【SpringCloud】整合Consul+OpenFeign实现微服务+负载均衡（上）

一、服务架构

service-common 核心公共功能服务

service-provider 服务提供者微服务

service-consumer 服务消费者微服务

主要特性：

1. springcloud+consul+openfeign+ribbion

2. 基于feign_client + rest_template 两种微服务调用方式

二、父pom.xml文件

pom.xml

<?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>org.example</groupId>
    <artifactId>springcloud-consul</artifactId>
    <packaging>pom</packaging>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>service-common</module>
        <module>service-provider</module>
        <module>service-consumer</module>
    </modules>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>
        <!-- SpringBoot监控 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-config</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

三、公共服务service-common代码

pom.xml文件

springcloud-consul/service-common/pom.xml

<?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-consul</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>service-common</artifactId>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
</project>

springcloud-consul/service-common/src/main/java/com/example/common/model/UserModel.java

package com.example.common.model;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class UserModel implements Serializable {
    private String username;
    private int age;
    private String address;
    private String job;
}

springcloud-consul/service-common/src/main/java/com/example/common/service/UserService.java

package com.example.common.service;
import com.example.common.model.UserModel;
import java.util.List;
public interface UserService {
    List<UserModel> findAll();
    UserModel findById(int id);
    String port();
}

四、服务提供者service-provider代码

pom.xml文件

<?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-consul</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>service-provider</artifactId>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>service-common</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <includeSystemScope>true</includeSystemScope>
                    <mainClass>com.example.provider.ConsulProviderApplication</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

springcloud-consul/service-provider/src/main/resources/application.yml

spring:
  application:
    name: service-provider
  profiles:
    active: dev
  cloud:
    consul:
      # 服务发现配置
      discovery:
        # 启用服务发现
        enabled: true
        # 启用服务注册
        register: true
        # 服务停止时取消注册
        deregister: true
        # 表示注册时使用IP而不是hostname
        prefer-ip-address: true
        # 执行监控检查的频率
        health-check-interval: 30s
        # 设置健康检查失败多长时间后，取消注册
        health-check-critical-timeout: 30s
        # 健康检查的路径
        health-check-path: /actuator/info
        # 服务注册标识，格式为：应用名称+服务器IP+端口
        instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${server.port}
server:
  port: 8011

springcloud-consul/service-provider/src/main/resources/bootstrap.yml

# bootstrap.yml
# consul 使用动态配置，必须在bootstrap.yml中配置好动态配置项目的配置
spring:
  cloud:
    consul:
      host: localhost
      port: 8500
      #enabled将此值设置为“false”禁用Consul配置
      config:
        enabled: true   #默认是true --
        format: YAML    # 表示consul上面文件的格式 有四种 YAML PROPERTIES KEY-VALUE FILES
        data-key: data  #表示consul上面的KEY值(或者说文件的名字) 默认是data
        # watch选项为配置监视功能，主要监视配置的改变
        watch:
          enabled: true
          delay: 10000
          wait-time: 30

springcloud-consul/service-provider/src/main/java/com/example/provider/service/impl/UserServiceImpl.java

package com.example.provider.service.impl;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import java.util.Arrays;
import java.util.List;
@Service
public class UserServiceImpl implements UserService {
    @Value("${server.port}")
    int port;
    @Override
    public List<UserModel> findAll() {
        return Arrays.asList(
                new UserModel("张三", 22, "西安", "Java开发"),
                new UserModel("李四", 24, "深圳", "总经理助理"),
                new UserModel("王五", 56, "上海", "HR"),
                new UserModel("赵六", 12, "广州", "PHP开发"),
                new UserModel("宋七", 42, "重庆", "运营")
        );
    }
    @Override
    public UserModel findById(int id) {
        return new UserModel("lucy", 44, "西雅图", "董事长");
    }
    @Override
    public String port() {
        return "Port: " + port;
    }
}

