diff --git a/docs/SpringCloud/spring-cloud-gateway-source-note.md b/docs/SpringCloud/spring-cloud-gateway-source-note.md index 35813ee..9727836 100644 --- a/docs/SpringCloud/spring-cloud-gateway-source-note.md +++ b/docs/SpringCloud/spring-cloud-gateway-source-note.md @@ -77,18 +77,18 @@ org.springframework.cloud.gateway.mvc.config.ProxyResponseAutoConfiguration @ConditionalOnProperty(name = "spring.cloud.gateway.enabled", matchIfMissing = true) public class GatewayClassPathWarningAutoConfiguration { - @Configuration(proxyBeanMethods = false) + @Configuration(proxyBeanMethods = false) // SpringMVC 会存在这个类，所以条件会满足，这个类就会注册到BeanFactory中 - @ConditionalOnClass(name = "org.springframework.web.servlet.DispatcherServlet") - @ConditionalOnWebApplication(type = ConditionalOnWebApplication.Type.SERVLET) - protected static class SpringMvcFoundOnClasspathConfiguration { + @ConditionalOnClass(name = "org.springframework.web.servlet.DispatcherServlet") + @ConditionalOnWebApplication(type = ConditionalOnWebApplication.Type.SERVLET) + protected static class SpringMvcFoundOnClasspathConfiguration { - public SpringMvcFoundOnClasspathConfiguration() { - // 实例化就直接抛出异常 - throw new MvcFoundOnClasspathException(); - } + public SpringMvcFoundOnClasspathConfiguration() { + // 实例化就直接抛出异常 + throw new MvcFoundOnClasspathException(); + } - } + } } ``` @@ -272,34 +272,34 @@ public class GatewayAutoConfiguration { @Configuration(proxyBeanMethods = false) @ConditionalOnProperty(name = "spring.cloud.gateway.enabled", matchIfMissing = true) @ConditionalOnClass({ DispatcherHandler.class, ReactiveResilience4JAutoConfiguration.class, - ReactiveCircuitBreakerFactory.class, ReactiveResilience4JCircuitBreakerFactory.class }) + ReactiveCircuitBreakerFactory.class, ReactiveResilience4JCircuitBreakerFactory.class }) public class GatewayResilience4JCircuitBreakerAutoConfiguration { - /** - * SpringCloudCircuitBreakerResilience4JFilterFactory 实现 GatewayFilterFactory 接口， - * 其核心逻辑是使用 ReactiveCircuitBreaker 来执行业务逻辑，当 出现异常 或者 路由请求返回的状态码是期望值 就 - * 直接使用 DispatcherHandler 来执行 fallbackUrl，可以理解成使用 fallbackUrl 重新执行一次请求。 - * 并且会往 ServerWebExchange 设置一个key记录异常对象。 - */ - @Bean - @ConditionalOnBean(ReactiveResilience4JCircuitBreakerFactory.class) - @ConditionalOnEnabledFilter - public SpringCloudCircuitBreakerResilience4JFilterFactory springCloudCircuitBreakerResilience4JFilterFactory( - ReactiveResilience4JCircuitBreakerFactory reactiveCircuitBreakerFactory, - ObjectProvider dispatcherHandler) { - return new SpringCloudCircuitBreakerResilience4JFilterFactory(reactiveCircuitBreakerFactory, dispatcherHandler); - } - - /** - * FallbackHeadersGatewayFilterFactory 实现 GatewayFilterFactory 接口， - * 其核心逻辑：如果请求是 fallbackUrl 执行的（通过异常key判断），那就设置一些请求头 - */ - @Bean - @ConditionalOnMissingBean - @ConditionalOnEnabledFilter - public FallbackHeadersGatewayFilterFactory fallbackHeadersGatewayFilterFactory() { - return new FallbackHeadersGatewayFilterFactory(); - } + /** + * SpringCloudCircuitBreakerResilience4JFilterFactory 实现 GatewayFilterFactory 接口， + * 其核心逻辑是使用 ReactiveCircuitBreaker 来执行业务逻辑，当 出现异常 或者 路由请求返回的状态码是期望值 就 + * 直接使用 DispatcherHandler 来执行 fallbackUrl，可以理解成使用 fallbackUrl 重新执行一次请求。 + * 并且会往 ServerWebExchange 设置一个key记录异常对象。 + */ + @Bean + @ConditionalOnBean(ReactiveResilience4JCircuitBreakerFactory.class) + @ConditionalOnEnabledFilter + public SpringCloudCircuitBreakerResilience4JFilterFactory springCloudCircuitBreakerResilience4JFilterFactory( + ReactiveResilience4JCircuitBreakerFactory reactiveCircuitBreakerFactory, + ObjectProvider dispatcherHandler) { + return new SpringCloudCircuitBreakerResilience4JFilterFactory(reactiveCircuitBreakerFactory, dispatcherHandler); + } + + /** + * FallbackHeadersGatewayFilterFactory 实现 GatewayFilterFactory 接口， + * 其核心逻辑：如果请求是 fallbackUrl 执行的（通过异常key判断），那就设置一些请求头 + */ + @Bean + @ConditionalOnMissingBean + @ConditionalOnEnabledFilter + public FallbackHeadersGatewayFilterFactory fallbackHeadersGatewayFilterFactory() { + return new FallbackHeadersGatewayFilterFactory(); + } } ``` @@ -314,45 +314,45 @@ public class GatewayResilience4JCircuitBreakerAutoConfiguration { @AutoConfigureAfter(GatewayReactiveLoadBalancerClientAutoConfiguration.class) public class GatewayNoLoadBalancerClientAutoConfiguration { - /** - * NoLoadBalancerClientFilter 实现 GlobalFilter 接口，也就是每个 Route 的请求都会执行。 - * 功能：路由的Url 有 lb 前缀 就直接抛出异常，也就是说不支持 负载均衡的路由 - * - * BeanFactory 中没有 ReactiveLoadBalancerClientFilter 才会生效。 - */ - @Bean - @ConditionalOnMissingBean(ReactiveLoadBalancerClientFilter.class) - public NoLoadBalancerClientFilter noLoadBalancerClientFilter(GatewayLoadBalancerProperties properties) { - return new NoLoadBalancerClientFilter(properties.isUse404()); - } - - protected static class NoLoadBalancerClientFilter implements GlobalFilter, Ordered { - - private final boolean use404; - - public NoLoadBalancerClientFilter(boolean use404) { - this.use404 = use404; - } - - @Override - public int getOrder() { - return LOAD_BALANCER_CLIENT_FILTER_ORDER; - } - - @Override - @SuppressWarnings("Duplicates") - public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { - URI url = exchange.getAttribute(GATEWAY_REQUEST_URL_ATTR); - String schemePrefix = exchange.getAttribute(GATEWAY_SCHEME_PREFIX_ATTR); - // url 没有 lb 前缀 就放行 - if (url == null || (!"lb".equals(url.getScheme()) && !"lb".equals(schemePrefix))) { - return chain.filter(exchange); - } - // 不能处理 lb:// 所以 直接报错 - throw NotFoundException.create(use404, "Unable to find instance for " + url.getHost()); - } + /** + * NoLoadBalancerClientFilter 实现 GlobalFilter 接口，也就是每个 Route 的请求都会执行。 + * 功能：路由的Url 有 lb 前缀 就直接抛出异常，也就是说不支持 负载均衡的路由 + * + * BeanFactory 中没有 ReactiveLoadBalancerClientFilter 才会生效。 + */ + @Bean + @ConditionalOnMissingBean(ReactiveLoadBalancerClientFilter.class) + public NoLoadBalancerClientFilter noLoadBalancerClientFilter(GatewayLoadBalancerProperties properties) { + return new NoLoadBalancerClientFilter(properties.isUse404()); + } + + protected static class NoLoadBalancerClientFilter implements GlobalFilter, Ordered { + + private final boolean use404; - } + public NoLoadBalancerClientFilter(boolean use404) { + this.use404 = use404; + } + + @Override + public int getOrder() { + return LOAD_BALANCER_CLIENT_FILTER_ORDER; + } + + @Override + @SuppressWarnings("Duplicates") + public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { + URI url = exchange.getAttribute(GATEWAY_REQUEST_URL_ATTR); + String schemePrefix = exchange.getAttribute(GATEWAY_SCHEME_PREFIX_ATTR); + // url 没有 lb 前缀 就放行 + if (url == null || (!"lb".equals(url.getScheme()) && !"lb".equals(schemePrefix))) { + return chain.filter(exchange); + } + // 不能处理 lb:// 所以 直接报错 + throw NotFoundException.create(use404, "Unable to find instance for " + url.getHost()); + } + + } } ``` @@ -366,54 +366,54 @@ public class GatewayNoLoadBalancerClientAutoConfiguration { @ConditionalOnClass({ DispatcherHandler.class, MeterRegistry.class, MetricsAutoConfiguration.class }) public class GatewayMetricsAutoConfiguration { - // 会从 ServerWebExchange 中得到 请求的Method、响应的状态码等 - @Bean - public GatewayHttpTagsProvider gatewayHttpTagsProvider() { - return new GatewayHttpTagsProvider(); - } - - // 会从 ServerWebExchange 中得到 匹配的路由地址 - @Bean - @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.tags.path.enabled") - public GatewayPathTagsProvider gatewayPathTagsProvider() { - return new GatewayPathTagsProvider(); - } - - // 会从 ServerWebExchange 中得到 routId、route uri - @Bean - public GatewayRouteTagsProvider gatewayRouteTagsProvider() { - return new GatewayRouteTagsProvider(); - } - - // 将 GatewayMetricsProperties 的信息映射成 Tags - @Bean - public PropertiesTagsProvider propertiesTagsProvider(GatewayMetricsProperties properties) { - return new PropertiesTagsProvider(properties.getTags()); - } - - /** - * GatewayMetricsFilter 实现 GlobalFilter 接口， - * 将 List 返回的信息记录到 MeterRegistry 中 - */ - @Bean - @ConditionalOnBean(MeterRegistry.class) - @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.enabled", matchIfMissing = true) - public GatewayMetricsFilter gatewayMetricFilter(MeterRegistry meterRegistry, - List tagsProviders, GatewayMetricsProperties properties) { - return new GatewayMetricsFilter(meterRegistry, tagsProviders, properties.getPrefix()); - } - - /** - * RouteDefinitionMetrics 实现 ApplicationListener 接口， - * 收到事件的逻辑是 RouteDefinitionLocator.getRouteDefinitions().count() 记录到 MeterRegistry 中 - */ - @Bean - @ConditionalOnBean(MeterRegistry.class) - @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.enabled", matchIfMissing = true) - public RouteDefinitionMetrics routeDefinitionMetrics(MeterRegistry meterRegistry, - RouteDefinitionLocator routeDefinitionLocator, GatewayMetricsProperties properties) { - return new RouteDefinitionMetrics(meterRegistry, routeDefinitionLocator, properties.getPrefix()); - } + // 会从 ServerWebExchange 中得到 请求的Method、响应的状态码等 + @Bean + public GatewayHttpTagsProvider gatewayHttpTagsProvider() { + return new GatewayHttpTagsProvider(); + } + + // 会从 ServerWebExchange 中得到 匹配的路由地址 + @Bean + @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.tags.path.enabled") + public GatewayPathTagsProvider gatewayPathTagsProvider() { + return new GatewayPathTagsProvider(); + } + + // 会从 ServerWebExchange 中得到 routId、route uri + @Bean + public GatewayRouteTagsProvider gatewayRouteTagsProvider() { + return new GatewayRouteTagsProvider(); + } + + // 将 GatewayMetricsProperties 的信息映射成 Tags + @Bean + public PropertiesTagsProvider propertiesTagsProvider(GatewayMetricsProperties properties) { + return new PropertiesTagsProvider(properties.getTags()); + } + + /** + * GatewayMetricsFilter 实现 GlobalFilter 接口， + * 将 List 返回的信息记录到 MeterRegistry 中 + */ + @Bean + @ConditionalOnBean(MeterRegistry.class) + @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.enabled", matchIfMissing = true) + public GatewayMetricsFilter gatewayMetricFilter(MeterRegistry meterRegistry, + List tagsProviders, GatewayMetricsProperties properties) { + return new GatewayMetricsFilter(meterRegistry, tagsProviders, properties.getPrefix()); + } + + /** + * RouteDefinitionMetrics 实现 ApplicationListener 接口， + * 收到事件的逻辑是 RouteDefinitionLocator.getRouteDefinitions().count() 记录到 MeterRegistry 中 + */ + @Bean + @ConditionalOnBean(MeterRegistry.class) + @ConditionalOnProperty(name = GatewayProperties.PREFIX + ".metrics.enabled", matchIfMissing = true) + public RouteDefinitionMetrics routeDefinitionMetrics(MeterRegistry meterRegistry, + RouteDefinitionLocator routeDefinitionLocator, GatewayMetricsProperties properties) { + return new RouteDefinitionMetrics(meterRegistry, routeDefinitionLocator, properties.getPrefix()); + } } ``` @@ -427,20 +427,20 @@ public class GatewayMetricsAutoConfiguration { @ConditionalOnProperty(name = "spring.cloud.gateway.redis.enabled", matchIfMissing = true) class GatewayRedisAutoConfiguration { - /** - * RedisRouteDefinitionRepository 实现 RouteDefinitionRepository 接口。 - * 使用 redis 作为缓存层，存储 RouteDefinition - */ - @Bean - @ConditionalOnProperty(value = "spring.cloud.gateway.redis-route-definition-repository.enabled", - havingValue = "true") - @ConditionalOnClass(ReactiveRedisTemplate.class) - public RedisRouteDefinitionRepository redisRouteDefinitionRepository( - ReactiveRedisTemplate reactiveRedisTemplate) { - return new RedisRouteDefinitionRepository(reactiveRedisTemplate); - } - - // ... + /** + * RedisRouteDefinitionRepository 实现 RouteDefinitionRepository 接口。 + * 使用 redis 作为缓存层，存储 RouteDefinition + */ + @Bean + @ConditionalOnProperty(value = "spring.cloud.gateway.redis-route-definition-repository.enabled", + havingValue = "true") + @ConditionalOnClass(ReactiveRedisTemplate.class) + public RedisRouteDefinitionRepository redisRouteDefinitionRepository( + ReactiveRedisTemplate reactiveRedisTemplate) { + return new RedisRouteDefinitionRepository(reactiveRedisTemplate); + } + + // ... } ``` @@ -453,79 +453,79 @@ class GatewayRedisAutoConfiguration { @EnableConfigurationProperties public class GatewayDiscoveryClientAutoConfiguration { - /** - * 这是一个 PathRoutePredicateFactory，根据 serviceId 进行路由 - * @return - */ - public static List initPredicates() { - ArrayList definitions = new ArrayList<>(); - // TODO: add a predicate that matches the url at /serviceId? - - // add a predicate that matches the url at /serviceId/** - PredicateDefinition predicate = new PredicateDefinition(); - predicate.setName(normalizeRoutePredicateName(PathRoutePredicateFactory.class)); - predicate.addArg(PATTERN_KEY, "'/'+serviceId+'/**'"); - definitions.add(predicate); - return definitions; - } - - /** - * 这是一个 RewritePathGatewayFilterFactory，移除 serviceId 路径前缀 - * @return - */ - public static List initFilters() { - ArrayList definitions = new ArrayList<>(); - - // add a filter that removes /serviceId by default - FilterDefinition filter = new FilterDefinition(); - filter.setName(normalizeFilterFactoryName(RewritePathGatewayFilterFactory.class)); - String regex = "'/' + serviceId + '/?(?.*)'"; - String replacement = "'/${remaining}'"; - filter.addArg(REGEXP_KEY, regex); - filter.addArg(REPLACEMENT_KEY, replacement); - definitions.add(filter); - - return definitions; - } - - /** - * DiscoveryLocatorProperties 类上标注了 @ConfigurationProperties("spring.cloud.gateway.discovery.locator") - * 也就是可以通过配置属性的方式设置属性值，下面的逻辑是设置默认值的意思。 - * DiscoveryClientRouteDefinitionLocator 会使用这两个属性会作为生成 RouteDefinition 的 Predicate 和 Filter - * @return - */ - @Bean - public DiscoveryLocatorProperties discoveryLocatorProperties() { - DiscoveryLocatorProperties properties = new DiscoveryLocatorProperties(); - // 默认就设置 PathRoutePredicateFactory - properties.setPredicates(initPredicates()); - // 默认就设置 RewritePathGatewayFilterFactory - properties.setFilters(initFilters()); - return properties; - } - - @Configuration(proxyBeanMethods = false) - @ConditionalOnProperty(value = "spring.cloud.discovery.reactive.enabled", matchIfMissing = true) - public static class ReactiveDiscoveryClientRouteDefinitionLocatorConfiguration { - - /** - * DiscoveryClientRouteDefinitionLocator 实现 RouteDefinitionLocator。 - * 会根据 ReactiveDiscoveryClient.getServices() 返回的 Flux 生成 Flux - * 每个 RouteDefinition 是由 ServiceInstance + DiscoveryLocatorProperties 的内容 配置 路由Uri、Predicate、Filter - * 大部分属性值是通过解析 SPEL 表达式得到的，其中根对象是 ServiceInstance，所以说 编写的 SPEL 表达式可以引用 ServiceInstance 中的属性 - * - * @param discoveryClient - * @param properties - * @return - */ - @Bean - @ConditionalOnProperty(name = "spring.cloud.gateway.discovery.locator.enabled") - public DiscoveryClientRouteDefinitionLocator discoveryClientRouteDefinitionLocator( - ReactiveDiscoveryClient discoveryClient, DiscoveryLocatorProperties properties) { - return new DiscoveryClientRouteDefinitionLocator(discoveryClient, properties); - } - - } + /** + * 这是一个 PathRoutePredicateFactory，根据 serviceId 进行路由 + * @return + */ + public static List initPredicates() { + ArrayList definitions = new ArrayList<>(); + // TODO: add a predicate that matches the url at /serviceId? + + // add a predicate that matches the url at /serviceId/** + PredicateDefinition predicate = new PredicateDefinition(); + predicate.setName(normalizeRoutePredicateName(PathRoutePredicateFactory.class)); + predicate.addArg(PATTERN_KEY, "'/'+serviceId+'/**'"); + definitions.add(predicate); + return definitions; + } + + /** + * 这是一个 RewritePathGatewayFilterFactory，移除 serviceId 路径前缀 + * @return + */ + public static List initFilters() { + ArrayList definitions = new ArrayList<>(); + + // add a filter that removes /serviceId by default + FilterDefinition filter = new FilterDefinition(); + filter.setName(normalizeFilterFactoryName(RewritePathGatewayFilterFactory.class)); + String regex = "'/' + serviceId + '/?(?.*)'"; + String replacement = "'/${remaining}'"; + filter.addArg(REGEXP_KEY, regex); + filter.addArg(REPLACEMENT_KEY, replacement); + definitions.add(filter); + + return definitions; + } + + /** + * DiscoveryLocatorProperties 类上标注了 @ConfigurationProperties("spring.cloud.gateway.discovery.locator") + * 也就是可以通过配置属性的方式设置属性值，下面的逻辑是设置默认值的意思。 + * DiscoveryClientRouteDefinitionLocator 会使用这两个属性会作为生成 RouteDefinition 的 Predicate 和 Filter + * @return + */ + @Bean + public DiscoveryLocatorProperties discoveryLocatorProperties() { + DiscoveryLocatorProperties properties = new DiscoveryLocatorProperties(); + // 默认就设置 PathRoutePredicateFactory + properties.setPredicates(initPredicates()); + // 默认就设置 RewritePathGatewayFilterFactory + properties.setFilters(initFilters()); + return properties; + } + + @Configuration(proxyBeanMethods = false) + @ConditionalOnProperty(value = "spring.cloud.discovery.reactive.enabled", matchIfMissing = true) + public static class ReactiveDiscoveryClientRouteDefinitionLocatorConfiguration { + + /** + * DiscoveryClientRouteDefinitionLocator 实现 RouteDefinitionLocator。 + * 会根据 ReactiveDiscoveryClient.getServices() 返回的 Flux 生成 Flux + * 每个 RouteDefinition 是由 ServiceInstance + DiscoveryLocatorProperties 的内容 配置 路由Uri、Predicate、Filter + * 大部分属性值是通过解析 SPEL 表达式得到的，其中根对象是 ServiceInstance，所以说 编写的 SPEL 表达式可以引用 ServiceInstance 中的属性 + * + * @param discoveryClient + * @param properties + * @return + */ + @Bean + @ConditionalOnProperty(name = "spring.cloud.gateway.discovery.locator.enabled") + public DiscoveryClientRouteDefinitionLocator discoveryClientRouteDefinitionLocator( + ReactiveDiscoveryClient discoveryClient, DiscoveryLocatorProperties properties) { + return new DiscoveryClientRouteDefinitionLocator(discoveryClient, properties); + } + + } } ``` @@ -536,22 +536,22 @@ public class GatewayDiscoveryClientAutoConfiguration { @Configuration(proxyBeanMethods = false) @ConditionalOnClass(SimpleUrlHandlerMapping.class) @ConditionalOnProperty(name = "spring.cloud.gateway.globalcors.add-to-simple-url-handler-mapping", - matchIfMissing = false) + matchIfMissing = false) public class SimpleUrlHandlerMappingGlobalCorsAutoConfiguration { - @Autowired - private GlobalCorsProperties globalCorsProperties; + @Autowired + private GlobalCorsProperties globalCorsProperties; - @Autowired - private SimpleUrlHandlerMapping simpleUrlHandlerMapping; + @Autowired + private SimpleUrlHandlerMapping simpleUrlHandlerMapping; - /** - * 为 SimpleUrlHandlerMapping 配置 跨域配置信息 - */ - @PostConstruct - void config() { - simpleUrlHandlerMapping.setCorsConfigurations(globalCorsProperties.getCorsConfigurations()); - } + /** + * 为 SimpleUrlHandlerMapping 配置 跨域配置信息 + */ + @PostConstruct + void config() { + simpleUrlHandlerMapping.setCorsConfigurations(globalCorsProperties.getCorsConfigurations()); + } } ``` @@ -564,31 +564,31 @@ public class SimpleUrlHandlerMappingGlobalCorsAutoConfiguration { @EnableConfigurationProperties(GatewayLoadBalancerProperties.class) public class GatewayReactiveLoadBalancerClientAutoConfiguration { - /** - * ReactiveLoadBalancerClientFilter 实现 GlobalFilter 接口。 - * 作用：url 没有 lb 协议 就放行，有 lb 就使用 LoadBalancerClientFactory 得到负载均衡后的 uri，修改 ServerWebExchange 放行filter - */ - @Bean - @ConditionalOnBean(LoadBalancerClientFactory.class) - @ConditionalOnMissingBean(ReactiveLoadBalancerClientFilter.class) - @ConditionalOnEnabledGlobalFilter - public ReactiveLoadBalancerClientFilter gatewayLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, - GatewayLoadBalancerProperties properties) { - return new ReactiveLoadBalancerClientFilter(clientFactory, properties); - } - - /** - * LoadBalancerServiceInstanceCookieFilter 实现 GlobalFilter 接口 - * 作用：是负载均衡的路由，就添加一个Cookie键值对 - */ - @Bean - @ConditionalOnBean({ ReactiveLoadBalancerClientFilter.class, LoadBalancerClientFactory.class }) - @ConditionalOnMissingBean - @ConditionalOnEnabledGlobalFilter - public LoadBalancerServiceInstanceCookieFilter loadBalancerServiceInstanceCookieFilter( - LoadBalancerClientFactory loadBalancerClientFactory) { - return new LoadBalancerServiceInstanceCookieFilter(loadBalancerClientFactory); - } + /** + * ReactiveLoadBalancerClientFilter 实现 GlobalFilter 接口。 + * 作用：url 没有 lb 协议 就放行，有 lb 就使用 LoadBalancerClientFactory 得到负载均衡后的 uri，修改 ServerWebExchange 放行filter + */ + @Bean + @ConditionalOnBean(LoadBalancerClientFactory.class) + @ConditionalOnMissingBean(ReactiveLoadBalancerClientFilter.class) + @ConditionalOnEnabledGlobalFilter + public ReactiveLoadBalancerClientFilter gatewayLoadBalancerClientFilter(LoadBalancerClientFactory clientFactory, + GatewayLoadBalancerProperties properties) { + return new ReactiveLoadBalancerClientFilter(clientFactory, properties); + } + + /** + * LoadBalancerServiceInstanceCookieFilter 实现 GlobalFilter 接口 + * 作用：是负载均衡的路由，就添加一个Cookie键值对 + */ + @Bean + @ConditionalOnBean({ ReactiveLoadBalancerClientFilter.class, LoadBalancerClientFactory.class }) + @ConditionalOnMissingBean + @ConditionalOnEnabledGlobalFilter + public LoadBalancerServiceInstanceCookieFilter loadBalancerServiceInstanceCookieFilter( + LoadBalancerClientFactory loadBalancerClientFactory) { + return new LoadBalancerServiceInstanceCookieFilter(loadBalancerClientFactory); + } } ``` @@ -615,19 +615,19 @@ ProxyResponseAutoConfiguration 是 HandlerMethodArgumentResolver 接口的实现 @Retention(RetentionPolicy.RUNTIME)@Target({ ElementType.TYPE, ElementType.METHOD }) @Conditional(OnEnabledGlobalFilter.class) public @interface ConditionalOnEnabledGlobalFilter { - Class value() default OnEnabledGlobalFilter.DefaultValue.class; + Class value() default OnEnabledGlobalFilter.DefaultValue.class; } @Retention(RetentionPolicy.RUNTIME)@Target({ ElementType.TYPE, ElementType.METHOD }) @Conditional(OnEnabledFilter.class) public @interface ConditionalOnEnabledFilter { - Class> value() default OnEnabledFilter.DefaultValue.class; + Class> value() default OnEnabledFilter.DefaultValue.class; } @Retention(RetentionPolicy.RUNTIME)@Target({ ElementType.TYPE, ElementType.METHOD }) @Conditional(OnEnabledPredicate.class) public @interface ConditionalOnEnabledPredicate { - Class> value() default OnEnabledPredicate.DefaultValue.class; + Class> value() default OnEnabledPredicate.DefaultValue.class; } ``` @@ -667,40 +667,40 @@ spring.cloud.gateway.predicate.XX.enabled=false ```java public class NettyRoutingFilter implements GlobalFilter, Ordered { - @Override - public int getOrder() { - return Integer.MAX_VALUE; // 最大值，说明这是最后要执行的 GatewayFilter - } - - @Override - @SuppressWarnings("Duplicates") - public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { - URI requestUrl = exchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR); - - String scheme = requestUrl.getScheme(); - // 已经路由 或者 不是 http、https 就放行 - if (isAlreadyRouted(exchange) || (!"http".equalsIgnoreCase(scheme) && !"https".equalsIgnoreCase(scheme))) { - return chain.filter(exchange); - } - // 设置一个属性，标记 已经路由了 - setAlreadyRouted(exchange); - - /** - * 遍历执行所有的 HttpHeadersFilter 得到 HttpHeaders。 - * 也就是说可以对最终要执行的 请求头 进行加工 - * - * 注：HttpHeadersFilter 是从BeanFactory中获取的，所以我们可以自定义 HttpHeadersFilter 达到扩展的目的 - * */ - HttpHeaders filtered = filterRequest(getHeadersFilters(), exchange); - - // 根据 Route 的元数据构造 HttpClient 然后执行请求 - Flux responseFlux = getHttpClient(route, exchange) - .headers() - .responseConnection((res, connection) -> {}); - - // 放行 - return responseFlux.then(chain.filter(exchange)); - } + @Override + public int getOrder() { + return Integer.MAX_VALUE; // 最大值，说明这是最后要执行的 GatewayFilter + } + + @Override + @SuppressWarnings("Duplicates") + public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { + URI requestUrl = exchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR); + + String scheme = requestUrl.getScheme(); + // 已经路由 或者 不是 http、https 就放行 + if (isAlreadyRouted(exchange) || (!"http".equalsIgnoreCase(scheme) && !"https".equalsIgnoreCase(scheme))) { + return chain.filter(exchange); + } + // 设置一个属性，标记 已经路由了 + setAlreadyRouted(exchange); + + /** + * 遍历执行所有的 HttpHeadersFilter 得到 HttpHeaders。 + * 也就是说可以对最终要执行的 请求头 进行加工 + * + * 注：HttpHeadersFilter 是从BeanFactory中获取的，所以我们可以自定义 HttpHeadersFilter 达到扩展的目的 + * */ + HttpHeaders filtered = filterRequest(getHeadersFilters(), exchange); + + // 根据 Route 的元数据构造 HttpClient 然后执行请求 + Flux responseFlux = getHttpClient(route, exchange) + .headers() + .responseConnection((res, connection) -> {}); + + // 放行 + return responseFlux.then(chain.filter(exchange)); + } } ``` @@ -711,42 +711,42 @@ public class NettyRoutingFilter implements GlobalFilter, Ordered { ```java public class WebsocketRoutingFilter implements GlobalFilter, Ordered { - @Override - public int getOrder() { - // 在 NettyRoutingFilter 之前执行 - return Integer.MAX_VALUE - 1; - } - - @Override - public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { - // 有请求头 upgrade=WebSocket ，那就将 http、https 转成 ws、wss 协议 - changeSchemeIfIsWebSocketUpgrade(exchange); - - URI requestUrl = exchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR); - String scheme = requestUrl.getScheme(); - - // 已经路由过 或者 不是 ws、wss 协议 就放行 - if (isAlreadyRouted(exchange) || (!"ws".equals(scheme) && !"wss".equals(scheme))) { - return chain.filter(exchange); - } - // 标记路由了 - setAlreadyRouted(exchange); - - HttpHeaders headers = exchange.getRequest().getHeaders(); - /** - * 遍历执行所有的 HttpHeadersFilter 得到 HttpHeaders。 - * 也就是说可以对最终要执行的 请求头 进行加工 - * - * 注：HttpHeadersFilter 是从BeanFactory中获取的，所以我们可以自定义 HttpHeadersFilter 达到扩展的目的 - * */ - HttpHeaders filtered = filterRequest(getHeadersFilters(), exchange); - - List protocols = getProtocols(headers); - - // 使用 webSocketService 执行请求。且不在执行后续的filter - return this.webSocketService.handleRequest(exchange, - new ProxyWebSocketHandler(requestUrl, this.webSocketClient, filtered, protocols)); - } + @Override + public int getOrder() { + // 在 NettyRoutingFilter 之前执行 + return Integer.MAX_VALUE - 1; + } + + @Override + public Mono filter(ServerWebExchange exchange, GatewayFilterChain chain) { + // 有请求头 upgrade=WebSocket ，那就将 http、https 转成 ws、wss 协议 + changeSchemeIfIsWebSocketUpgrade(exchange); + + URI requestUrl = exchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR); + String scheme = requestUrl.getScheme(); + + // 已经路由过 或者 不是 ws、wss 协议 就放行 + if (isAlreadyRouted(exchange) || (!"ws".equals(scheme) && !"wss".equals(scheme))) { + return chain.filter(exchange); + } + // 标记路由了 + setAlreadyRouted(exchange); + + HttpHeaders headers = exchange.getRequest().getHeaders(); + /** + * 遍历执行所有的 HttpHeadersFilter 得到 HttpHeaders。 + * 也就是说可以对最终要执行的 请求头 进行加工 + * + * 注：HttpHeadersFilter 是从BeanFactory中获取的，所以我们可以自定义 HttpHeadersFilter 达到扩展的目的 + * */ + HttpHeaders filtered = filterRequest(getHeadersFilters(), exchange); + + List protocols = getProtocols(headers); + + // 使用 webSocketService 执行请求。