使用 Eureka 向 WebFlux 注册微服务时遇到问题

Question

在 Java + Spring 应用程序上使用 Netflix Eureka 作为服务发现并获得 HTTP: 503。当地址固定在代码上时，应用程序可以正常工作。

我试过：

SpringDeveloper - Spring 开发者视频

Secure Reactive Microservices - Spring 来自 Okta Developers 的云网关

Spring Cloud Hands On - 来自 Packt

的实践 Spring

由于我使用的是 WebFlux 我需要在 WebClient

上使用 @LoadBalanced

服务发现`pom.xml`

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.2.RELEASE</version>
</parent>

<properties>
        <java.version>11</java.version>
        <spring-cloud.version>Hoxton.RELEASE</spring-cloud.version>
</properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jaxb</groupId>
            <artifactId>jaxb-runtime</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

服务发现属性：

server.port=8761
eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false

服务发现main:

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

@SpringBootApplication
@EnableEurekaServer
public class ServiceDiscoveryApplication {

    public static void main(String[] args) {
        SpringApplication.run(ServiceDiscoveryApplication.class, args);
    }
}

网关`pom.xml`（相同，来自服务发现`pom.xml`

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-webflux</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.projectreactor</groupId>
            <artifactId>reactor-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-commons</artifactId>
        </dependency>
    </dependencies>

网关application.properties:

eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false
spring.application.name=gateway
server.port=8080
spring.cloud.loadbalancer.ribbon.enabled=false

网关的配置 Class：

@Component
public class LoadBalancers {

    @Bean
    public RouteLocator routeLocator(RouteLocatorBuilder routeLocatorBuilder){
        return routeLocatorBuilder.routes()
                .route("customer-service", route -> route.path("/customers")
                        .uri("lb://customer-service"))
                .route("property-service", route -> route.path("/property")
                        .uri("lb://property-service"))
                .build();
    }

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

}

服务class:

@Service
public class CustomerWebService {

    private static final String CUSTOMERS_WITH_ID = "/customers/{id}";
    private static final String CUSTOMER_ROOT_ENDPOINT = "/customers";

    private String baseUrl = "lb://customer-service/customers";

    @LoadBalanced
    private final WebClient.Builder webClient;

    public CustomerWebService(WebClient.Builder webClient) {
        this.webClient = webClient;
    }

    public Mono<Customer> findById(String id){
        return webClient.build()
                .get()
                .uri(baseUrl, id)
                .retrieve()
                .bodyToMono(Customer.class);
    }
}

当我尝试从提供商服务执行 GET 时，我得到以下信息：

2019-12-25 20:23:13.737  INFO 9552 --- [main] o.s.b.web.embedded.netty.NettyWebServer  : Netty started on port(s): 8080
2019-12-25 20:23:13.738  INFO 9552 --- [main] .s.c.n.e.s.EurekaAutoServiceRegistration : Updating port to 8080
2019-12-25 20:23:14.082  INFO 9552 --- [main] b.c.i.webportal.WebportalApplication     : Started WebportalApplication in 4.582 seconds (JVM running for 5.051)
2019-12-25 20:23:35.015  WARN 9552 --- [ctor-http-nio-3] o.s.c.l.core.RoundRobinLoadBalancer      : No servers available for service: customer-service
2019-12-25 20:23:35.016  WARN 9552 --- [ctor-http-nio-3] eactorLoadBalancerExchangeFilterFunction : Load balancer does not contain an instance for the service customer-service
2019-12-25 20:23:35.077 ERROR 9552 --- [ctor-http-nio-3] a.w.r.e.AbstractErrorWebExceptionHandler : [e3de4777]  500 Server Error for HTTP GET "/v1/customers"

org.springframework.web.reactive.function.client.WebClientResponseException$ServiceUnavailable: 503 Service Unavailable from UNKNOWN 
    at org.springframework.web.reactive.function.client.WebClientResponseException.create(WebClientResponseException.java:207) ~[spring-webflux-5.2.1.RELEASE.jar:5.2.1.RELEASE]
    Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
    |_ checkpoint ? 503 from GET lb://customer-service/customers [DefaultWebClient]
    |_ checkpoint ? Handler br.com.imobiliariaype.webportal.controller.CustomerController#findAll() [DispatcherHandler]
    |_ checkpoint ? org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain]
    |_ checkpoint ? org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain]
    |_ checkpoint ? HTTP GET "/v1/customers" [ExceptionHandlingWebHandler]
Stack trace:

这是来自的输出：`http://localhost:8761/eureka/apps`

<applications>
<versions__delta>1</versions__delta>
<apps__hashcode>UP_1_</apps__hashcode>
<application>
<name>CUSTOMER-SERVICE</name>
<instance>
<instanceId>WORKSTATION.mshome.net:customer-service:8060</instanceId>
<hostName>WORKSTATION.mshome.net</hostName>
<app>CUSTOMER-SERVICE</app>
<ipAddr>SOMEIP</ipAddr>
<status>UP</status>
<overriddenstatus>UNKNOWN</overriddenstatus>
<port enabled="true">8060</port>
<securePort enabled="false">443</securePort>
<countryId>1</countryId>
<dataCenterInfo class="com.netflix.appinfo.InstanceInfo$DefaultDataCenterInfo">
<name>MyOwn</name>
</dataCenterInfo>
<leaseInfo>
<renewalIntervalInSecs>30</renewalIntervalInSecs>
<durationInSecs>90</durationInSecs>
<registrationTimestamp>1577402896307</registrationTimestamp>
<lastRenewalTimestamp>1577403016236</lastRenewalTimestamp>
<evictionTimestamp>0</evictionTimestamp>
<serviceUpTimestamp>1577402895709</serviceUpTimestamp>
</leaseInfo>
<metadata>
<management.port>8060</management.port>
</metadata>
<homePageUrl>http://WORKSTATION.mshome.net:8060/</homePageUrl>
<statusPageUrl>http://WORKSTATION.mshome.net:8060/actuator/info</statusPageUrl>
<healthCheckUrl>http://WORKSTATION.mshome.net:8060/actuator/health</healthCheckUrl>
<vipAddress>customer-service</vipAddress>
<secureVipAddress>customer-service</secureVipAddress>
<isCoordinatingDiscoveryServer>false</isCoordinatingDiscoveryServer>
<lastUpdatedTimestamp>1577402896307</lastUpdatedTimestamp>
<lastDirtyTimestamp>1577402895638</lastDirtyTimestamp>
<actionType>ADDED</actionType>
</instance>
</application>
</applications>

