前言

上篇咱们讲到如何应用k8s搭建nacos，这篇就来讲讲微服务如何通过搭建好的nacos服务注册和配置。

操作

A服务、B服务，A应用Feign调用B服务外面办法。

A、B服务引入相干依赖包，

• springcloud版本：2020.0.0
• springboot版本：2.4.2

• alibaba版本：2021.1

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.4.2</version>
  </parent>
  <properties>
    <java.version>1.8</java.version>
    <spring-boot.version>2.4.2</spring-boot.version>
    <spring-cloud.version>2020.0.0</spring-cloud.version>
    <spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version>
  </properties>
  <dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>${spring-boot.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <!-- spring cloud 依赖 -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>${spring-cloud.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <!-- spring cloud alibaba 依赖 -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-dependencies</artifactId>
            <version>${spring-cloud-alibaba.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
  </dependencyManagement>
  <dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-loadbalancer</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-bootstrap</artifactId>
    </dependency>
  </dependencies>
  

  A、B服务注册和配置到Nacos服务的bootstrap.yml文件：

  spring:
  application:
    name: a-service # b-service
  profiles:
    active: test
  cloud:
    nacos:
      #注册A、B服务到Nacos
      discovery:
        server-addr: http://nacos-headless.default.svc.cluster.local:8848
        namespace: xxx-xxx-xxx-xxx
        service: a-service # b-service
      #配置A、B服务到Nacos
      config:
        server-addr: http://nacos-headless.default.svc.cluster.local:8848
        file-extension: yaml
        prefix: a-service # b-service
        namespace: xxx-xxx-xxx-xxx
  server:
  port: a-port # b-port

能够间接在Nacos下面创立A、B服务的配置文件：

B服务办法：

@SpringBootApplication
@EnableDiscoveryClient
@RestController
@RefreshScope
public class BServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(BServiceApplication.class, args);
    }
    
    @Value("${server.port}")
    String port;

    @GetMapping("/hi")
    public String hi(@RequestParam(value = "name", defaultValue = "forezp",required = false) String name) {
        return "hello " + name + ", i'm provider ,my port:" + port;

    }
}

A服务想要调用B服务办法，首先创立BFeignClient类：

@FeignClient("b-service")
public interface BFeignClient {
    @GetMapping("/hi")
    String hi(@RequestParam(value = "name", defaultValue = "forezp", required = false) String name);
}

接着，创立调用的办法：

@SpringBootApplication
@RestController
@EnableDiscoveryClient
@EnableFeignClients
@RefreshScope
public class AServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(AServiceApplication.class, args);
    }
    
    @Autowired
    BFeignClient bFeignClient;

    @GetMapping("/hi-feign")
    public String hiFeign(){
        return bFeignClient.hi("feign");
    }
}

运行起来，看看两个服务是否在Nacos注册胜利，如图所示：

注册胜利之后，咱们就能够测试A服务调用B服务是否胜利：

总结

1、因为咱们应用的是service headless，所以咱们要应用dns查找nacos，默认是你的service name 加上固定写法：default.svc.cluster.local，我的nacos service name是nacos-headless，即：nacos-headless.default.svc.cluster.local

2、因为nacos应用的是最新版本，所以discovery要加service属性，否则报错

discovery:
  server-addr: http://nacos-headless.default.svc.cluster.local:8848
  namespace: xxx-xxx-xxx-xxx
  service: a-service  # b-service

3、因为应用的是springcloud:2020.0版本，所以pom引入bootstrap包，否则bootstrap.yml不起作用

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-bootstrap</artifactId>
</dependency>

援用

SpringCloud 2020版本教程1：应用nacos作为注册核心和配置核心
k8s集群外部怎么通过dns域名使得业务零碎注册到nacos集群阐明-方法论，其余通过域名拜访服务一样的
k8s部署nacos 3各节点….N各节点均可 集群
Kubernetes Nacos