Zuul實(shí)現(xiàn)服務(wù)網(wǎng)關(guān)路由全過程

更新時(shí)間：2025年07月17日 09:58:21 作者：小凱 ?

文章介紹了微服務(wù)架構(gòu)中路由層的作用,Spring Cloud Zuul作為Netflix的動(dòng)態(tài)路由和負(fù)載均衡器,雖有Zuul 2,但Spring Cloud Gateway已成為更推薦的網(wǎng)關(guān)方案,強(qiáng)調(diào)路由層的高可用性對(duì)系統(tǒng)穩(wěn)定性至關(guān)重要

前言

為什么會(huì)有路由層？

因?yàn)樵谖⒎?wù)架構(gòu)設(shè)計(jì)中，往往并不會(huì)直接將服務(wù)暴漏給調(diào)用端，而是通過調(diào)用路由層進(jìn)行業(yè)務(wù)隔離，以達(dá)到不同的業(yè)務(wù)調(diào)用對(duì)應(yīng)的服務(wù)模塊。

Spring Cloud Zuul

Spring Cloud Zuul 路由是微服務(wù)架構(gòu)的不可或缺的一部分，提供動(dòng)態(tài)路由、監(jiān)控、彈性、安全等的邊緣服務(wù)。

Zuul 是 Netflix 出品的一個(gè)基于 JVM 路由和服務(wù)端的負(fù)載均衡器。

環(huán)境準(zhǔn)備

1.jdk 1.8、idea2018、Maven3

2.Spring Boot 2.0.6.RELEASE

3.Spring Cloud Finchley.SR2

代碼示例

itstack-demo-springcloud-08
├── itstack-demo-springcloud-eureka-client
│   └── src
│       └── main
│           ├── java
│           │   └── org.itstack.demo
│           │        ├── web
│           │        │   └── EurekaClientController.java
│           │        └── EurekaClientApplication.java
│           └── resources   
│               └── application.yml
├── itstack-demo-springcloud-eureka-server
│   └── src
│       └── main
│           ├── java
│           │   └── org.itstack.demo
│           │        └── EurekaServerApplication.java
│           └── resources   
│               └── application.yml
├── itstack-demo-springcloud-hystrix-feign
│   └── src
│       └── main
│           ├── java
│           │   └── org.itstack.demo
│           │        ├── service
│           │        │   ├── hystrix
│           │        │   │   └── FeignServiceHystrix.java
│           │        │   └── FeignService.java
│           │        ├── web
│           │        │   └── FeignController.java
│           │        └── FeignApplication.java
│           └── resources   
│               └── application.yml
├── itstack-demo-springcloud-hystrix-ribbon
│   └── src
│       └── main
│           ├── java
│           │   └── org.itstack.demo
│           │        ├── service
│           │        │   └── RibbonService.java
│           │        ├── web
│           │        │   └── RibbonController.java      
│           │        └── RibbonApplication.java
│           └── resources   
│               └── application.yml
└── itstack-demo-springcloud-zuul
    └── src
        └── main
            ├── java
            │   └── org.itstack.demo   
            │        └── ZuulApplication.java
            └── resources   
                └── application.yml

itstack-demo-springcloud-eureka-client | 服務(wù)提供方

提供一個(gè)查詢用戶信息的簡(jiǎn)單方法，在配置文件中通過修改端口啟動(dòng)2次，模擬雙實(shí)例應(yīng)用，為調(diào)用方負(fù)載做準(zhǔn)備。

web/EurekaClientController.java & 注意@EnableEurekaClient用于向注冊(cè)中心提供服務(wù)

@EnableEurekaClient
@RestController
public class EurekaClientController {

    @Value("${server.port}")
    private int port;

    @RequestMapping(path = "/api/queryUserInfo", method = RequestMethod.GET)
    public String queryUserInfo(@RequestParam String userId) {
        return "Hi 微信公眾號(hào)：bugstack蟲洞棧 | " + userId + " >: from eureka client port: " + port;
    }

