<!--公共的一些配置-->
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>
   <!--SpringBoot-->
    <parent>
        <groupId> org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.5.RELEASE</version>
    </parent>
    <!--SpringCloud-->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2.2.1.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Hoxton.SR3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--導入lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
    </dependencies>

 <dependency>
     <groupId>com.alibaba.cloud </groupId>
     <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

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

server:
  port: 20010
spring:
  application:
    name: Order-server
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

<dependency>
     <groupId>com.alibaba.cloud </groupId>
     <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

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

server:
  port: 30010
spring:
  application:
    name: Order-client
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

<dependencies>
 <!--        配置中心客戶端-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
        <!-- 服務注冊與發(fā)現(xiàn)-->
        <dependency>
            <groupId>com.alibaba.cloud </groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>springcloudalibaba-user-common</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>

@RefreshScope  //刷新配置
@RestController
public class UserController {
    @Value("${temp.notify}")
    private String notify;
    @GetMapping("/user/{id}")
    public User getById(@PathVariable Long id){
        User user = new User(id,"root"+notify ,null);
        return user;
    }
}

server:
  port: 30010
spring:
  application:
    name: Order-client
  profiles:
    active: dev
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
      config:
        server-addr: 127.0.0.1:8848
        file-extension: yaml
        prefix: application-user
        group: DEFAULT_GROUP

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>

spring:
  cloud:
    sentinel:
      transport:
        dashboard: localhost:1111

 @SentinelResource(value = "getUser",blockHandler = "LimitResource")

@RefreshScope
@RestController
@RequestMapping("/user")
public class UserController {
    @Value("${temp.notify}")
    private String notify;
    @Autowired
    private OrderOpenFeignClient feignClient;
    //限制的資源
    @SentinelResource(value = "getUser",blockHandler = "LimitResource")
//    給資源取名user，后續(xù)通過名字來進行限流
    @GetMapping("/{id}")
    public User getUser(@PathVariable("id") Long id){
        //發(fā)起遠程調用
        List<Order> orders =feignClient.getList(id);
        int i=new Random().nextInt(2);
        System.out.println(1/i);
        User user = new User(id,"root"+notify ,orders);
        return user;
    }
       public User LimitResource(@PathVariable("id") Long id,BlockException e){
           e.printStackTrace();
             return new User(-1L,"限流了",null);
   }
}

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

feign:
  sentinel:
    enabled: true #熔斷

@FeignClient(value = "Order-server")
public interface OrderOpenFeignClient {
    @GetMapping("/order/{id}")
    public List<Order> getList(@PathVariable("id") Long id);
}

@Component
public class UserFallBack implements FallbackFactory<OrderOpenFeignClient> {
   @Override
   public OrderOpenFeignClient create(Throwable throwable) {
       return id ->Arrays.asList(new Order(-2L,"服務暫時不可用","請您稍后再試"));
    }
}

@RefreshScope
@RestController
@RequestMapping("/user")
public class UserController {
    @Value("${temp.notify}")
    private String notify;
    @Autowired
    private OrderOpenFeignClient feignClient;
    //限制的資源
    @SentinelResource(value = "getUser",blockHandler = "LimitResource",blockHandlerClass = UserFallback.class,
    fallback = "Error")
//    給資源取名user，后續(xù)通過名字來進行限流
    @GetMapping("/{id}")
    public User getUser(@PathVariable("id") Long id){
        //發(fā)起遠程調用
        List<Order> orders =feignClient.getList(id);
        int i=new Random().nextInt(2);
        System.out.println(1/i);
        User user = new User(id,"root"+notify ,orders);
        return user;
    }
    //方案1
//    public User LimitResource(@PathVariable("id") Long id,BlockException e){
//        e.printStackTrace();
//        return new User(-1L,"限流了",null);
//    }
    public User Error(@PathVariable("id") Long id){
        return new User(-1L,"熔斷數(shù)據(jù)集",null);
    }
}