且不在执行后续的filter + return this.webSocketService.handleRequest(exchange, + new ProxyWebSocketHandler(requestUrl, this.webSocketClient, filtered, protocols)); + } } ``` @@ -760,72 +760,72 @@ RoutePredicateHandlerMapping 是由 [GatewayAutoConfiguration](#GatewayAutoConfi ```java public class RoutePredicateHandlerMapping extends AbstractHandlerMapping { - /** - * 通过依赖注入得到这些bean - */ - public RoutePredicateHandlerMapping(FilteringWebHandler webHandler, RouteLocator routeLocator, - GlobalCorsProperties globalCorsProperties, Environment environment) { - this.webHandler = webHandler; - this.routeLocator = routeLocator; - /** - * 获取属性作为 order 值，默认是1。从而决定是 DispatcherHandler 使用的第几个 HandlerMapping， - * 因为 HandlerMapping 的特点是能处理就使用，不在使用其他的 HandlerMapping，所以优先级是很重要的。 - * */ - setOrder(environment.getProperty(GatewayProperties.PREFIX + ".handler-mapping.order", Integer.class, 1)); - // 设置同源配置信息 - setCorsConfigurations(globalCorsProperties.getCorsConfigurations()); - } - - /** - * 返回值不是 Mono.empty() 就表示 RoutePredicateHandlerMapping 命中了， - * 就会执行 HandlerAdapter.handle(serverWebExchange,webHandler) - */ - @Override - protected Mono getHandlerInternal(ServerWebExchange exchange) { - // 设置一个属性 - exchange.getAttributes().put(GATEWAY_HANDLER_MAPPER_ATTR, getSimpleName()); - /** - * 使用 routeLocator 得到 List 遍历 - * */ - return lookupRoute(exchange) - .flatMap((Function>) r -> { - exchange.getAttributes().remove(GATEWAY_PREDICATE_ROUTE_ATTR); - /** - * 将 Route 设置到 exchange 中 - * - * 后续流程会用到 - * {@link FilteringWebHandler#handle(ServerWebExchange)} - * */ - exchange.getAttributes().put(GATEWAY_ROUTE_ATTR, r); - /** - * 会由 SimpleHandlerAdapter 处理 - * */ - return Mono.just(webHandler); - }).switchIfEmpty(Mono.empty().then(Mono.fromRunnable(() -> { - exchange.getAttributes().remove(GATEWAY_PREDICATE_ROUTE_ATTR); - }))); - } - - protected Mono lookupRoute(ServerWebExchange exchange) { - /** - * 得到 Route，根据 Route 的 Predicate 决定是否匹配 - * */ - return this.routeLocator.getRoutes() - /** - * concatMap 的特点是 返回的内容不是 Mono.empty() 、Flux.empty() 才收集到 Flux 中 - * */ - .concatMap(route -> Mono.just(route).filterWhen(r -> { - // exchange 中存一下 routeId - exchange.getAttributes().put(GATEWAY_PREDICATE_ROUTE_ATTR, r.getId()); - /** - * 执行谓词 - * {@link AsyncPredicate.AndAsyncPredicate#apply(Object)} - * */ - return r.getPredicate().apply(exchange); - }).onErrorResume(e -> Mono.empty())) - // 拿到第一个。所以 Route 的顺序会决定最终的方法的执行 - .next(); - } + /** + * 通过依赖注入得到这些bean + */ + public RoutePredicateHandlerMapping(FilteringWebHandler webHandler, RouteLocator routeLocator, + GlobalCorsProperties globalCorsProperties, Environment environment) { + this.webHandler = webHandler; + this.routeLocator = routeLocator; + /** + * 获取属性作为 order 值，默认是1。从而决定是 DispatcherHandler 使用的第几个 HandlerMapping， + * 因为 HandlerMapping 的特点是能处理就使用，不在使用其他的 HandlerMapping，所以优先级是很重要的。 + * */ + setOrder(environment.getProperty(GatewayProperties.PREFIX + ".handler-mapping.order", Integer.class, 1)); + // 设置同源配置信息 + setCorsConfigurations(globalCorsProperties.getCorsConfigurations()); + } + + /** + * 返回值不是 Mono.empty() 就表示 RoutePredicateHandlerMapping 命中了， + * 就会执行 HandlerAdapter.handle(serverWebExchange,webHandler) + */ + @Override + protected Mono getHandlerInternal(ServerWebExchange exchange) { + // 设置一个属性 + exchange.getAttributes().put(GATEWAY_HANDLER_MAPPER_ATTR, getSimpleName()); + /** + * 使用 routeLocator 得到 List 遍历 + * */ + return lookupRoute(exchange) + .flatMap((Function>) r -> { + exchange.getAttributes().remove(GATEWAY_PREDICATE_ROUTE_ATTR); + /** + * 将 Route 设置到 exchange 中 + * + * 后续流程会用到 + * {@link FilteringWebHandler#handle(ServerWebExchange)} + * */ + exchange.getAttributes().put(GATEWAY_ROUTE_ATTR, r); + /** + * 会由 SimpleHandlerAdapter 处理 + * */ + return Mono.just(webHandler); + }).switchIfEmpty(Mono.empty().then(Mono.fromRunnable(() -> { + exchange.getAttributes().remove(GATEWAY_PREDICATE_ROUTE_ATTR); + }))); + } + + protected Mono lookupRoute(ServerWebExchange exchange) { + /** + * 得到 Route，根据 Route 的 Predicate 决定是否匹配 + * */ + return this.routeLocator.getRoutes() + /** + * concatMap 的特点是 返回的内容不是 Mono.empty() 、Flux.empty() 才收集到 Flux 中 + * */ + .concatMap(route -> Mono.just(route).filterWhen(r -> { + // exchange 中存一下 routeId + exchange.getAttributes().put(GATEWAY_PREDICATE_ROUTE_ATTR, r.getId()); + /** + * 执行谓词 + * {@link AsyncPredicate.AndAsyncPredicate#apply(Object)} + * */ + return r.getPredicate().apply(exchange); + }).onErrorResume(e -> Mono.empty())) + // 拿到第一个。所以 Route 的顺序会决定最终的方法的执行 + .next(); + } } ``` @@ -853,7 +853,7 @@ public class CachingRouteLocator private ApplicationEventPublisher applicationEventPublisher; public CachingRouteLocator(RouteLocator delegate) { - // 是这个 CompositeRouteLocator + // 是这个 CompositeRouteLocator this.delegate = delegate; // 使用 ConcurrentHashMap 缓存 Route，缓存中没有就执行 fetch 方法得到 routes = CacheFlux.lookup(cache, CACHE_KEY, Route.class).onCacheMissResume(this::fetch); @@ -900,191 +900,191 @@ RouteDefinitionRouteLocator 是由 [GatewayAutoConfiguration](#GatewayAutoConfig ```java public class RouteDefinitionRouteLocator implements RouteLocator { - /** - * 通过依赖注入得到 - */ - public RouteDefinitionRouteLocator(RouteDefinitionLocator routeDefinitionLocator, - List predicates, List gatewayFilterFactories, - GatewayProperties gatewayProperties, ConfigurationService configurationService) { - this.routeDefinitionLocator = routeDefinitionLocator; - this.configurationService = configurationService; - /** - * 将 List 转成 Map，key 是执行 {@link RoutePredicateFactory#name()} 得到的。 - * 默认的逻辑是 类名去除 RoutePredicateFactory - * 比如 AddHeadRoutePredicateFactory 的key是 AddHead - * */ - initFactories(predicates); - /** - * 逻辑同上 {@link GatewayFilterFactory#name()} - * 默认的逻辑是 类名去除 GatewayFilterFactory - * 比如 AddRequestHeaderGatewayFilterFactory 的key是 AddRequestHeader - * */ - gatewayFilterFactories.forEach(factory -> this.gatewayFilterFactories.put(factory.name(), factory)); - this.gatewayProperties = gatewayProperties; - } - - @Override - public Flux getRoutes() { - /** - * 通过 RouteDefinitionLocator 得到 RouteDefinition ，然后根据 RouteDefinition 转成 Route - * */ - Flux routes = this.routeDefinitionLocator.getRouteDefinitions().map(this::convertToRoute); - return routes; - } - - private Route convertToRoute(RouteDefinition routeDefinition) { - /** - * 会根据定义 predicates 的顺序，遍历处理。根据 predicate.getName() 找到 RoutePredicateFactory， - * 再使用 factory 生成 AsyncPredicate - * */ - AsyncPredicate predicate = combinePredicates(routeDefinition); - /** - * 先处理通过属性定义的 默认Filter（spring.cloud.gateway.defaultFilters），再根据定义 filters 的顺序，遍历处理。根据 filter.getName() 找到 GatewayFilterFactory， - * 再使用 factory 生成 GatewayFilter - * - * 最后会根据 order 进行排序。 - * */ - List gatewayFilters = getFilters(routeDefinition); - - // 构造出 Route - return Route.async(routeDefinition).asyncPredicate(predicate).replaceFilters(gatewayFilters).build(); - } - - @SuppressWarnings("unchecked") - List loadGatewayFilters(String id, List filterDefinitions) { - ArrayList ordered = new ArrayList<>(filterDefinitions.size()); - for (int i = 0; i < filterDefinitions.size(); i++) { - FilterDefinition definition = filterDefinitions.get(i); - // 根据 definition.getName() 拿到 GatewayFilterFactory - GatewayFilterFactory factory = this.gatewayFilterFactories.get(definition.getName()); - if (factory == null) { - throw new IllegalArgumentException( - "Unable to find GatewayFilterFactory with name " + definition.getName()); - } - - /** - * 使用 configurationService 生成 configuration - * - * 和这个是一样的的，看这里就知道了 - * {@link RouteDefinitionRouteLocator#lookup(RouteDefinition, PredicateDefinition)} - * */ - // @formatter:off - Object configuration = this.configurationService.with(factory) - .name(definition.getName()) - .properties(definition.getArgs()) - .eventFunction((bound, properties) -> new FilterArgsEvent( - // TODO: why explicit cast needed or java compile fails - RouteDefinitionRouteLocator.this, id, (Map) properties)) - .bind(); - // @formatter:on - - if (configuration instanceof HasRouteId) { - HasRouteId hasRouteId = (HasRouteId) configuration; - // 设置 routeId - hasRouteId.setRouteId(id); - } - - // factory 根据 configuration 生成 GatewayFilter - GatewayFilter gatewayFilter = factory.apply(configuration); - if (gatewayFilter instanceof Ordered) { - ordered.add(gatewayFilter); - } - else { - // 默认的 order 值 就是 定义 filter 的顺序 - ordered.add(new OrderedGatewayFilter(gatewayFilter, i + 1)); - } - } - - return ordered; - } - - private List getFilters(RouteDefinition routeDefinition) { - List filters = new ArrayList<>(); - - if (!this.gatewayProperties.getDefaultFilters().isEmpty()) { - /** - * 先添加通过属性定义的默认Filter - * spring.cloud.gateway.defaultFilters=[f1,f2] - * */ - filters.addAll(loadGatewayFilters(routeDefinition.getId(), - new ArrayList<>(this.gatewayProperties.getDefaultFilters()))); - } - - final List definitionFilters = routeDefinition.getFilters(); - if (!CollectionUtils.isEmpty(definitionFilters)) { - // 再添加 RouteDefinition 定义的 filter - filters.addAll(loadGatewayFilters(routeDefinition.getId(), definitionFilters)); - } - - // 排序 - AnnotationAwareOrderComparator.sort(filters); - return filters; - } - - private AsyncPredicate combinePredicates(RouteDefinition routeDefinition) { - List predicates = routeDefinition.getPredicates(); - // routeDefinition 没有定义 predicate ，就设置一个返回 ture 的 AsyncPredicate - if (predicates == null || predicates.isEmpty()) { - // this is a very rare case, but possible, just match all - return AsyncPredicate.from(exchange -> true); - } - - /** - * 获取 AsyncPredicate。 - * - * 会根据 predicate.getName() 拿到 RoutePredicateFactory，执行 RoutePredicateFactory.apply(config) 生成 AsyncPredicate - * */ - AsyncPredicate predicate = lookup(routeDefinition, predicates.get(0)); - // 遍历剩下的 predicate - for (PredicateDefinition andPredicate : predicates.subList(1, predicates.size())) { - AsyncPredicate found = lookup(routeDefinition, andPredicate); - /** - * and 的连接多个 predicate。返回的是这个类型 AndAsyncPredicate - * - * 其实就是不断的套娃。 - * */ - predicate = predicate.and(found); - } - - return predicate; - } - - @SuppressWarnings("unchecked") - private AsyncPredicate lookup(RouteDefinition route, PredicateDefinition predicate) { - /** - * predicates 是根据 BeanFactory 中 RoutePredicateFactory 类型的 bean 生成的。 - * 所以可以理解成是从 BeanFactory 中得到 RoutePredicateFactory。 - * */ - RoutePredicateFactory factory = this.predicates.get(predicate.getName()); - if (factory == null) { - throw new IllegalArgumentException("Unable to find RoutePredicateFactory with name " + predicate.getName()); - } - if (logger.isDebugEnabled()) { - logger.debug("RouteDefinition " + route.getId() + " applying " + predicate.getArgs() + " to " - + predicate.getName()); - } - - /** - * factory 实现 ShortcutConfigurable 接口，规定如何生成的 属性绑定的Map - * factory 实现 Configurable 接口，规定使用 config 是啥 - * - * configurationService 会依赖 factory 生成 属性绑定的Map 得到 Config 的类型 - * 然后使用 属性绑定的Map + ConversionsService + Validator 实例化 Config ，并且会对 Config 进行属性绑定和属性校验（JSR303） - * */ - // @formatter:off - Object config = this.configurationService.with(factory) - .name(predicate.getName()) - // 设置属性。会根据这个生成用于属性绑定的Map - .properties(predicate.getArgs()) - // 定义事件。对 config 完成属性绑定完后，会发布这个事件 - .eventFunction((bound, properties) -> new PredicateArgsEvent( - RouteDefinitionRouteLocator.this, route.getId(), properties)) - .bind(); - // @formatter:on - - // 根据 config 使用 factory 生成 AsyncPredicate - return factory.applyAsync(config); - } + /** + * 通过依赖注入得到 + */ + public RouteDefinitionRouteLocator(RouteDefinitionLocator routeDefinitionLocator, + List predicates, List gatewayFilterFactories, + GatewayProperties gatewayProperties, ConfigurationService configurationService) { + this.routeDefinitionLocator = routeDefinitionLocator; + this.configurationService = configurationService; + /** + * 将 List 转成 Map，key 是执行 {@link RoutePredicateFactory#name()} 得到的。 + * 默认的逻辑是 类名去除 RoutePredicateFactory + * 比如 AddHeadRoutePredicateFactory 的key是 AddHead + * */ + initFactories(predicates); + /** + * 逻辑同上 {@link GatewayFilterFactory#name()} + * 默认的逻辑是 类名去除 GatewayFilterFactory + * 比如 AddRequestHeaderGatewayFilterFactory 的key是 AddRequestHeader + * */ + gatewayFilterFactories.forEach(factory -> this.gatewayFilterFactories.put(factory.name(), factory)); + this.gatewayProperties = gatewayProperties; + } + + @Override + public Flux getRoutes() { + /** + * 通过 RouteDefinitionLocator 得到 RouteDefinition ，然后根据 RouteDefinition 转成 Route + * */ + Flux routes = this.routeDefinitionLocator.getRouteDefinitions().map(this::convertToRoute); + return routes; + } + + private Route convertToRoute(RouteDefinition routeDefinition) { + /** + * 会根据定义 predicates 的顺序，遍历处理。根据 predicate.getName() 找到 RoutePredicateFactory， + * 再使用 factory 生成 AsyncPredicate + * */ + AsyncPredicate predicate = combinePredicates(routeDefinition); + /** + * 先处理通过属性定义的 默认Filter（spring.cloud.gateway.defaultFilters），再根据定义 filters 的顺序，遍历处理。根据 filter.getName() 找到 GatewayFilterFactory， + * 再使用 factory 生成 GatewayFilter + * + * 最后会根据 order 进行排序。 + * */ + List gatewayFilters = getFilters(routeDefinition); + + // 构造出 Route + return Route.async(routeDefinition).asyncPredicate(predicate).replaceFilters(gatewayFilters).build(); + } + + @SuppressWarnings("unchecked") + List loadGatewayFilters(String id, List filterDefinitions) { + ArrayList ordered = new ArrayList<>(filterDefinitions.size()); + for (int i = 0; i < filterDefinitions.size(); i++) { + FilterDefinition definition = filterDefinitions.get(i); + // 根据 definition.getName() 拿到 GatewayFilterFactory + GatewayFilterFactory factory = this.gatewayFilterFactories.get(definition.getName()); + if (factory == null) { + throw new IllegalArgumentException( + "Unable to find GatewayFilterFactory with name " + definition.getName()); + } + + /** + * 使用 configurationService 生成 configuration + * + * 和这个是一样的的，看这里就知道了 + * {@link RouteDefinitionRouteLocator#lookup(RouteDefinition, PredicateDefinition)} + * */ + // @formatter:off + Object configuration = this.configurationService.with(factory) + .name(definition.getName()) + .properties(definition.getArgs()) + .eventFunction((bound, properties) -> new FilterArgsEvent( + // TODO: why explicit cast needed or java compile fails + RouteDefinitionRouteLocator.this, id, (Map) properties)) + .bind(); + // @formatter:on + + if (configuration instanceof HasRouteId) { + HasRouteId hasRouteId = (HasRouteId) configuration; + // 设置 routeId + hasRouteId.setRouteId(id); + } + + // factory 根据 configuration 生成 GatewayFilter + GatewayFilter gatewayFilter = factory.apply(configuration); + if (gatewayFilter instanceof Ordered) { + ordered.add(gatewayFilter); + } + else { + // 默认的 order 值 就是 定义 filter 的顺序 + ordered.add(new OrderedGatewayFilter(gatewayFilter, i + 1)); + } + } + + return ordered; + } + + private List getFilters(RouteDefinition routeDefinition) { + List filters = new ArrayList<>(); + + if (!this.gatewayProperties.getDefaultFilters().isEmpty()) { + /** + * 先添加通过属性定义的默认Filter + * spring.cloud.gateway.defaultFilters=[f1,f2] + * */ + filters.addAll(loadGatewayFilters(routeDefinition.getId(), + new ArrayList<>(this.gatewayProperties.getDefaultFilters()))); + } + + final List definitionFilters = routeDefinition.getFilters(); + if (!CollectionUtils.isEmpty(definitionFilters)) { + // 再添加 RouteDefinition 定义的 filter + filters.addAll(loadGatewayFilters(routeDefinition.getId(), definitionFilters)); + } + + // 排序 + AnnotationAwareOrderComparator.sort(filters); + return filters; + } + + private AsyncPredicate combinePredicates(RouteDefinition routeDefinition) { + List predicates = routeDefinition.getPredicates(); + // routeDefinition 没有定义 predicate ，就设置一个返回 ture 的 AsyncPredicate + if (predicates == null || predicates.isEmpty()) { + // this is a very rare case, but possible, just match all + return AsyncPredicate.from(exchange -> true); + } + + /** + * 获取 AsyncPredicate。 + * + * 会根据 predicate.getName() 拿到 RoutePredicateFactory，执行 RoutePredicateFactory.apply(config) 生成 AsyncPredicate + * */ + AsyncPredicate predicate = lookup(routeDefinition, predicates.get(0)); + // 遍历剩下的 predicate + for (PredicateDefinition andPredicate : predicates.subList(1, predicates.size())) { + AsyncPredicate found = lookup(routeDefinition, andPredicate); + /** + * and 的连接多个 predicate。返回的是这个类型 AndAsyncPredicate + * + * 其实就是不断的套娃。 + * */ + predicate = predicate.and(found); + } + + return predicate; + } + + @SuppressWarnings("unchecked") + private AsyncPredicate lookup(RouteDefinition route, PredicateDefinition predicate) { + /** + * predicates 是根据 BeanFactory 中 RoutePredicateFactory 类型的 bean 生成的。 + * 所以可以理解成是从 BeanFactory 中得到 RoutePredicateFactory。 + * */ + RoutePredicateFactory factory = this.predicates.get(predicate.getName()); + if (factory == null) { + throw new IllegalArgumentException("Unable to find RoutePredicateFactory with name " + predicate.getName()); + } + if (logger.isDebugEnabled()) { + logger.debug("RouteDefinition " + route.getId() + " applying " + predicate.getArgs() + " to " + + predicate.getName()); + } + + /** + * factory 实现 ShortcutConfigurable 接口，规定如何生成的 属性绑定的Map + * factory 实现 Configurable 接口，规定使用 config 是啥 + * + * configurationService 会依赖 factory 生成 属性绑定的Map 得到 Config 的类型 + * 然后使用 属性绑定的Map + ConversionsService + Validator 实例化 Config ，并且会对 Config 进行属性绑定和属性校验（JSR303） + * */ + // @formatter:off + Object config = this.configurationService.with(factory) + .name(predicate.getName()) + // 设置属性。会根据这个生成用于属性绑定的Map + .properties(predicate.getArgs()) + // 定义事件。对 config 完成属性绑定完后，会发布这个事件 + .eventFunction((bound, properties) -> new PredicateArgsEvent( + RouteDefinitionRouteLocator.this, route.getId(), properties)) + .bind(); + // @formatter:on + + // 根据 config 使用 factory 生成 AsyncPredicate + return factory.applyAsync(config); + } } ``` @@ -1101,21 +1101,21 @@ PropertiesRouteDefinitionLocator 是由 [GatewayAutoConfiguration](#GatewayAutoC ```java public class PropertiesRouteDefinitionLocator implements RouteDefinitionLocator { - public PropertiesRouteDefinitionLocator(GatewayProperties properties) { - /** - * 依赖注入得到的 - * - * GatewayProperties 标注了 @ConfigurationProperties("spring.cloud.gateway") - * 所以会通过属性绑定设置值 - * */ - this.properties = properties; - } - - @Override - public Flux getRouteDefinitions() { - // 直接返回 properties.getRoutes() - return Flux.fromIterable(this.properties.getRoutes()); - } + public PropertiesRouteDefinitionLocator(GatewayProperties properties) { + /** + * 依赖注入得到的 + * + * GatewayProperties 标注了 @ConfigurationProperties("spring.cloud.gateway") + * 所以会通过属性绑定设置值 + * */ + this.properties = properties; + } + + @Override + public Flux getRouteDefinitions() { + // 直接返回 properties.getRoutes() + return Flux.fromIterable(this.properties.getRoutes()); + } } ``` @@ -1133,45 +1133,45 @@ RouteDefinitionRepository 的职责是通过缓存的方式记录 RouteDefinitio ```java public class InMemoryRouteDefinitionRepository implements RouteDefinitionRepository { - // 线程安全的 - private final Map routes = synchronizedMap(new LinkedHashMap()); - - @Override - public Mono save(Mono route) { - /** - * Gateway Endpoint 会依赖 RouteDefinitionRepository 类型的bean 记录通过 Endpoint 动态添加的 RouteDefinition - * - * 源码在这里 - * {@link AbstractGatewayControllerEndpoint#save(String, RouteDefinition)} - * */ - return route.flatMap(r -> { - if (ObjectUtils.isEmpty(r.getId())) { - return Mono.error(new IllegalArgumentException("id may not be empty")); - } - // 存到缓存中 - routes.put(r.getId(), r); - return Mono.empty(); - }); - } - - @Override - public Mono delete(Mono routeId) { - return routeId.flatMap(id -> { - if (routes.containsKey(id)) { - // 从缓存中移除 - routes.remove(id); + // 线程安全的 + private final Map routes = synchronizedMap(new LinkedHashMap()); + + @Override + public Mono save(Mono route) { + /** + * Gateway Endpoint 会依赖 RouteDefinitionRepository 类型的bean 记录通过 Endpoint 动态添加的 RouteDefinition + * + * 源码在这里 + * {@link AbstractGatewayControllerEndpoint#save(String, RouteDefinition)} + * */ + return route.flatMap(r -> { + if (ObjectUtils.isEmpty(r.getId())) { + return Mono.error(new IllegalArgumentException("id may not be empty")); + } + // 存到缓存中 + routes.put(r.getId(), r); return Mono.empty(); - } - return Mono.defer(() -> Mono.error(new NotFoundException("RouteDefinition