淺談SpringCloud之zuul源碼解析
zuul各版本實(shí)現(xiàn)存在一些微小的變化,總的實(shí)現(xiàn)思想未改變,以spring-cloud-netflix-core-1.3.6.RELEASE為例
一、zuul的重要的初始化類
org.springframework.cloud.netflix.zuul.ZuulServerAutoConfiguration
org.springframework.cloud.netflix.zuul.ZuulProxyAutoConfiguration
org.springframework.cloud.netflix.zuul.ZuulFilterInitializer
org.springframework.cloud.netflix.zuul.RibbonCommandFactoryConfiguration
ZuulServerAutoConfiguration
初始化路由規(guī)則
初始化一些重要的filter如 PreDecorationFilter,RibbonRoutingFilter
初始化ZuulFilterInitializer
初始化ZuulHandlerMapping
代碼如下
//路由規(guī)則 @Bean @ConditionalOnMissingBean(DiscoveryClientRouteLocator.class) public DiscoveryClientRouteLocator discoveryRouteLocator() { return new DiscoveryClientRouteLocator(this.server.getServletPrefix(), this.discovery, this.zuulProperties, this.serviceRouteMapper); } // pre filters @Bean public PreDecorationFilter preDecorationFilter(RouteLocator routeLocator, ProxyRequestHelper proxyRequestHelper) { return new PreDecorationFilter(routeLocator, this.server.getServletPrefix(), this.zuulProperties, proxyRequestHelper); } // route filters @Bean public RibbonRoutingFilter ribbonRoutingFilter(ProxyRequestHelper helper, RibbonCommandFactory<?> ribbonCommandFactory) { RibbonRoutingFilter filter = new RibbonRoutingFilter(helper, ribbonCommandFactory, this.requestCustomizers); return filter; } @Configuration protected static class ZuulFilterConfiguration { @Autowired private Map<String, ZuulFilter> filters; @Bean public ZuulFilterInitializer zuulFilterInitializer( CounterFactory counterFactory, TracerFactory tracerFactory) { FilterLoader filterLoader = FilterLoader.getInstance(); FilterRegistry filterRegistry = FilterRegistry.instance(); return new ZuulFilterInitializer(this.filters, counterFactory, tracerFactory, filterLoader, filterRegistry); } } @Bean public ZuulController zuulController() { return new ZuulController(); } @Bean public ZuulHandlerMapping zuulHandlerMapping(RouteLocator routes) { ZuulHandlerMapping mapping = new ZuulHandlerMapping(routes, zuulController()); mapping.setErrorController(this.errorController); return mapping; }
ZuulProxyAutoConfiguration
zuulProxAutoConfiguration繼承ZuulServerAutoConfiguration功能上和zuulServerAutoConfiguration
主要功能是增加了RibbonCommandFactoryConfiguration的配置,初始化所有的實(shí)現(xiàn)ribbon的方式如apache,okhttp。
ZuulFilterInitializer
該類的作用主要是把初始化的過(guò)濾器注冊(cè)到zuul的FilterRegistry,F(xiàn)ilterRegistry是一個(gè)單例用于初始化路由信息,在ZuulRunner中使用
RibbonCommandFactoryConfiguration
主要作用是配置轉(zhuǎn)發(fā)的實(shí)現(xiàn),實(shí)現(xiàn)主要有apache,okhttp
二、zuul的轉(zhuǎn)發(fā)實(shí)現(xiàn)
首先第一步轉(zhuǎn)到ZuulHandlerMapping中的lookupHandler方法,把轉(zhuǎn)發(fā)轉(zhuǎn)到zuulController中
@Override protected Object lookupHandler(String urlPath, HttpServletRequest request) throws Exception { if (this.errorController != null && urlPath.equals(this.errorController.getErrorPath())) { return null; } String[] ignored = this.routeLocator.getIgnoredPaths().toArray(new String[0]); if (PatternMatchUtils.simpleMatch(ignored, urlPath)) { 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); }
第一次訪問(wèn)時(shí)dirty為true會(huì)初始化一次請(qǐng)求規(guī)則如下
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); } } }
第二步ZuulController繼承ServletWrappingController的會(huì)把請(qǐng)求轉(zhuǎn)到ZuulServlet中如下