还有一张来自 http://localhost:8761/ 的图片更改后：

来自服务发现的日志：

2019-12-26 22:46:14.690  INFO 20140 --- [      Thread-10] e.s.EurekaServerInitializerConfiguration : Started Eureka Server
2019-12-26 22:46:14.718  INFO 20140 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8761 (http) with context path ''
2019-12-26 22:46:14.719  INFO 20140 --- [           main] .s.c.n.e.s.EurekaAutoServiceRegistration : Updating port to 8761
2019-12-26 22:46:14.897  INFO 20140 --- [           main] b.c.i.s.ServiceDiscoveryApplication      : Started ServiceDiscoveryApplication in 4.839 seconds (JVM running for 5.348)
2019-12-26 22:46:26.374  INFO 20140 --- [nio-8761-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
2019-12-26 22:46:26.374  INFO 20140 --- [nio-8761-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
2019-12-26 22:46:26.379  INFO 20140 --- [nio-8761-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 5 ms
2019-12-26 22:46:26.530  INFO 20140 --- [nio-8761-exec-2] c.n.e.registry.AbstractInstanceRegistry  : Registered instance CUSTOMER-SERVICE/customer-service with status UP (replication=false)
2019-12-26 22:46:27.111  INFO 20140 --- [nio-8761-exec-3] c.n.e.registry.AbstractInstanceRegistry  : Registered instance CUSTOMER-SERVICE/customer-service with status UP (replication=true)

我正在处理的原始项目也可以在 GitHub 存储库中找到：

消费者 Microservice Customer 服务发现 Service Discovery 网关 API Gateway

Answer 1

它对我有用。不确定您的实施出了什么问题。

这是我尝试过的：

由于我不确定您的 customer-service 项目，我使用以下文件创建了自己的项目：

CustomerServiceApplication

@SpringBootApplication
@EnableDiscoveryClient
public class CustomerServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(CustomerServiceApplication.class, args);
    }

}

CustomerServiceController

@RestController("/customers")
public class CustomerServiceController {

    @GetMapping("/{id}")
    public String getId(@PathVariable("id") String id) {
        return "Customer";
    }
}

application.properties

server.port=8081
eureka.client.register-with-eureka=true
eureka.client.fetch-registry=true
spring.application.name=customer-service
eureka.instance.appname=customer-service

来到网关应用程序，我添加了以下文件：

CustomerWebService

@Service
public class CustomerWebService {

    private static final String CUSTOMERS_WITH_ID = "/customers/{id}";
    private static final String CUSTOMER_ROOT_ENDPOINT = "/customers";

    private String baseUrl = "lb://customer-service/customers";

    @LoadBalanced
    private final WebClient.Builder webClient;

    public CustomerWebService(WebClient.Builder webClient) {
        this.webClient = webClient;
    }

    public Mono<String> findById(String id) {
        return webClient.build()
                .get()
                .uri(baseUrl, id)
                .retrieve()
                .bodyToMono(String.class);
    }
}

LoadBalancers

@Component
public class LoadBalancers {

    @Bean
    public RouteLocator routeLocator(RouteLocatorBuilder routeLocatorBuilder) {
        return routeLocatorBuilder.routes()
                .route("customer-service", route -> route.path("/customers")
                        .uri("lb://customer-service"))
                .build();
    }

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

}

InstanceListener - 在 eureka 心跳上每 30 秒运行一次

@Component
public class InstanceListener implements ApplicationListener<HeartbeatEvent> {

    @Autowired
    private CustomerWebService customerWebService;

    @Override
    public void onApplicationEvent(HeartbeatEvent event) {
        Mono<String> result = customerWebService.findById("id");
        result.subscribe(
                value -> System.out.println(value),
                error -> error.printStackTrace()
        );
    }
}

application.properties

eureka.client.enabled=true
eureka.client.register-with-eureka=true
eureka.client.fetch-registry=true

每隔 30 秒，我就能看到对 customer-service 和 Gateway 的调用在控制台中显示 Customer 值。

完全按照我的方法进行尝试，看看它是否有效。让我知道。谢谢

Answer 2

我遇到了同样的问题，发现它恰好是因为 WebClient.Builder bean 中缺少 @LoadBalanced 注释。我在应用程序 Class 中定义如下：

@SpringBootApplication
@EnableEurekaClient
public class MovieCatalogueServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(MovieCatalogueServiceApplication.class, args);
    }

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

}

使用 Eureka 向 WebFlux 注册微服务时遇到问题

Trouble using Eureka to register a microservice with WebFlux

java

spring

spring-webflux

netflix-eureka

服务发现pom.xml

网关pom.xml（相同，来自服务发现pom.xml

这是来自的输出：http://localhost:8761/eureka/apps

来自服务发现的日志：

服务发现`pom.xml`

网关`pom.xml`（相同，来自服务发现`pom.xml`

这是来自的输出：`http://localhost:8761/eureka/apps`