not found: " + routeId))); - }); - } - - @Override - public Flux getRouteDefinitions() { - // 返回缓存中的值 - Map routesSafeCopy = new LinkedHashMap<>(routes); - return Flux.fromIterable(routesSafeCopy.values()); - } + }); + } + + @Override + public Mono delete(Mono routeId) { + return routeId.flatMap(id -> { + if (routes.containsKey(id)) { + // 从缓存中移除 + routes.remove(id); + return Mono.empty(); + } + return Mono.defer(() -> Mono.error(new NotFoundException("RouteDefinition not found: " + routeId))); + }); + } + + @Override + public Flux getRouteDefinitions() { + // 返回缓存中的值 + Map routesSafeCopy = new LinkedHashMap<>(routes); + return Flux.fromIterable(routesSafeCopy.values()); + } } ``` @@ -1195,45 +1195,45 @@ RouteRefreshListener 是由 [GatewayAutoConfiguration](#GatewayAutoConfiguration ```java public class RouteRefreshListener implements ApplicationListener { - @Override - public void onApplicationEvent(ApplicationEvent event) { - // 这是 IOC 容器 refresh 的最后阶段会发布的事件 - if (event instanceof ContextRefreshedEvent) { - ContextRefreshedEvent refreshedEvent = (ContextRefreshedEvent) event; - // 不是 - if (!WebServerApplicationContext.hasServerNamespace(refreshedEvent.getApplicationContext(), "management")) { - /** - * 重设 - * - * 其实就是发布一个 RefreshRoutesEvent 事件， - * 该事件会由 CachingRouteLocator 接收，会对 List 进行缓存 - * {@link CachingRouteLocator#onApplicationEvent(RefreshRoutesEvent)} - * */ + @Override + public void onApplicationEvent(ApplicationEvent event) { + // 这是 IOC 容器 refresh 的最后阶段会发布的事件 + if (event instanceof ContextRefreshedEvent) { + ContextRefreshedEvent refreshedEvent = (ContextRefreshedEvent) event; + // 不是 + if (!WebServerApplicationContext.hasServerNamespace(refreshedEvent.getApplicationContext(), "management")) { + /** + * 重设 + * + * 其实就是发布一个 RefreshRoutesEvent 事件， + * 该事件会由 CachingRouteLocator 接收，会对 List 进行缓存 + * {@link CachingRouteLocator#onApplicationEvent(RefreshRoutesEvent)} + * */ + reset(); + } + } + else if (event instanceof RefreshScopeRefreshedEvent || event instanceof InstanceRegisteredEvent) { reset(); - } - } - else if (event instanceof RefreshScopeRefreshedEvent || event instanceof InstanceRegisteredEvent) { - reset(); - } - else if (event instanceof ParentHeartbeatEvent) { - ParentHeartbeatEvent e = (ParentHeartbeatEvent) event; - resetIfNeeded(e.getValue()); - } - else if (event instanceof HeartbeatEvent) { - HeartbeatEvent e = (HeartbeatEvent) event; - resetIfNeeded(e.getValue()); - } - } - - private void resetIfNeeded(Object value) { - if (this.monitor.update(value)) { - reset(); - } - } - - private void reset() { - this.publisher.publishEvent(new RefreshRoutesEvent(this)); - } + } + else if (event instanceof ParentHeartbeatEvent) { + ParentHeartbeatEvent e = (ParentHeartbeatEvent) event; + resetIfNeeded(e.getValue()); + } + else if (event instanceof HeartbeatEvent) { + HeartbeatEvent e = (HeartbeatEvent) event; + resetIfNeeded(e.getValue()); + } + } + + private void resetIfNeeded(Object value) { + if (this.monitor.update(value)) { + reset(); + } + } + + private void reset() { + this.publisher.publishEvent(new RefreshRoutesEvent(this)); + } } ``` @@ -1248,65 +1248,65 @@ FilteringWebHandler 是由 [GatewayAutoConfiguration](#GatewayAutoConfiguration) ```java public class FilteringWebHandler implements WebHandler { - public FilteringWebHandler(List globalFilters) { - // 这是依赖注入得到的 - this.globalFilters = loadFilters(globalFilters); - } - - private static List loadFilters(List filters) { - return filters.stream().map(filter -> { - // 装饰成 GatewayFilter 类型 - GatewayFilterAdapter gatewayFilter = new GatewayFilterAdapter(filter); - if (filter instanceof Ordered) { - int order = ((Ordered) filter).getOrder(); - return new OrderedGatewayFilter(gatewayFilter, order); - } - return gatewayFilter; - }).collect(Collectors.toList()); - } - @Override - public Mono handle(ServerWebExchange exchange) { - /** - * 拿到 Route 实例。这个是在前一个步骤设置的 - * {@link RoutePredicateHandlerMapping#getHandlerInternal(ServerWebExchange)} - * */ - Route route = exchange.getRequiredAttribute(GATEWAY_ROUTE_ATTR); - // 拿到 Route 的 GatewayFilter - List gatewayFilters = route.getFilters(); - - // 先添加 globalFilter - List combined = new ArrayList<>(this.globalFilters); - // 再添加 route 定义的 Filter - combined.addAll(gatewayFilters); - - // 排序 - AnnotationAwareOrderComparator.sort(combined); - - /** - * 装饰成 DefaultGatewayFilterChain 执行。 - * - * 其实就是遍历执行所有的 GatewayFilter - * */ - return new DefaultGatewayFilterChain(combined).filter(exchange); - } - - private static class DefaultGatewayFilterChain implements GatewayFilterChain { - @Override - public Mono filter(ServerWebExchange exchange) { - return Mono.defer(() -> { - if (this.index < filters.size()) { - GatewayFilter filter = filters.get(this.index); - // 套娃行为 - DefaultGatewayFilterChain chain = new DefaultGatewayFilterChain(this, this.index + 1); - // 执行 - return filter.filter(exchange, chain); - } - else { - return Mono.empty(); // complete + public FilteringWebHandler(List globalFilters) { + // 这是依赖注入得到的 + this.globalFilters = loadFilters(globalFilters); + } + + private static List loadFilters(List filters) { + return filters.stream().map(filter -> { + // 装饰成 GatewayFilter 类型 + GatewayFilterAdapter gatewayFilter = new GatewayFilterAdapter(filter); + if (filter instanceof Ordered) { + int order = ((Ordered) filter).getOrder(); + return new OrderedGatewayFilter(gatewayFilter, order); } - }); - } + return gatewayFilter; + }).collect(Collectors.toList()); + } + @Override + public Mono handle(ServerWebExchange exchange) { + /** + * 拿到 Route 实例。这个是在前一个步骤设置的 + * {@link RoutePredicateHandlerMapping#getHandlerInternal(ServerWebExchange)} + * */ + Route route = exchange.getRequiredAttribute(GATEWAY_ROUTE_ATTR); + // 拿到 Route 的 GatewayFilter + List gatewayFilters = route.getFilters(); + + // 先添加 globalFilter + List combined = new ArrayList<>(this.globalFilters); + // 再添加 route 定义的 Filter + combined.addAll(gatewayFilters); + + // 排序 + AnnotationAwareOrderComparator.sort(combined); + + /** + * 装饰成 DefaultGatewayFilterChain 执行。 + * + * 其实就是遍历执行所有的 GatewayFilter + * */ + return new DefaultGatewayFilterChain(combined).filter(exchange); + } - } + private static class DefaultGatewayFilterChain implements GatewayFilterChain { + @Override + public Mono filter(ServerWebExchange exchange) { + return Mono.defer(() -> { + if (this.index < filters.size()) { + GatewayFilter filter = filters.get(this.index); + // 套娃行为 + DefaultGatewayFilterChain chain = new DefaultGatewayFilterChain(this, this.index + 1); + // 执行 + return filter.filter(exchange, chain); + } + else { + return Mono.empty(); // complete + } + }); + } + + } } ```