对象中获得请求正文。