springcloud-consul/service-provider/src/main/java/com/example/provider/web/HiController.java

package com.example.provider.web;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HiController {
    @Value("${server.port}")
    String port;
    @GetMapping("/hi")
    public String home(@RequestParam String name) {
        return "hi "+name+",i am from port:" +port;
    }
    @GetMapping("/port")
    public String port() {
        return port;
    }
}

springcloud-consul/service-provider/src/main/java/com/example/provider/web/UserController.java

package com.example.provider.web;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
@RequestMapping("api/user")
public class UserController {
    @Autowired
    UserService userService;
    @GetMapping("list")
    public List<UserModel> findAll() {
        return userService.findAll();
    }
    @GetMapping("get")
    public UserModel findById(int id) {
        return userService.findById(id);
    }
    @GetMapping("port")
    public String port() {
        return userService.port();
    }
}

springcloud-consul/service-provider/src/main/java/com/example/provider/ConsulProviderApplication.java

package com.example.provider;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.context.annotation.ComponentScan;
@SpringBootApplication
@ComponentScan(basePackages = {"com.example"})
@EnableDiscoveryClient
public class ConsulProviderApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConsulProviderApplication.class, args);
        System.out.println(".....................................");
        System.out.println("....Provider Application started.....");
        System.out.println(".....................................");
    }
}

五、服务消费者service-consumer代码

pom.xml文件

<?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-consul</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>service-consumer</artifactId>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>service-common</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <includeSystemScope>true</includeSystemScope>
                    <mainClass>com.example.consumer.ConsulConsumerApplication</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

springcloud-consul/service-consumer/src/main/java/com/example/consumer/feign/HiFeign.java

package com.example.consumer.feign;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
@FeignClient(value = "service-provider", contextId = "hi")
public interface HiFeign {
    @GetMapping(value = "/hi")
    String sayHiFromFeign(@RequestParam(value = "name") String name);
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/feign/UserFeign.java

package com.example.consumer.feign;
import com.example.common.model.UserModel;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import java.util.List;
@FeignClient(value = "service-provider", contextId = "user")
@RequestMapping("api/user")
public interface UserFeign {
    @GetMapping(value = "list")
    List<UserModel> findAll();
    @GetMapping(value = "get")
    UserModel findById(@RequestParam(value = "id") int id);
    @GetMapping(value = "port")
    String getPort();
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/service/HiService.java

package com.example.consumer.service;
import com.example.consumer.feign.HiFeign;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class HiService {
    @Autowired
    HiFeign hiFeign;
    public String sayHi(String name) {
        return hiFeign.sayHiFromFeign(name);
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/service/impl/UserFeignServiceImpl.java

package com.example.consumer.service.impl;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import com.example.consumer.feign.UserFeign;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class UserFeignServiceImpl implements UserService {
    @Autowired
    UserFeign userFeign;
    @Override
    public List<UserModel> findAll() {
        return userFeign.findAll();
    }
    @Override
    public UserModel findById(int id) {
        return userFeign.findById(id);
    }
    @Override
    public String port() {
        return userFeign.getPort();
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/service/impl/UserRestServiceImpl.java

package com.example.consumer.service.impl;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;
import java.util.List;
@Service
public class UserRestServiceImpl implements UserService {
    @Autowired
    RestTemplate restTemplate;
    @Override
    public List<UserModel> findAll() {
        ResponseEntity<List<UserModel>> responseEntity = restTemplate.exchange(
                "http://service-provider/api/user/list",
                HttpMethod.GET,
                null,
                new ParameterizedTypeReference<List<UserModel>>() {
                });
        return responseEntity.getBody();
    }
    @Override
    public UserModel findById(int id) {
        ResponseEntity<UserModel> responseEntity = restTemplate.exchange(
                "http://service-provider/api/user/get?id=" + id,
                HttpMethod.GET,
                null,
                new ParameterizedTypeReference<UserModel>() {
                });
        return responseEntity.getBody();
    }
    @Override
    public String port() {
        ResponseEntity<String> responseEntity = restTemplate.exchange(
                "http://service-provider/api/user/port",
                HttpMethod.GET,
                null,
                new ParameterizedTypeReference<String>() {
                });
        return responseEntity.getBody();
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/web/HiController.java

