求教，如何从 HttpServletRequest 中获取类名和方法名

[iiicarus]

项目是 Springboot，前后不分离。目前使用的 AOP 记录日志，很全面，都可以记下来。 但是据说 Springboot2 的 HttpTraceFilter 效率更高，但是写了之后不知道怎么从 HttpServletRequest 中获取类名和方法名。 求教：如果一定要采用 HttpTraceFilter 方式记录日志，如何从 HttpServletRequest 中获取方法名和类名？

[iiicarus]

@Configuration
@ConditionalOnWebApplication
public class HttpTraceConfiguration {

@ConditionalOnWebApplication(type = ConditionalOnWebApplication.Type.SERVLET)
static class ServletTraceFilterConfiguration {

@Bean
public HttpTraceLogFilter httpTraceLogFilter(MeterRegistry registry) {
return new HttpTraceLogFilter(registry);
}
}
}

[iiicarus]

@Slf4j
public class HttpTraceLogFilter extends OncePerRequestFilter implements Ordered {

private static final String NEED_TRACE_PATH_PREFIX_BUSINESS = "/business";
private static final String NEED_TRACE_PATH_PREFIX_NPI = "/npi";
private static final String NEED_TRACE_PATH_PREFIX_SYSTEM = "/system";
private static final String IGNORE_CONTENT_TYPE = "multipart/form-data";

private final MeterRegistry registry;

public HttpTraceLogFilter(MeterRegistry registry) {
this.registry = registry;
}

@Override
public int getOrder() {
return Ordered.LOWEST_PRECEDENCE - 10;
}

@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
throws ServletException, IOException {
if (!isRequestValid(request)) {
filterChain.doFilter(request, response);
return;
}
if (!(request instanceof ContentCachingRequestWrapper)) {
request = new ContentCachingRequestWrapper(request);
}
if (!(response instanceof ContentCachingResponseWrapper)) {
response = new ContentCachingResponseWrapper(response);
}

int status = HttpStatus.INTERNAL_SERVER_ERROR.value();
long startTime = System.currentTimeMillis();
try {
filterChain.doFilter(request, response);
status = response.getStatus();
} finally {
String path = request.getRequestURI();
boolean pathFlag = path.startsWith(NEED_TRACE_PATH_PREFIX_BUSINESS) || path.startsWith(NEED_TRACE_PATH_PREFIX_NPI) || path.startsWith(NEED_TRACE_PATH_PREFIX_SYSTEM);
if (pathFlag && !Objects.equals(IGNORE_CONTENT_TYPE, request.getContentType())) {

String requestBody = IOUtils.toString(request.getInputStream(), Charsets.UTF_8);
log.info(requestBody);
//1. 记录日志
HttpTraceLog traceLog = new HttpTraceLog();
traceLog.setPath(path);
log.info("path ===================>: {}", path);
traceLog.setMethod(request.getMethod());
log.info("method ===================>: {}", request.getMethod());
long timeConsuming = System.currentTimeMillis() - startTime;
traceLog.setTimeTaken(timeConsuming);
log.info("timeConsuming ===================>: {} ms", timeConsuming);
//traceLog.setTime(LocalDateTime.now().toString());
//traceLog.setParameterMap(JsonMapper.INSTANCE.toJson(request.getParameterMap()));
traceLog.setStatus(status);
log.info("status ===================>: {}", status);
//traceLog.setRequestBody(getRequestBody(request));
//traceLog.setResponseBody(getResponseBody(response));
//log.info("Http trace log: {}", JsonMapper.INSTANCE.toJson(traceLog));
//log.info("Http trace log: {}===============================================>", traceLog);
}
updateResponse(response);
}
}

private boolean isRequestValid(HttpServletRequest request) {
try {
new URI(request.getRequestURL().toString());
return true;
} catch (URISyntaxException ex) {
return false;
}
}

private String getRequestBody(HttpServletRequest request) {
String requestBody = "";
ContentCachingRequestWrapper wrapper = WebUtils.getNativeRequest(request, ContentCachingRequestWrapper.class);
if (wrapper != null) {
try {
requestBody = IOUtils.toString(wrapper.getContentAsByteArray(), wrapper.getCharacterEncoding());
} catch (IOException e) {
// NOOP
}
}
return requestBody;
}

private String getResponseBody(HttpServletResponse response) {
String responseBody = "";
ContentCachingResponseWrapper wrapper = WebUtils.getNativeResponse(response, ContentCachingResponseWrapper.class);
if (wrapper != null) {
try {
responseBody = IOUtils.toString(wrapper.getContentAsByteArray(), wrapper.getCharacterEncoding());
} catch (IOException e) {
// NOOP
}
}
return responseBody;
}

private void updateResponse(HttpServletResponse response) throws IOException {
ContentCachingResponseWrapper responseWrapper = WebUtils.getNativeResponse(response, ContentCachingResponseWrapper.class);
Objects.requireNonNull(responseWrapper).copyBodyToResponse();
}


@Data
private static class HttpTraceLog {
private String path;
private String parameterMap;
private String method;
private Long timeTaken;
private String time;
private Integer status;
private String requestBody;
private String responseBody;
}
}

[iiicarus]

代码如上

[Aresxue]

假设你想要的是当前请求对象所对应的服务的类名和方法名，是不太好获取的，因为过滤器作用于请求进入 Servlet 之前(对于 Spring MVC 来说是 DispatcherServlet)，而在常用的 Spring MVC 中请求路径转发到服务(比如说 Controller)是在 HandlerMapping 和 HandlerAdapter 中做的，在过滤器中的时候你还不知道这个请求会映射到哪个服务。

建议使用 aop 在请求收发层或业务层做日志记录。

就是想在过滤器中处理的话给个思路，可以自定义服务将请求地址和服务做一一映射，比如初始化一个 HashMap, 请求路径为 key, 服务全名为 value(只是举例，请求路径的匹配是复杂多样的，自定义匹配规则很难做到全面)

最后还有一种骚套路是使用 Spring 的 HandlerMapping 和 HandlerAdapter 做匹配，这种违反规范的做法在正式工程请不要采用。

[iiicarus]

@Aresxue 谢谢！从 request 中获取类名和方法名太困难了，感觉违背了 AOP 存在的意义！我们领导也是非要我这样做，目前的做法是，从路径 path 中分析得到模块。也没有具体的类名和方法名，不过另外做了 AOP，没提交，等后面要的时候再说吧~~~