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有了 Kubernetes 注册发现,我们就可以抛弃 Eureka Server。
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>cn.netkiller</groupId> <artifactId>kubernetes</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>pom</packaging> <name>kubernetes</name> <url>http://www.netkiller.cn</url> <description>Spring Cloud with Kubernetes</description> <organization> <name>Netkiller Spring Cloud 手札</name> <url>http://www.netkiller.cn</url> </organization> <developers> <developer> <name>Neo</name> <email>netkiller@msn.com</email> <organization>Netkiller Spring Cloud 手札</organization> <organizationUrl>http://www.netkiller.cn</organizationUrl> <roles> <role>Author</role> </roles> </developer> </developers> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <spring-cloud.version>Hoxton.SR8</spring-cloud.version> <docker.registry>registry.netkiller.cn:5000</docker.registry> <docker.registry.name>netkiller</docker.registry.name> <docker.image>mcr.microsoft.com/java/jre:15-zulu-alpine</docker.image> </properties> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.3.4.RELEASE</version> <relativePath /> </parent> <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> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> </dependencies> <modules> <module>service</module> <module>ConfigMaps</module> <module>provider</module> <module>consumer</module> </modules> </project>
<?xml version="1.0"?> <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>cn.netkiller</groupId> <artifactId>kubernetes</artifactId> <version>0.0.1-SNAPSHOT</version> </parent> <groupId>cn.netkiller</groupId> <artifactId>provider</artifactId> <version>0.0.1-SNAPSHOT</version> <name>provider</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-kubernetes</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-webflux</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <plugin> <artifactId>maven-surefire-plugin</artifactId> <configuration> <skip>true</skip> </configuration> </plugin> <plugin> <groupId>com.spotify</groupId> <artifactId>docker-maven-plugin</artifactId> <version>1.2.2</version> <configuration> <imageName>${docker.registry}/${docker.registry.name}/${project.artifactId}</imageName> <baseImage>${docker.image}</baseImage> <maintainer>netkiller@msn.com</maintainer> <volumes>/tmp</volumes> <workdir>/srv</workdir> <exposes>8080</exposes> <env> <JAVA_OPTS>-server -Xms128m -Xmx256m</JAVA_OPTS> </env> <entryPoint>["sh", "-c", "java ${JAVA_OPTS} -jar /srv/${project.build.finalName}.jar ${SPRING_OPTS}"]</entryPoint> <resources> <resource> <targetPath>/srv</targetPath> <directory>${project.build.directory}</directory> <include>${project.build.finalName}.jar</include> </resource> </resources> <!-- <image>${docker.image.prefix}/${project.artifactId}</image> --> <!-- <newName>${docker.image.prefix}/${project.artifactId}:${project.version}</newName> --> <!-- <serverId>docker-hub</serverId> --> <registryUrl>http://${docker.registry}/v2/</registryUrl> <imageTags> <!-- <imageTag>${project.version}</imageTag> --> <imageTag>latest</imageTag> </imageTags> </configuration> </plugin> </plugins> </build> </project>
注意:这里必须使用 @EnableDiscoveryClient 注解,不能使用 @EnableEurekaClient。
他们的区别是 @EnableEurekaClient 只能注册到 Eureka Server,而 @EnableDiscoveryClient 不仅可以注册进 Eureka Server 还能注册到 ZooKeeper,Consul,Kubernetes 等等......
package cn.netkiller.provider; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; @SpringBootApplication @EnableDiscoveryClient public class ProviderApplication { public static void main(String[] args) { System.out.println("Hello World!"); SpringApplication.run(ProviderApplication.class, args); } }
package cn.netkiller.provider.controller; import java.net.InetAddress; import java.net.UnknownHostException; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cloud.client.discovery.DiscoveryClient; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import lombok.extern.slf4j.Slf4j; @RestController @Slf4j public class ProviderController { @Autowired private DiscoveryClient discoveryClient; @GetMapping("/") public String index() { return "Hello world!!!"; } @GetMapping("/ping") public String ping() { try { return InetAddress.getLocalHost().getHostName(); } catch (UnknownHostException e) { return "Pong"; } } @GetMapping("/services") public List<String> services() { return this.discoveryClient.getServices(); } }
@GetMapping("/services") 可以返回注册中心已经注册的服务。
src/main/resource/application.properties 配置文件
spring.application.name=provider server.port=8080
Pod 启动后会以 spring.application.name 设置的名字注册到注册中心,Openfeign 将改名字访问微服务。
