Spring Cloud Gateway 无法从 eureka 服务器解析服务 ID

Question

跟着@​​987654321@搭建了eureka server、spring cloud gateway和一个示例rest service。

但是，网关无法使用来自 eureka 服务器的服务名称检索 url。 网关和服务的注册似乎没问题。 当提供实际端点而不是服务 ID 时，它可以正常工作。 我无法理解为什么网关没有从尤里卡解析服务 ID。我是否缺少任何配置？

错误信息：

2018-09-05 23:20:17.751  INFO 47037 --- [ctor-http-nio-2] c.netflix.loadbalancer.BaseLoadBalancer  : Client: localhost instantiated a LoadBalancer: DynamicServerListLoadBalancer:{NFLoadBalancer:name=localhost,current list of Servers=[],Load balancer stats=Zone stats: {},Server stats: []}ServerList:null
2018-09-05 23:20:17.756  INFO 47037 --- [ctor-http-nio-2] c.n.l.DynamicServerListLoadBalancer      : Using serverListUpdater PollingServerListUpdater
2018-09-05 23:20:17.760  INFO 47037 --- [ctor-http-nio-2] c.n.l.DynamicServerListLoadBalancer      : DynamicServerListLoadBalancer for client localhost initialized: DynamicServerListLoadBalancer:{NFLoadBalancer:name=localhost,current list of Servers=[],Load balancer stats=Zone stats: {},Server stats: []}ServerList:org.springframework.cloud.netflix.ribbon.eureka.DomainExtractingServerList@107dc063
2018-09-05 23:20:17.822 ERROR 47037 --- [ctor-http-nio-2] .a.w.r.e.DefaultErrorWebExceptionHandler : Failed to handle request [GET http://localhost:8080/rest-service/hello]

org.springframework.cloud.gateway.support.NotFoundException: Unable to find instance for localhost
    at org.springframework.cloud.gateway.filter.LoadBalancerClientFilter.filter(LoadBalancerClientFilter.java:72) ~[spring-cloud-gateway-core-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.cloud.gateway.handler.FilteringWebHandler$GatewayFilterAdapter.filter(FilteringWebHandler.java:133) ~[spring-cloud-gateway-core-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.cloud.gateway.filter.OrderedGatewayFilter.filter(OrderedGatewayFilter.java:44) ~[spring-cloud-gateway-core-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain.lambda$filter$0(FilteringWebHandler.java:115) ~[spring-cloud-gateway-core-2.0.1.RELEASE.jar:2.0.1.RELEASE]
    at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:45) ~[reactor-core-3.1.8.RELEASE.jar:3.1.8.RELEASE]

服务注册：

附上代码链接：

• Eureka Server
• Spring Cloud Gateway
• Rest service

Answer 1

问题在于 Spring Cloud Gateway 从 eureka 访问服务名称的方式，它区分大小写。解决方法是在 application.yml 中添加以下属性

spring.cloud.gateway.discovery.locator.lower-case-service-id= true
spring.cloud.gateway.discovery.locator.enabled= true

I have created a sample project to show all of them working together.

Answer 2

除了接受的答案外，请确保添加 DiscoveryClient 依赖项：

10.2 DiscoveryClient 路由定义定位器

网关可以配置为基于在与 DiscoveryClient 兼容的服务注册表中注册的服务创建路由。

要启用此功能，请设置 spring.cloud.gateway.discovery.locator.enabled=true 并确保 DiscoveryClient 实现位于类路径上并已启用（例如 Netflix Eureka、Consul 或 Zookeeper）。

见10.2 DiscoveryClient Route Definition Locator

Answer 3

如果您使用 WebClient 从 spring cloud gateway-service 对其他微服务进行 API 调用，请确保您在配置类中注释 WebClient.Builder。

@Configuration
@EnableConfigurationProperties
@ConfigurationProperties
@Component
public class ContentConfig {

    @Bean
    @LoadBalanced
    public WebClient.Builder loadBalancedWebClientBuilder() {
        return WebClient.builder();
    }
}

然后在您的提供者或服务类@AutoWired WebClient bean 中，

@Autowired
public WebClient.Builder webClientBuilder;