SpringCloud之Ribbon-负载均衡-蒲公英云

负载均衡:Spring Cloud Ribbon

Spring Cloud Ribbon 是一个基于Http和TCP的客服端负载均衡工具，它是基于Netflix Ribbon实现的。通过SpringCloud的自动配置使得项目可以自动的给RestTemplate添加拦截器，实现负载均衡的作用。

快速入门

pom.xml

<?xml version=”1.0” encoding=”UTF-8”?>
4.0.0
com.mask
cloud
1.0-SNAPSHOT
UTF-8
1.8

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.5.RELEASE</version>
  </parent>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-dependencies</artifactId>
        <version>Greenwich.SR1</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

application.properties

server.port=8080

server.port=8088
USER-SERVICE.ribbon.listOfServers=localhost:8080,localhost:8088
USER-SERVICE.ribbon.NFLoadBalancerRuleClassName=com.netflix.loadbalancer.RandomRule

UserController

@RestController
@RequestMapping(“manager”)
public class UserController {

@RequestMapping(value="user/{id}",method = { RequestMethod.GET})
public User queyUserById(@PathVariable(value = "id") Integer id){ 
    System.out.println("-------getUser--------");
    return new User("张三", new Date(), true, 12345.00);
}
@RequestMapping(value="user",method = { RequestMethod.POST})
public User saveUser(@RequestBody User user){ 
    System.out.println("-------saveUser--------");
    return user;
}
@RequestMapping(value="user",method = { RequestMethod.PUT})
public void update(@RequestBody User user){ 
    System.out.println("-------updateUser--------");
}
@RequestMapping(value="user/{pageNow}/{pageSize}",method = { RequestMethod.GET})
public List<User> queyUserByPage(@PathVariable(value = "pageNow") Integer pageNow,
                                 @PathVariable(value = "pageSize") Integer pageSize){ 
    List<User> list = new ArrayList<>();
    list.add(new User("张三", new Date(), false, 11111.00));
    list.add(new User("李四", new Date(), true, 20000.00));
    System.out.println("-------getUserPage--------");
    return list;
}
@RequestMapping(value="user/{ids}",method = { RequestMethod.DELETE})
public void deleteUserById(@PathVariable(value = "ids") Integer[] ids){ 
    System.out.println("-------deleteUsers--------");
}

}

SpringRibbonApplication

@SpringBootApplication
public class SpringRibbonApplication {

public static void main(String[] args) { 
    SpringApplication.run(SpringRibbonApplication.class,args);
}
@Bean
@LoadBalanced
public RestTemplate restTemplate(){ 
    return new RestTemplate();
}

}

User

public class User implements Serializable {

private Integer id;
private String name;
@DateTimeFormat(pattern = "yyyy-MM-dd HHss")
@JsonFormat(pattern = "yyyy-MM-dd HHss")
private Date birthDay;
private Boolean sex;
private Double salary;

}

RestTemplateTests

@SpringBootTest(classes = SpringRibbonApplication.class)
@RunWith(SpringRunner.class)
public class RestTemplateTests {

@Autowired
private RestTemplate restTemplate;
@Test
public void testQueryUserById(){ 
    String url="http://USER-SERVICE/manager/user/1";
    User user = restTemplate.getForObject(url, User.class);
    System.out.println(user);
}
@Test
public void testQueryUserByPage(){ 
    String url="http://USER-SERVICE/manager/user/1/10";
    List<User> users = restTemplate.getForObject(url, List.class);
    for (int i = 0; i < users.size(); i++) { 
        System.out.println(users.get(i));
    }
}
@Test
public void testSaveUser(){ 
    String url="http://USER-SERVICE/manager/user";
    User user = restTemplate.postForObject(url, new User("李四", new Date(), true, 15000.0), User.class);
    System.out.println(user);
}
@Test
public void testUpdateUser(){ 
    String url="http://USER-SERVICE/manager/user";
    User user = new User("李四", new Date(), true, 18000.0);
    user.setId(3);
    restTemplate.put(url,user);
}
@Test
public void testDeleteUser(){ 
    String url="http://USER-SERVICE/manager/user/1,2,3";
    restTemplate.delete(url);
}

}

除此自外，SpringCloud提供了一种基于配置文件的配置方式

SpringRibbonApplication

@SpringBootApplication
@RibbonClient(name = “USER-SERVICE”,configuration = { UserSerivceRibbonConfigure.class})
public class SpringRibbonApplication {

public static void main(String[] args) { 
    SpringApplication.run(SpringRibbonApplication.class,args);
}
@Bean
@LoadBalanced
public RestTemplate restTemplate(){ 
    return new RestTemplate();
}

}

UserSerivceRibbonConfigure

@Configuration
public class UserSerivceRibbonConfigure {

@Bean
public ServerList<Server> ribbonServerList(){ 
    Server server1 = new Server("localhost", 8080);
    server1.setZone("beijing");
    Server server2 = new Server("localhost", 9090);
    server2.setZone("shanghai");
    return new StaticServerList<Server>(server1,server2);
}
@Bean
public IRule ribbonRule(){ 
    return new RandomRule();
}
@Bean
public ZonePreferenceServerListFilter ribbonServerListFilter(){ 
    ZonePreferenceServerListFilter filter = new ZonePreferenceServerListFilter();
    filter.setZone("beijing");
    return filter;
}

}

用户可以直接使用LoadBalancerClient查询服务列表

@Autowired
private LoadBalancerClient loadBalancer;
@Test
public void testChoose(){ 
  for (Integer i=0;i<10;i++){ 
    ServiceInstance instance = loadBalancer.choose("stores");
    URI storesUri = URI.create(String.format("http://%s:%s", instance.getHost(), instance.getPort()));
    System.out.println(storesUri);
  }
}