apiVersion: v1 kind: Service metadata: name: provider labels: app.kubernetes.io/name: provider spec: type: ClusterIP ports: - port: 8080 targetPort: 8080 protocol: TCP name: http selector: app.kubernetes.io/name: provider --- apiVersion: apps/v1 kind: Deployment metadata: name: provider labels: app.kubernetes.io/name: provider spec: replicas: 1 selector: matchLabels: app.kubernetes.io/name: provider template: metadata: labels: app.kubernetes.io/name: provider app.kubernetes.io/instance: sad-markhor spec: containers: - name: provider image: registry.netkiller.cn:5000/netkiller/provider #imagePullPolicy: IfNotPresent ports: - name: http containerPort: 8080 protocol: TCP env: - name: "KUBERNETES_NAMESPACE" valueFrom: fieldRef: fieldPath: "metadata.namespace"
<?xml version="1.0"?> <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>cn.netkiller</groupId> <artifactId>kubernetes</artifactId> <version>0.0.1-SNAPSHOT</version> </parent> <groupId>cn.netkiller</groupId> <artifactId>consumer</artifactId> <version>0.0.1-SNAPSHOT</version> <name>consumer</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-kubernetes</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-kubernetes-ribbon</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-webflux</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <plugin> <artifactId>maven-surefire-plugin</artifactId> <configuration> <skip>true</skip> </configuration> </plugin> <plugin> <groupId>com.spotify</groupId> <artifactId>docker-maven-plugin</artifactId> <version>1.2.2</version> <configuration> <imageName>${docker.registry}/${docker.registry.name}/${project.artifactId}</imageName> <baseImage>${docker.image}</baseImage> <maintainer>netkiller@msn.com</maintainer> <volumes>/tmp</volumes> <workdir>/srv</workdir> <exposes>8080</exposes> <env> <JAVA_OPTS>-server -Xms128m -Xmx256m</JAVA_OPTS> </env> <entryPoint>["sh", "-c", "java ${JAVA_OPTS} -jar /srv/${project.build.finalName}.jar ${SPRING_OPTS}"]</entryPoint> <resources> <resource> <targetPath>/srv</targetPath> <directory>${project.build.directory}</directory> <include>${project.build.finalName}.jar</include> </resource> </resources> <!-- <image>${docker.image.prefix}/${project.artifactId}</image> --> <!-- <newName>${docker.image.prefix}/${project.artifactId}:${project.version}</newName> --> <!-- <serverId>docker-hub</serverId> --> <registryUrl>http://${docker.registry}/v2/</registryUrl> <imageTags> <!-- <imageTag>${project.version}</imageTag> --> <imageTag>latest</imageTag> </imageTags> </configuration> </plugin> </plugins> </build> </project>
package cn.netkiller.consumer; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; import org.springframework.cloud.openfeign.EnableFeignClients; @SpringBootApplication @EnableDiscoveryClient @EnableFeignClients public class ConsumerApplication { public static void main(String[] args) { System.out.println("Hello World!"); SpringApplication.run(ConsumerApplication.class, args); } }
package cn.netkiller.consumer.controller; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cloud.client.ServiceInstance; import org.springframework.cloud.client.discovery.DiscoveryClient; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import cn.netkiller.consumer.feign.ProviderClient; import lombok.extern.slf4j.Slf4j; @RestController @Slf4j public class ConsumerController { @Autowired private DiscoveryClient discoveryClient; @Autowired private ProviderClient providerClient; @GetMapping("/") public String index() { return "Consumer OK\r\n"; } @GetMapping("/service") public Object getClient() { return discoveryClient.getServices(); } @GetMapping("/instance") public List<ServiceInstance> getInstance(String instanceId) { return discoveryClient.getInstances(instanceId); } @GetMapping("/ping") public String ping() { return OperationResponse.builder().status(true).data(providerClient.ping()).build(); } }
@GetMapping("/ping") 将经过注册中心,获取到可用的服务,运行后从微服务返回结果。
package cn.netkiller.consumer.controller; public class OperationResponse { public boolean status = false; public String data = ""; public static OperationResponse builder() { // TODO Auto-generated method stub return new OperationResponse(); } public OperationResponse status(boolean status) { this.status = status; return this; } public OperationResponse data(String data) { this.data = data; return this; } public String build() { return String.format("Status: %s, Data: %s", this.status, this.data); } }
package cn.netkiller.consumer.feign; import org.springframework.cloud.openfeign.FeignClient; import org.springframework.stereotype.Component; import org.springframework.web.bind.annotation.GetMapping; @FeignClient(name = "provider", fallback = ProviderClientFallback.class) public interface ProviderClient { @GetMapping("/ping") String ping(); } @Component class ProviderClientFallback implements ProviderClient { @Override public String ping() { return "Error"; } }