package com.example.consumer.web;
import com.example.consumer.service.HiService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HiController {
    @Autowired
    HiService hiService;
    @Value("${server.port}")
    String port;
    @GetMapping("/hi")
    public String home(@RequestParam String name) {
        return hiService.sayHi(name);
    }
    @GetMapping("/port")
    public String port() {
        return port;
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/web/UserFeignController.java

package com.example.consumer.web;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import com.example.consumer.service.impl.UserFeignServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
@RequestMapping("feign-api/user")
public class UserFeignController implements UserService {
    @Autowired
    UserFeignServiceImpl userService;
    @Override
    @GetMapping("/list")
    public List<UserModel> findAll() {
        return userService.findAll();
    }
    @Override
    @GetMapping("/get")
    public UserModel findById(int id) {
        return userService.findById(id);
    }
    @Override
    @GetMapping("port")
    public String port() {
        return userService.port();
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/web/UserRestController.java

package com.example.consumer.web;
import com.example.common.model.UserModel;
import com.example.common.service.UserService;
import com.example.consumer.service.impl.UserRestServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
@RequestMapping("rest-api/user")
public class UserRestController implements UserService {
    @Autowired
    UserRestServiceImpl userRestService;
    @GetMapping("list")
    public List<UserModel> findAll() {
        return userRestService.findAll();
    }
    @GetMapping("get")
    public UserModel findById(int id) {
        return userRestService.findById(id);
    }
    @GetMapping("port")
    public String port() {
        return userRestService.port();
    }
}

springcloud-consul/service-consumer/src/main/java/com/example/consumer/ConsulConsumerApplication.java

package com.example.consumer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.web.client.RestTemplate;
@SpringBootApplication
@ComponentScan(basePackages = {"com.example"})
@EnableDiscoveryClient
@EnableFeignClients
public class ConsulConsumerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConsulConsumerApplication.class, args);
        System.out.println(".....................................");
        System.out.println("....Consumer Application started.....");
        System.out.println(".....................................");
    }
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

springcloud-consul/service-consumer/src/main/resources/application.yml

spring:
  application:
    name: service-consumer
  profiles:
    active: dev
  cloud:
    consul:
      # 服务发现配置
      discovery:
        # 启用服务发现
        enabled: true
        # 启用服务注册
        register: true
        # 服务停止时取消注册
        deregister: true
        # 表示注册时使用IP而不是hostname
        prefer-ip-address: true
        # 执行监控检查的频率
        health-check-interval: 30s
        # 设置健康检查失败多长时间后，取消注册
        health-check-critical-timeout: 30s
        # 健康检查的路径
        health-check-path: /actuator/info
        # 服务注册标识，格式为：应用名称+服务器IP+端口
        instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${server.port}
server:
  port: 8001

springcloud-consul/service-consumer/src/main/resources/bootstrap.yml

# bootstrap.yml
# consul 使用动态配置，必须在bootstrap.yml中配置好动态配置项目的配置
spring:
  cloud:
    consul:
      host: localhost
      port: 8500
      #enabled将此值设置为“false”禁用Consul配置
      config:
        enabled: true   #默认是true --
        format: YAML    # 表示consul上面文件的格式 有四种 YAML PROPERTIES KEY-VALUE FILES
        data-key: data   #表示consul上面的KEY值(或者说文件的名字) 默认是data
        # watch选项为配置监视功能，主要监视配置的改变
        watch:
          enabled: true
          delay: 10000
          wait-time: 30

六、测试

由于篇幅有限，测试效果见下一篇文章。

https://blog.csdn.net/forest_long/article/details/129288367