修改ZuulHandlerMapping私有变量pathMatcher，重写match方法，使url匹配兼容正则表达式。
一、起源
在mocksever中引入了spring cloud zuul做代理转发，如果请求的url和配置的mock规则匹配（精确匹配和模糊匹配），忽略，不做转发。如果mock配置的url和请求url是完全匹配的，没有问题。例如，请求url：http://localhost:8080/mock/test/query/12345
mock配置：
| url | response |
| /mock/test/query/12435 | {"ret_code":"A00000"} |
但是如果mock的配置url包含正则表达式：/mock/test/query/(\d.*)，ZuulHandlerMapping类中的isIgnoredPath返回false，因为该方法调用的是AntPathMatcher的match方法，而AntPathMatcher的匹配规则是通配符匹配，无法识别正则表达式。
AntPathMatcher基本规则：
1、? 匹配一个字符（除过操作系统默认的文件分隔符）
2、* 匹配0个或多个字符
3、**匹配0个或多个目录
4、{spring:[a-z]+} 将正则表达式[a-z]+匹配到的值,赋值给名为 spring 的路径变量。
二、方案：
1、重写isIgnoredPath方法 ---------无法实现，isIgnoredPath是私有方法。
2、重写match方法 -----------可以实现，math是接口PathMatcher的方法。
三：具体实现
ZuulHandlerMapping源码：
/* * Copyright 2013-2017 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.cloud.netflix.zuul.web; import java.util.Collection; import javax.servlet.http.HttpServletRequest; import org.springframework.boot.autoconfigure.web.ErrorController; import org.springframework.cloud.netflix.zuul.filters.RefreshableRouteLocator; import org.springframework.cloud.netflix.zuul.filters.Route; import org.springframework.cloud.netflix.zuul.filters.RouteLocator; import org.springframework.util.AntPathMatcher; import org.springframework.util.PathMatcher; import org.springframework.web.cors.CorsConfiguration; import org.springframework.web.servlet.HandlerExecutionChain; import org.springframework.web.servlet.handler.AbstractUrlHandlerMapping; import com.netflix.zuul.context.RequestContext; /** * MVC HandlerMapping that maps incoming request paths to remote services. * * @author Spencer Gibb * @author Dave Syer * @author João Salavessa * @author Biju Kunjummen */ public class ZuulHandlerMapping extends AbstractUrlHandlerMapping { private final RouteLocator routeLocator; private final ZuulController zuul; private ErrorController errorController; private PathMatcher pathMatcher = new AntPathMatcher(); private volatile boolean dirty = true; public ZuulHandlerMapping(RouteLocator routeLocator, ZuulController zuul) { this.routeLocator = routeLocator; this.zuul = zuul; setOrder(-200); } @Override protected HandlerExecutionChain getCorsHandlerExecutionChain(HttpServletRequest request, HandlerExecutionChain chain, CorsConfiguration config) { if (config == null) { // Allow CORS requests to go to the backend return chain; } return super.getCorsHandlerExecutionChain(request, chain, config); } public void setErrorController(ErrorController errorController) { this.errorController = errorController; } public void setDirty(boolean dirty) { this.dirty = dirty; if (this.routeLocator instanceof RefreshableRouteLocator) { ((RefreshableRouteLocator) this.routeLocator).refresh(); } } @Override protected Object lookupHandler(String urlPath, HttpServletRequest request) throws Exception { if (this.errorController != null && urlPath.equals(this.errorController.getErrorPath())) { return null; } if (isIgnoredPath(urlPath, this.routeLocator.getIgnoredPaths())) return null; RequestContext ctx = RequestContext.getCurrentContext(); if (ctx.containsKey("forward.to")) { return null; } if (this.dirty) { synchronized (this) { if (this.dirty) { registerHandlers(); this.dirty = false; } } } return super.lookupHandler(urlPath, request); } private boolean isIgnoredPath(String urlPath, Collection<String> ignored) { if (ignored != null) { for (String ignoredPath : ignored) { //pathMatcher 是私有变量，而且被初始化为AntPathMatcher对象 if (this.pathMatcher.match(ignoredPath, urlPath)) { return true; } } } return false; } private void registerHandlers() { Collection<Route> routes = this.routeLocator.getRoutes(); if (routes.isEmpty()) { this.logger.warn("No routes found from RouteLocator"); } else { for (Route route : routes) { registerHandler(route.getFullPath(), this.zuul); } } } }
pathMatcher 是私有变量，而且被初始化为AntPathMatcher对象，假设我们写一个接口PathMatcher的实现类，重写match方法，但是没有办法在isIgnoredPath中被调用到。
想到的是在ZuulHandlerMapping注入到容器的时候，把私有属性pathMatcher初始化成我们定义的新的实现类。
第一步：
修改注入ZuulHandlerMapping的配置类ZuulServerAutoConfiguration、ZuulProxyAutoConfiguration，新建2个类，copy上面2个类的代码，重新命名，例如命名为：
CusZuulServerAutoConfiguration、CusZuulProxyAutoConfiguration。把依赖的类也copy源码新建一个类，放到同一个包下，最后的目录结构如下：
圈出来的三个类都是需要的依赖类
第二步：
新建接口PathMatcher的实现类，重写math方法：
import org.springframework.util.AntPathMatcher; import org.springframework.util.Assert; import org.springframework.util.PathMatcher; import org.springframework.util.StringUtils; import java.util.*; import java.util.concurrent.ConcurrentHashMap; import java.util.regex.Matcher; import java.util.regex.Pattern; public class RePathMatcher extends AntPathMatcher implements PathMatcher { @Override public boolean match(String pattern, String path) { if(super.match(pattern,path )){ return true; } else { pattern = pattern.replaceAll("\\*\\*","(.*)" ); Pattern rePattern = Pattern.compile(pattern); Matcher matcher = rePattern.matcher(path); if (matcher.matches()) { return true; } return false; } } }
说明：先调用父类AntPathMatcher中的match方法，如果匹配到了就返回true，如果没有匹配到，就走正则，这里面需要先把pattern中的**替换成正则表达式，因为在配置的转发规则都是下面这样的形式：
| path | host |
| /tech/** | http://tech.com |
如果不替换，**无法被识别会抛异常。替换后就是正常的正则匹配了。
第三步：
使用反射修改ZuulHandlerMapping中的pathMatcher属性。
修改我们新建的配置类CusZuulServerAutoConfiguration中ZuulHandlerMapping注入的代码：
@Bean public ZuulHandlerMapping zuulHandlerMapping(RouteLocator routes) { ZuulHandlerMapping mapping = new ZuulHandlerMapping(routes, zuulController()); try { Class<?> clazz = Class.forName("org.springframework.cloud.netflix.zuul.web.ZuulHandlerMapping"); Field[] fs = clazz.getDeclaredFields(); for (Field field : fs) { field.setAccessible(true); if(field.getName().equals("pathMatcher")){ field.set(mapping, new RePathMatcher()); } } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } mapping.setErrorController(this.errorController); return mapping; }
第四步：在SpringbootApplication中屏蔽ZuulProxyAutoConfiguration
@SpringBootApplication(exclude = ZuulProxyAutoConfiguration.class)
另外两个自定义的配置类需要修改：
@ConditionalOnBean(ZuulProxyMarkerConfiguration.Marker.class)
//替换成：
@ConditionalOnBean(annotation=EnableZuulProxy.class)
@ConditionalOnBean(ZuulServerMarkerConfiguration.Marker.class)
替换成
@ConditionalOnBean(annotation=EnableZuulProxy.class)
PS：目前想到的方式就是这样，如果大家有好的方式，欢迎留言。
