7.Consul服务注册与发现

学习B站尚硅谷周阳老师SpringCloud的听课笔记

1. Consul简介

1.1是什么

1.2能干嘛

服务发现:提供HTTP和DNS两种发现方式
健康监测:支持多种协议，HTTP、TCP、Docker、Shell脚本定制化
KV存储:key , Value的存储方式
多数据中心:Consul支持多数据中心
可视化Web界面

官网：https://www.consul.io/intro/index.html
下载地址：https://www.consul.io/downloads.html
中文文档：https://www.springcloud.cc/spring-cloud-consul.html

1.3 安装并运行Consul

下载完成后只有一个consul.exe文件，硬盘路径下双击运行，查看版本信息

使用开发模式启动:consul agent -dev
通过以下地址可以访问Consul的首页：http://localhost:8500

2.新建Module支付服务provider8006

2.1 新建module cloud-providerconsul-payment8006

2.2 改pom

<?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">
    <parent>
        <artifactId>springcloud2020</artifactId>
        <groupId>com.atguigu.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-providerconsul-payment8006</artifactId>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-consul-discovery -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>com.atguigu.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>${project.version}</version>
        </dependency>


        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-devtools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-test -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

2.3 改yml

server:
  port: 8006

spring:
  application:
    name: consul-provider-payment
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        service-name: ${
    spring.application.name}

2.4 启动类与业务类

@SpringBootApplication
@EnableDiscoveryClient
public class PaymentMain8006 {
    
    public static void main(String[] args) {
    
        SpringApplication.run(PaymentMain8006.class,args);
    }
}

@RestController
@Slf4j
public class PaymentController {
    

    @Value("${server.port}")
    private String serverPort;

    @GetMapping(value = "/payment/consul")
    public String paymentConsul(){
    
        return "springcloud with consul: "+serverPort+"\t"+ UUID.randomUUID().toString();
    }
}

2.5验证测试

http://localhost:8006/payment/consul

3.新建Module消费服务order8006

3.1 新建Modulecloud-consumerconsul-order80

3.2 改pom

    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-consul-discovery -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>com.atguigu.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>${project.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-devtools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-test -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

3.3改yml

server:
  port: 80

spring:
  application:
    name: consul-consumer-order
  cloud:
    consul:
      host: localhost
      port: 8500
      discovery:
        service-name: ${
    spring.application.name}

3.4启动类与业务类

@SpringBootApplication
@EnableDiscoveryClient
public class OrderConsulMain80 {
    
    public static void main(String[] args) {
    
        SpringApplication.run(OrderConsulMain80.class,args);
    }
}

@Configuration
public class ApplicationContextConfig {
    
    @LoadBalanced
    @Bean
    public RestTemplate getRestTemplate(){
    
        return new RestTemplate();
    }
}

@RestController
@Slf4j
public class OrderConsulController {
    

    public static final String INVOME_URL = "http://consul-provider-payment";

    @Resource 
    private RestTemplate restTemplate;

    @GetMapping("/consumer/payment/consul")
    public String payment (){
    
      String result = restTemplate.getForObject(INVOME_URL+"/payment/consul",String.class);
      return result;
    }
}

3.5验证测试

http://localhost/consumer/payment/consul

4.三个注册中心异同点

4.1CAP理论

C:Consistency(强一致性)
A:Availability(可用性)
P:Partition tolerance(分区容错)
CAP理论关注粒度是数据，而不是整体系统设计的策略

4.2 三个注册中心异同点

4.2.1AP(Eureka)

4.2.2 CP(Zookeeper/Consul)