文章目录

一、consul的下载安装

consul的下载地址：​​https://www.consul.io/downloads​​

零基础带你快速入门consul-难道consul还能这样用？_xml


解压之后

零基础带你快速入门consul-难道consul还能这样用？_后端_02


在该路径下以cmd的方式打开

然后启动

consul agent -dev

零基础带你快速入门consul-难道consul还能这样用？_后端_03




二、框架搭建

1、创建父工程

零基础带你快速入门consul-难道consul还能这样用？_spring cloud_04


零基础带你快速入门consul-难道consul还能这样用？_后端_05


删除src目录

2、创建服务提供子模块(provider-consul-module)

零基础带你快速入门consul-难道consul还能这样用？_maven_06


零基础带你快速入门consul-难道consul还能这样用？_maven_07

3、创建服务消费子模块(consumer-consul-module)

零基础带你快速入门consul-难道consul还能这样用？_maven_06


零基础带你快速入门consul-难道consul还能这样用？_xml_09


零基础带你快速入门consul-难道consul还能这样用？_maven_10




二、代码准备

1、父工程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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.cloud</groupId>
    <artifactId>springcloud_all</artifactId>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>provider-consul-module</module>
        <module>consumer-consul-module</module>
    </modules>
    <packaging>pom</packaging>
    <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>4.13</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>
        <mysql.version>8.0.19</mysql.version>
        <druid.version>1.2.4</druid.version>
        <mybatis.spring.boot.version>2.1.4</mybatis.spring.boot.version>
        <druid.spring.boot.version>1.2.4</druid.spring.boot.version>
        <springfox-swagger-ui.version>2.9.2</springfox-swagger-ui.version>
        <springfox-swagger2.version>2.9.2</springfox-swagger2.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.4.3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--      spring-cloud 2020.0.2-->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>2020.0.2</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--      spring-cloud alibaba-->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2021.1</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>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis.spring.boot.version}</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>${druid.spring.boot.version}</version>
            </dependency>
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger-ui</artifactId>
                <version>${springfox-swagger-ui.version}</version>
            </dependency>
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger2</artifactId>
                <version>${springfox-swagger2.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <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>

2、服务提供子模块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_all</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.provider</groupId>
    <artifactId>provider-consul-module</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>
</project>

3、消费服务子模块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_all</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.consumer</groupId>
    <artifactId>consumer-consul-module</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>
</project>

4、提供服务模块和消费模块服务模块启动类

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

    public static void main(String[] args) {
        SpringApplication.run(ConsulConsumerApplication.class, args);
    }
}

@EnableDiscoveryClient注解的作用：能够让注册中心能够发现，扫描到微服务。

5、提供服务模块和消费模块服务模块application.yml文件

server:
  port: 8006
spring:
  cloud:
    consul:
      host: 127.0.0.1
      port: 8500
      discovery:
        service-name: ${spring.application.name}
  application:
    name: provider-consul-module
server:
  port: 80
spring:
  application:
    name: consumer-consul-module
  cloud:
    consul:
      host: 127.0.0.1
      port: 8500
      discovery:
        service-name: ${spring.application.name}

6、提供服务模块和消费模块服务模块controller代码

@RestController
@Slf4j
public class ProviderConsulController {
    @Value("${server.port}")
    private String serverPort;

    @GetMapping(value = "/provider/test")
    public String test() {
        return "提供服务模块服务端口号为:" + serverPort + "《--------------》" + UUID.randomUUID().toString();
    }
}
@RestController
public class ConsumerConsulController {
    private static final String INVOKE_URL = "http://provider-consul-module";

    @Resource
    private RestTemplate restTemplate;

    @GetMapping(value = "/consumer/test")
    public String getData() {

        return restTemplate.getForObject(INVOKE_URL + "/provider/test", String.class);
    }
}

7、RestTemplate详解及其配置

RestTemplate是spring封装的一个服务端远程HTTP请求工具，支持常见的Rest请求（get、post等）
简单了说就是用来远程调用的，因为你订单模块是一个服务，消费模块又是一个单独的服务，两个服务端的端口号要进行交互，所以就有了RestTemplate

当然要注入RestTemplate(注意是在消费模块配置，因为是消费服务调用提供服务模块）

@Configuration
public class ApplicationContextConfig {

    @Bean
    @LoadBalanced
    public RestTemplate AutoRestTemplate() {
        return new RestTemplate();
    }
}




三、测试

启动提供服务模块和消费服务模块（注意一定要开启zookeeper服务，顺便进入zookeeper客户端）

零基础带你快速入门consul-难道consul还能这样用？_后端_11


访问http://localhost:8500，你可以看到consul的客户端界面（然后我们启动的两个服务已经成功注册进consul）

零基础带你快速入门consul-难道consul还能这样用？_后端_12


接口测试

零基础带你快速入门consul-难道consul还能这样用？_spring_13


成功！



四、灵魂拷问？为什么需要注册中心

我们在微服务中首先需要面对的问题是服务之间如何进行通信呢？在单体架构中，我们只要将服务的接口暴露，然后通过http请求即可，微服务当然也可以这样。
问题是我们请求的url是固定的，单体服务为我们还可以很快的修改；一旦有大量的服务那就需要我们手动维护服务接口，配置负载均衡；服务宕机后，如何及时下线呢？
总而言之注册中心必不可少（至少当前时代是这样）。