/** * @author Spencer Gibb */ public class ZuulController extends ServletWrappingController { public ZuulController() { setServletClass(ZuulServlet.class); setServletName("zuul"); setSupportedMethods((String[]) null); // Allow all } @Override public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception { try { // We don't care about the other features of the base class, just want to // handle the request return super.handleRequestInternal(request, response); } finally { // @see com.netflix.zuul.context.ContextLifecycleFilter.doFilter RequestContext.getCurrentContext().unset(); } } }
第三步ZuulServlet的service方法如下主要執(zhí)行pre,route,postRoute三種路由器
@Override public void service(javax.servlet.ServletRequest servletRequest, javax.servlet.ServletResponse servletResponse) throws ServletException, IOException { try { init((HttpServletRequest) servletRequest, (HttpServletResponse) servletResponse); // Marks this request as having passed through the "Zuul engine", as opposed to servlets // explicitly bound in web.xml, for which requests will not have the same data attached RequestContext context = RequestContext.getCurrentContext(); context.setZuulEngineRan(); try { preRoute(); } catch (ZuulException e) { error(e); postRoute(); return; } try { route(); } catch (ZuulException e) { error(e); postRoute(); return; } try { postRoute(); } catch (ZuulException e) { error(e); return; } } catch (Throwable e) { error(new ZuulException(e, 500, "UNHANDLED_EXCEPTION_" + e.getClass().getName())); } finally { RequestContext.getCurrentContext().unset(); } }
四、最后由SendResponseFilter執(zhí)行返回結(jié)果,filterOrder為1000所以最好post的filter不要超過(guò)1000否則影響返回結(jié)果
以上就是本文的全部?jī)?nèi)容,希望對(duì)大家的學(xué)習(xí)有所幫助,也希望大家多多支持腳本之家。
相關(guān)文章
Java實(shí)現(xiàn)平鋪列表(List)互轉(zhuǎn)樹(shù)形(Tree)結(jié)構(gòu)
本文主要介紹了Java實(shí)現(xiàn)平鋪列表(List)互轉(zhuǎn)樹(shù)形(Tree)結(jié)構(gòu),文中通過(guò)示例代碼介紹的非常詳細(xì),對(duì)大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價(jià)值,需要的朋友們下面隨著小編來(lái)一起學(xué)習(xí)學(xué)習(xí)吧2022-08-08Java concurrency之CountDownLatch原理和示例_動(dòng)力節(jié)點(diǎn)Java學(xué)院整理
CountDownLatch是一個(gè)同步輔助類,在完成一組正在其他線程中執(zhí)行的操作之前,它允許一個(gè)或多個(gè)線程一直等待。 下面通過(guò)本文給大家分享Java concurrency之CountDownLatch原理和示例,需要的的朋友參考下吧2017-06-06詳解java中finalize的實(shí)現(xiàn)與相應(yīng)的執(zhí)行過(guò)程
在常規(guī)的java書(shū)籍中,即會(huì)描述 object的finalize方法是用于一些特殊的對(duì)象在回收之前再做一些掃尾的工作,但是并沒(méi)有說(shuō)明此是如何實(shí)現(xiàn)的.本篇從java的角度(不涉及jvm以及c++),有需要的朋友們可以參考借鑒。2016-09-09Java數(shù)據(jù)結(jié)構(gòu)之HashMap和HashSet
這篇文章主要介紹了HashMap和HashSet,什么是哈希表以及HashMap的部分源碼解讀,想了解更多的小伙伴,可以參考閱讀本文2023-03-03如何在Spring Boot中實(shí)現(xiàn)異步處理與并發(fā)控制
本文我們將深入探討如何在Spring Boot中實(shí)現(xiàn)異步處理與并發(fā)控制,這一過(guò)程涉及到異步任務(wù)的執(zhí)行、線程池的配置、以及并發(fā)控制的實(shí)踐,以幫助我們提升應(yīng)用的性能和響應(yīng)能力,感興趣的朋友跟隨小編一起看看吧2024-07-07實(shí)現(xiàn)quartz定時(shí)器及quartz定時(shí)器原理介紹
Quartz是一個(gè)大名鼎鼎的Java版開(kāi)源定時(shí)調(diào)度器,功能強(qiáng)悍,使用方便,下面我們看看如何使用它2013-12-12深入分析:用1K內(nèi)存實(shí)現(xiàn)高效I/O的RandomAccessFile類的詳解
本篇文章是對(duì)用1K內(nèi)存實(shí)現(xiàn)高效I/O的RandomAccessFile類的詳細(xì)分析介紹,需要的朋友參考下2013-05-05聊聊Arrays.deepToString()和Arrays.toString()的區(qū)別
這篇文章主要介紹了聊聊Arrays.deepToString()和Arrays.toString()的區(qū)別,具有很好的參考價(jià)值,希望對(duì)大家有所幫助。一起跟隨小編過(guò)來(lái)看看吧2021-02-02