src/main/resource/application.properties 配置文件
spring.application.name=consumer server.port=8080 provider.ribbon.KubernetesNamespace=default provider.ribbon.NFLoadBalancerRuleClassName=com.netflix.loadbalancer.RandomRule
apiVersion: v1 kind: Service metadata: name: consumer labels: app.kubernetes.io/name: consumer spec: type: NodePort ports: - port: 8080 nodePort: 30080 protocol: TCP name: http selector: app.kubernetes.io/name: consumer --- apiVersion: apps/v1 kind: Deployment metadata: name: consumer labels: app.kubernetes.io/name: consumer spec: replicas: 1 selector: matchLabels: app.kubernetes.io/name: consumer template: metadata: labels: app.kubernetes.io/name: consumer spec: containers: - name: consumer image: registry.netkiller.cn:5000/netkiller/consumer #imagePullPolicy: IfNotPresent ports: - name: http containerPort: 8080 protocol: TCP
编译,打包,构建Docker镜像
iMac:provider neo$ mvn package docker:build iMac:consumer neo$ mvn package docker:build
推送镜像
iMac:spring-cloud-kubernetes neo$ docker images | grep registry.netkiller.cn registry.netkiller.cn:5000/netkiller/consumer latest 63921dc9b81d 27 seconds ago 238MB registry.netkiller.cn:5000/netkiller/provider latest fbcc6b3a91ef 4 minutes ago 221MB registry.netkiller.cn:5000/netkiller/configmaps latest 93280aec434f 23 hours ago 219MB iMac:spring-cloud-kubernetes neo$ docker push registry.netkiller.cn:5000/netkiller/consumer The push refers to repository [registry.netkiller.cn:5000/netkiller/consumer] 51c839989a66: Pushed 7c1edc21f93f: Pushed 50644c29ef5a: Pushed latest: digest: sha256:2591686cfc63888f3b97ca1e950205b58a47b3d3c618242465baa0796cf7e056 size: 952 iMac:spring-cloud-kubernetes neo$ docker push registry.netkiller.cn:5000/netkiller/provider The push refers to repository [registry.netkiller.cn:5000/netkiller/provider] 47eb1c86b415: Pushed 7c1edc21f93f: Mounted from netkiller/consumer 50644c29ef5a: Mounted from netkiller/consumer latest: digest: sha256:42cdeb63cd67a5edf9e769538878a0c8f18048bcde1ef9ba22d58766afa2d52d size: 952 iMac:spring-cloud-kubernetes neo$ curl -s http://registry.netkiller.cn:5000/v2/_catalog | jq { "repositories": [ "netkiller/configmaps", "netkiller/consumer", "netkiller/provider" ] }
将 provider 和 consumer 应用部署到 Kubernetes
iMac:spring-cloud-kubernetes neo$ kubectl create -f provider/src/main/kubernetes/provider.yaml service/provider created deployment.apps/provider created iMac:spring-cloud-kubernetes neo$ kubectl create -f consumer/src/main/kubernetes/consumer.yaml service/consumer created deployment.apps/consumer created
查看 consumer 端口
iMac:spring-cloud-kubernetes neo$ minikube service list |----------------------|---------------------------|--------------|----------------------------| | NAMESPACE | NAME | TARGET PORT | URL | |----------------------|---------------------------|--------------|----------------------------| | default | config | http/8080 | http://192.168.64.12:30662 | | default | consumer | http/8080 | http://192.168.64.12:30080 | | default | kubernetes | No node port | | default | provider | No node port | | kube-system | kube-dns | No node port | | kubernetes-dashboard | dashboard-metrics-scraper | No node port | | kubernetes-dashboard | kubernetes-dashboard | No node port | |----------------------|---------------------------|--------------|----------------------------|
测试 provider 是否工作正常
$ curl -s http://10.10.0.121:8080/ping provider-54875bf44-4gf49 $ curl -s http://10.10.0.121:8080/services |jq [ "config", "kubernetes", "provider" ]
查看 consumer 是否已经注册成功
iMac:spring-cloud-kubernetes neo$ curl -s http://192.168.64.12:30080/service |jq [ "config", "consumer", "kubernetes", "provider" ] iMac:spring-cloud-kubernetes neo$ curl http://192.168.64.12:30080/ping Status: true, Data: provider-54875bf44-4gf49
增加 provider 节点,然后反复请求可以看到返回不同节点的主机名
iMac:spring-cloud-kubernetes neo$ kubectl scale deployment provider --replicas=3 deployment.apps/provider scaled iMac:spring-cloud-kubernetes neo$ curl -s http://192.168.64.12:30080/ping Status: true, Data: provider-54875bf44-8vs72 iMac:spring-cloud-kubernetes neo$ curl -s http://192.168.64.12:30080/ping Status: true, Data: provider-54875bf44-4gf49i
测试完毕销毁服务
iMac:spring-cloud-kubernetes neo$ kubectl delete -f consumer/src/main/kubernetes/consumer.yaml service "consumer" deleted deployment.apps "consumer" deleted iMac:spring-cloud-kubernetes neo$ kubectl delete -f provider/src/main/kubernetes/provider.yaml service "provider" deleted deployment.apps "provider" deleted