升級SpringCloud到Hoxton.SR3後SpringMVC的端點路徑映射不打印,分析和解決

升級版本就是事多...

SpringMVC版本5.2.4.RELEASE

版本信息

升級前版本

SpringBoot	SpringCloud	SpringMVC
2.0.6.RELEASE	Finchley.SR2	5.0.10.RELEASE

升級後版本

SpringBoot	SpringCloud	SpringMVC
2.2.5.RELEASE	Hoxton.SR3	5.2.4.RELEASE

 

升級版本後發現啓動時SpringMVC框架的端點路徑映射不打印了, 有時候開發的時候可能會看看是沒有註冊映射

源碼分析

這是新版本的SpringMVC註冊路徑的地方, 這個地方在舊版本中會有logger.info()的路徑映射的日誌打印, 新版是直接將打印日誌的代碼給刪除掉了...

org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.MappingRegistry#register

public void register(T mapping, Object handler, Method method) {
			// Assert that the handler method is not a suspending one.
			if (KotlinDetector.isKotlinType(method.getDeclaringClass()) && KotlinDelegate.isSuspend(method)) {
				throw new IllegalStateException("Unsupported suspending handler method detected: " + method);
			}
			this.readWriteLock.writeLock().lock();
			try {
				HandlerMethod handlerMethod = createHandlerMethod(handler, method);
				validateMethodMapping(handlerMethod, mapping);
				this.mappingLookup.put(mapping, handlerMethod);

				List<String> directUrls = getDirectUrls(mapping);
				for (String url : directUrls) {
					this.urlLookup.add(url, mapping);
				}

				String name = null;
				if (getNamingStrategy() != null) {
					name = getNamingStrategy().getName(handlerMethod, mapping);
					addMappingName(name, handlerMethod);
				}

				CorsConfiguration corsConfig = initCorsConfiguration(handler, method, mapping);
				if (corsConfig != null) {
					this.corsLookup.put(handlerMethod, corsConfig);
				}

				this.registry.put(mapping, new MappingRegistration<>(mapping, handlerMethod, directUrls, name));
			}
			finally {
				this.readWriteLock.writeLock().unlock();
			}
		}

但是我向上找還是發現了打印路徑映射日誌的地方

org.springframework.web.servlet.handler.AbstractHandlerMethodMapping#detectHandlerMethods

/**
	 * Look for handler methods in the specified handler bean.
	 * @param handler either a bean name or an actual handler instance
	 * @see #getMappingForMethod
	 */
	protected void detectHandlerMethods(Object handler) {
		Class<?> handlerType = (handler instanceof String ?
				obtainApplicationContext().getType((String) handler) : handler.getClass());

		if (handlerType != null) {
			Class<?> userType = ClassUtils.getUserClass(handlerType);
			Map<Method, T> methods = MethodIntrospector.selectMethods(userType,
					(MethodIntrospector.MetadataLookup<T>) method -> {
						try {
							return getMappingForMethod(method, userType);
						}
						catch (Throwable ex) {
							throw new IllegalStateException("Invalid mapping on handler class [" +
									userType.getName() + "]: " + method, ex);
						}
					});
			if (logger.isTraceEnabled()) {
// 這裏還可以打印路徑映射信息
				logger.trace(formatMappings(userType, methods));
			}
			methods.forEach((method, mapping) -> {
				Method invocableMethod = AopUtils.selectInvocableMethod(method, userType);
				registerHandlerMethod(handler, invocableMethod, mapping);
			});
		}
	}

這裏是對整個Controller類中包含的路徑進行循環遍歷註冊的地方,

這裏判斷了是否打開trace級別的日誌輸出, 如果開啓的話就會打印這個controller包含的所有路徑映射(路徑與方法), 這裏在舊版本打印的只是controller包含的路徑映射的數量

日誌格式

2020-04-10 14:09:19.901  [ main:21367 ] - [TRACE ,,, ] c.x.s.a.c.WebMvcConfig$FeignRequestMappingHandlerMapping#detectHandlerMethods:284 - 
	c.x.s.i.c.ItemUnitController:
	{GET /item/itemUnit/findById}: findById(Long)
	{GET /item/itemUnit/loaderItemUnits}: loaderItemUnits()
	{GET /item/itemUnit/getItemUnit}: getItemUnit(Long)
	{GET /item/itemUnit/findUnitByName}: findUnitByName(String)
	{GET /item/itemUnit/findAllItemUnit}: loadItemUnit()

解決辦法

修改配置類的日誌級別爲trace就好了

application.yml

logging:
  level:
    # 輸出端點映射
    com.xxx.xxx.config.WebMvcConfig: trace

這裏WebMvcConfig類是我們項目繼承WebMvcConfigurationSupport做的一些自定義配置的類, 改成自己項目的mvc配置類就好了

怎麼找自己的配置類?

在這句代碼上下個斷點 if (logger.isTraceEnabled()) {

斷下來之後執行表達式logger.getName()得到的類名就是你的配置類名