Spring Cloud Kubernetes Demo

之前项目中的服务发现和服务配置用的Nacos, 现在需求是去掉Nacos, 换成 Kubernetes

背景交代清楚了, 说下利用Kubernetes来实现服务发现和服务配置, 两大功能的策略...

Kubernetes 给每个 service 提供了稳定的网络标识, 我们可以用来做为 转发标识
利用 ConfigMap 来实现服务配置的功能

并且兼顾了开发环境与Kubernetes环境

# Pom.xml 根据环境, 区分环境变量

<properties>
    <demo-gateway.port>28080</demo-gateway.port>
    <demo-consumer.port>28081</demo-consumer.port>
    <demo-provider.port>28082</demo-provider.port>
</properties>

<profiles>
    <profile>
        <id>dev</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <properties>
            <config.file.path>~/development/workspace/idea/spring-cloud-kubernetes-demo/config</config.file.path>
            <service-demo-gateway>http://127.0.0.1:${demo-gateway.port}</service-demo-gateway>
            <service-demo-consumer>http://127.0.0.1:${demo-consumer.port}</service-demo-consumer>
            <service-demo-provider>http://127.0.0.1:${demo-provider.port}</service-demo-provider>
        </properties>
    </profile>

    <profile>
        <id>kubernetes</id>
        <activation>
            <activeByDefault>false</activeByDefault>
        </activation>
        <properties>
            <config.file.path>/opt/app/config</config.file.path>
            <!-- Kubernetes native service discovery -->
            <service-demo-gateway>http://demo-gateway-service:${demo-provider.port}</service-demo-gateway>
            <service-demo-consumer>http://demo-consumer-service:${demo-consumer.port}</service-demo-consumer>
            <service-demo-provider>http://demo-provider-service:${demo-provider.port}</service-demo-provider>
        </properties>
    </profile>
</profiles>

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demo-gateway-service, demo-consumer-service, demo-provider-service 这些稳定网络标识, 后面再说怎么创建的, 先说是怎么用的吧

用到网络标识的地方, 有两处:

gateway: 路由转发
openfeign: 远程调用

gateway 配置

# 后面考虑写到公共包里去
demo: 
  service:
    demo-gateway: @service-demo-gateway@
    demo-consumer: @service-demo-consumer@
    demo-provider: @service-demo-provider@

spring:
  application:
    name: demo-gateway
  cloud:
    gateway:
      discovery:
        locator:
          enabled: true
          url-expression: uri # uri 转发
      routes:
        - id: demo-consumer
          uri: ${demo.service.demo-consumer} # 转发到咱们配置好的URL上(稳定的唯一标识or本地地址)
          predicates:
            - Path=/api/v1/consumer/**
          filters:
            - StripPrefix=3
        - id: demo-provider
          uri: ${demo.service.demo-provider}
          predicates:
            - Path=/api/v1/provider/**
          filters:
            - StripPrefix=3

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openfeign client

package com.striveonger.demo.remote;


import com.striveonger.demo.RemoteHelloService;
import org.springframework.cloud.openfeign.FeignClient;

/**
 * @author Mr.Lee
 * @description:
 * @date 2024-05-13 18:43
 */
@FeignClient(name = "demo-provider", url = "${demo.service.demo-provider}") // 这也是引用了之前配置的稳定的网络标识
public interface RemoteHelloServiceClient extends RemoteHelloService {

}

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# demo-gateway.yaml

---
apiVersion: "apps/v1"
kind: "Deployment"
metadata:
  namespace: "demo"
  name: "demo-gateway-deployment"
  labels:
    app: "demo-gateway"
    version: "1.0.0"
spec:
  replicas: 1 # 设置副本数
  selector:
    matchLabels: # 定义deploy匹配pod规则
      app: "demo-gateway"
  template: # 定义pod模版的元数据
    metadata:
      namespace: "demo"
      name: "demo-gateway-pod"
      labels:
        app: "demo-gateway" # 用于deploy匹配
    spec: # 定义容器
      containers:
      - name: "demo-gateway"
        image: "demo-service:1.0.0"
        resources: # 定义系统资源
          limits:
            cpu: "2"
            memory: "512M"
          requests:
            cpu: "2"
            memory: "512M"
        ports:
        - containerPort: 28080
          protocol: "TCP"
        env: # 定义环境变量
        - name: "APP_NAME"
          value: "demo-gateway"
        volumeMounts: # 关联到的 ConfigMap, 中key做为文件名, value, 做为文件的内容, 挂载到指定目录
          - name: "demo-config" # 关联下面 volumes 中定义的ConfigMap名称
            mountPath: "/opt/app/config" # 关联到的 ConfigMap, 在Pod中的挂载目录
      volumes:
        - name: "demo-config" # 定义挂在的ConfigMap的名称
          configMap:
            name: "demo-config" # 关联 ConfigMap 的名称
      restartPolicy: "Always" # 重启策略
---
apiVersion: "v1"
kind: "Service"
metadata:
  namespace: "demo"
  name: "demo-gateway-service" # 设置服务名(稳定的网络标识)
  labels:
    app: "demo-gateway"
spec:
  ports:
    - protocol: "TCP"
      port: 28080
      targetPort: 28080
  selector:
    app: "demo-gateway" # 用于 service 匹配 pod
  type: "ClusterIP"

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demo-consumer-service, demo-provider-service 的配置大差不差.....

容器内查看配置文件

导入配置文件

server:
  port: @demo-provider.port@


spring:
  application:
    name: demo-provider
  main:
    allow-bean-definition-overriding: true
  config:
    import: # 导入配置文件
      - file://@config.file.path@/demo-commons.yaml
      - file://@config.file.path@/demo-provider.yaml

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Striveonger