3 微服务消费者者client注册到Eureka

Eureka Client注册到Eureka Server

• 可以通过RestTemplate实现RPC调用
• 一定要@loadBalance注解修饰的restTemplate才能实现服务名的调用，没有修饰的restTemplate是没有该功能的

Rest微服务工程构建

1、微服务提供者Module模块

新建cloud-consumer-order80，微服务消费者订单Module模块

2、改pom

父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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>springcloud</artifactId>
    <packaging>pom</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <modules>
        <module>cloud-eureka-server7001</module>
        <module>cloud-eureka-server7002</module>
        <module>cloud-provider-payment8001</module>
    </modules>
    <name>springcloud</name>
    <description>Demo project for Spring Boot</description>

    <!--统一管理jar包和版本-->
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>
        <mysql.version>8.0.18</mysql.version>
        <druid.version>1.1.16</druid.version>
        <druid.spring.boot.starter.version>1.1.10</druid.spring.boot.starter.version>
        <spring.boot.version>2.2.2.RELEASE</spring.boot.version>
        <spring.cloud.version>Hoxton.SR1</spring.cloud.version>
        <spring.cloud.alibaba.version>2.1.0.RELEASE</spring.cloud.alibaba.version>
        <mybatis.spring.boot.version>1.3.0</mybatis.spring.boot.version>
        <mybatis-spring-boot-starter.version>2.1.1</mybatis-spring-boot-starter.version>
        <hutool-all.version>5.1.0</hutool-all.version>
    </properties>

    <!--子模块继承后,提供作用:锁定版本+子module不用groupId和version-->
    <dependencyManagement>
        <dependencies>
            <!--springboot 2.2.2-->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring.boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--Spring cloud Hoxton.SR1-->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--Spring cloud alibaba 2.1.0.RELEASE-->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring.cloud.alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql.version}</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>${druid.version}</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>${druid.spring.boot.starter.version}</version>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis-spring-boot-starter.version}</version>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <finalName>cloud2020</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork>
                    <addResources>true</addResources>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

子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>springcloud</artifactId>
        <groupId>com.example</groupId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-consumer-order80</artifactId>

    <dependencies>
        <!--eureka client-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--图形化监控监控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--热部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </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>
        </dependency>
    </dependencies>
</project>

3、写yml

application.yml

server:
  port: 80

spring:
  application:
    name: cloud-order-service

eureka:
  client:
    register-with-eureka: true    # 是否将自己注册进eurekaServer，默认true
    fetchRegistry: true         #是否从EurekaServer抓取已有的注册信息，默认为true。单节点无所谓，集群必须设置为true才能配合ribbon使用负载均衡
    service-url:
      # 设置与Eureka Server交互的地址查询服务和注册服务都需要依赖这个地址
      #defaultZone: http://localhost:7001/eureka   #单机版
      defaultZone: http://eureka7001.com:7001/eureka,http://eureka7002.com:7002/eureka  #集群版

4、主启动

package com.example;

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

@SpringBootApplication
@EnableEurekaClient
public class OrderMain80 {
    public static void main(String[] args) {
        SpringApplication.run(OrderMain80.class, args);
    }
}

5、配置

• RestTemplate配置

package com.example.config;

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

@Configuration
public class ApplicationContextConfig {
    @Bean
    @LoadBalanced   //使用@LoadBalanced注解赋予RestTemplate负载均衡能力
    public RestTemplate getRestTemplate() {
        return new RestTemplate();
    }
}
//applicationContext.xml    <bean id="" class="">

6、业务类

• controller

package com.example.controller;

import com.example.entities.CommonResult;
import com.example.entities.Payment;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;

@RestController
@Slf4j
public class OrderController {
    //private static final String PAYMENT_URL = "http://127.0.0.1:8001";
    private static final String PAYMENT_URL = "http://CLOUD-PAYMENT-SERVICE";
    @Resource
    private RestTemplate restTemplate;

    @GetMapping("/consumer/payment/create")
    public CommonResult<Payment> create(Payment payment) {
        return restTemplate.postForObject(PAYMENT_URL + "/payment/create", payment, CommonResult.class);
    }

    @GetMapping("/consumer/payment/get/{id}")
    public CommonResult<Payment> getPayment(@PathVariable("id") Long id) {
        return restTemplate.getForObject(PAYMENT_URL + "/payment/get/" + id, CommonResult.class);
    }

    @GetMapping("/consumer/payment/create2")
    public CommonResult<Payment> create2(Payment payment) {
        return restTemplate.postForEntity(PAYMENT_URL + "/payment/create", payment, CommonResult.class).getBody();
    }

    @GetMapping("/consumer/payment/getForEntity/{id}")
    public CommonResult<Payment> getPayment2(@PathVariable("id") Long id) {
        ResponseEntity<CommonResult> entity = restTemplate.getForEntity(PAYMENT_URL + "/payment/get/" + id, CommonResult.class);
        if (entity.getStatusCode().is2xxSuccessful()) {
            return entity.getBody();
        } else {
            return new CommonResult<>(444, "操作失败");
        }
    }
}

• 测试：http://localhost/consumer/payment/getForEntity/3