Spring cloud day(4) ribbon和feign

一、ribbon

1.1 ribbon概念

1.2 负载均衡

• 集中式LB

• 进程内LB

1.3 ribbon架构

1.4 ribbom pom

<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-ribbon -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
    <version>2.2.10.RELEASE</version>
</dependency>

1.5 restemplate 中的object和entity

• entity举例

public CommenResult<Payment> getPaymentEntity(@PathVariable("id") int id){
        ResponseEntity<CommenResult> forEntity = restTemplate.getForEntity(PAYMENT_URL + "/getPayment?id=" + id, CommenResult.class);
        if(forEntity.getStatusCode().is2xxSuccessful()){
            return forEntity.getBody();
        }else {
            return  new CommenResult<>(444,"failed");
        }
    }

1.6 IRule

• 根据特定的算法从服务列表中选择一个要访问的服务

1.7 ribbon规则替换

• 步骤
  
• 注意
  替换规则不能与componentscan注解扫描到的在同一个包或者子包中
• 替换配置类

@Configuration
public class ruleConfig {
    @Bean
    public IRule myRule(){
        //定义为随机
        return new RandomRule();
    }
}

• 主启动类添加注解:@RibbonClient
• name：服务名称,configuration :规则配置类

@SpringBootApplication
@EnableEurekaClient
@RibbonClient(name = "payment-services-8002",configuration = ruleConfig.class)
public class OrderBoot {
    public static void main(String[] args) {
        SpringApplication.run(OrderBoot.class, args);
    }
}

二、feign

2.1 概念

2.2 Feign和openFeign

2.3 openFeign的调用步骤

• pom

<dependencies>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>CommModule</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <!-- 引入自己定义的api通用包 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</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>-->
        <!--            <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>

• yml

server:
  port: 80

#spring:
#  application:
#    name: cloud-order-service

eureka:
  client:
    register-with-eureka: false # 不注册进eureka服务中心
    service-url:
      defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/

• 主启动类：@EnableFeignClients

@SpringBootApplication
@EnableFeignClients // 启动feign
public class feignMain {

    public static void main(String[] args) {
        SpringApplication.run(feignMain.class, args);
        System.out.println("启动成功");

    }

}

• 业务类：与远程接口提供的业务对应,@FeignClient

@Component
//微服务名称
@FeignClient(value = "PAYMENT-SERVICE")
public interface PaymentService {
    //服务端的接口
    @GetMapping("/getPayment")
    public CommenResult getPayment(@RequestParam("id")int id);
}

• controller

@RestController
@RequestMapping("consumer")
@Slf4j
public class feignController{
    @Resource
    private PaymentService paymentService;

    @GetMapping(value = "/feign/payment/get/{id}")
    public CommenResult<Payment> getPaymentById(@PathVariable("id") int id) {
        return paymentService.getPayment(id);
    }

}

• 负载均衡
  feign自身集合了

2.4 feign过程图

• feign把远程提供的服务在本地端包装到接口中，自己就可以调用

2.5 feign超市控制

• 测试超时控制，服务端8081业务

    @GetMapping("/payment/timeout")
    public String testTimeOut() throws InterruptedException {
        TimeUnit.SECONDS.sleep(3);
        return serverport;
    }

• 相关yml配置

ribbon:
  #指的是建立连接所用的时间，适用于网络状况正常的情况下, 两端连接所用的时间
  ReadTimeout: 5000
  #指的是建立连接后从服务器读取到可用资源所用的时间
  ConnectTimeout: 5000

2.6 日志增强

• 日志级别
  
• 配置类

@Configuration
public class feignConfig {
    @Bean
    Logger.Level feignLoggerLevel() {
        return Logger.Level.FULL;
    }
}

• 对应yml配置

logging:
  level:
    # feign日志以 debug 级别监控 com.atguigu.springcloud.service.PaymentFeignService 接口
    com.atguigu.springcloud.service.PaymentFeignService: debug

三、 feign案例

3.1 调用方

3.3.1 pom

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

3.3.2 @EnableFeignClients

• 开启feign功能

@SpringBootApplication
@ComponentScan({"com.atguigu.guli"})
@EnableFeignClients
@EnableDiscoveryClient
public class ServiceEduApplication {
    public static void main(String[] args) {
        SpringApplication.run(ServiceEduApplication.class, args);
    }
}

3.3.3 远程接口本地化

• value:目标服务的名称

@Service
@FeignClient(value = "service-cms", fallback = TestFeignFall.class)
public interface TestLogService {
    @GetMapping("/test/log/first")
    public String getSth();
    @PostMapping("/test/log/second")
    public String setSth(String name);
}

• fallback:就是实现代理接口，当远程接口出错或者宕机都会启用里面的方法。

@Service
public class TestFeignFall implements TestLogService {
    @Override
    public String getSth() {
        return "error get";
    }

    @Override
    public String setSth(String name) {
        return "error set";
    }
}

3.2 远程服务提供方