}

EurekaClientApplication.java & 服務(wù)啟動(dòng)類

@SpringBootApplication
public class EurekaClientApplication {

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

}

pom.xml & 配置文件指向注冊(cè)中心

server:
  port: 8001

spring:
  application:
    name: itstack-demo-springcloud-eureka-client

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:7397/eureka/

itstack-demo-springcloud-eureka-server | 單個(gè)服務(wù)注冊(cè)中心

服務(wù)注冊(cè)中心用于承載接口提供方向上注冊(cè)，同時(shí)正在調(diào)用方鏈接后可以獲取指定應(yīng)用的服務(wù)實(shí)例。

EurekaServerApplication.java & 通過注解@EnableEurekaServer啟動(dòng)服務(wù)注冊(cè)與發(fā)現(xiàn)中心

@SpringBootApplication
@EnableEurekaServer
public class EurekaServerApplication {

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

}

pom.xml & 服務(wù)注冊(cè)中心

server:
  port: 7397

eureka:
  instance:
    hostname: localhost
  client:
    registerWithEureka: false
    fetchRegistry: false
    serviceUrl:
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

spring:
  application:
    name: itstack-demo-springcloud-eureka-server

itstack-demo-springcloud-feign | Feign服務(wù)調(diào)用方

Feign 是一個(gè)聲明式的 Web Service 客戶端，它的目的就是讓 Web Service 調(diào)用更加簡(jiǎn)單。它整合了 Ribbon 和 Hystrix，從而讓我們不再需要顯式地使用這兩個(gè)組件。Feign 還提供了 HTTP 請(qǐng)求的模板，通過編寫簡(jiǎn)單的接口和插入注解，我們就可以定義好 HTTP 請(qǐng)求的參數(shù)、格式、地址等信息。接下來，F(xiàn)eign 會(huì)完全代理 HTTP 的請(qǐng)求，我們只需要像調(diào)用方法一樣調(diào)用它就可以完成服務(wù)請(qǐng)求。

Feign 具有如下特性：

可插拔的注解支持，包括 Feign 注解和 JAX-RS 注解支持可插拔的 HTTP 編碼器和解碼器支持 Hystrix 和它的 Fallback 支持 Ribbon 的負(fù)載均衡支持 HTTP 請(qǐng)求和響應(yīng)的壓縮

service/FeignService.java |

注解方式調(diào)用，方便易用。@FeignClient會(huì)在調(diào)用時(shí)進(jìn)行解析服務(wù)到具體的http://ip:port/

@FeignClient(value = "itstack-demo-springcloud-eureka-client", fallback = FeignServiceHystrix.class)
public interface FeignService {

    @RequestMapping(value = "/api/queryUserInfo", method = RequestMethod.GET)
    String queryUserInfo(@RequestParam String userId);

}

service/hystrix/FeignServiceHystrix.java | 提供熔斷服務(wù)，當(dāng)發(fā)生異常時(shí)主動(dòng)返回預(yù)定結(jié)果

@Component
public class FeignServiceHystrix implements FeignService {

    @Override
    public String queryUserInfo(String userId) {
        return "queryUserInfo by userId：" + userId + " err！from feign hystrix";
    }
    
}

web/FeignController.java | 使用接口提供服務(wù) From Feign

@RestController
public class FeignController {

    @Resource
    private FeignService ribbonService;

    @RequestMapping(path = "/api/queryUserInfo", method = RequestMethod.GET)
    public String queryUserInfo(@RequestParam String userId) {
        return ribbonService.queryUserInfo(userId) + " From Feign";
    }

}

FeignApplication.java |

注解@EnableEurekaClient、@EnableFeignClients、@EnableDiscoveryClient獲取調(diào)用注冊(cè)中心服務(wù)

@SpringBootApplication
@EnableEurekaClient
@EnableDiscoveryClient
@EnableFeignClients
@EnableHystrix
public class FeignApplication {

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

}

application.yml | eureka服務(wù)配置，從注冊(cè)中心獲取可用服務(wù)。開啟hystrix=true

server:
  port: 9001

spring:
  application:
    name: itstack-demo-springcloud-feign

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:7397/eureka/

feign.hystrix.enabled: true

itstack-demo-springcloud-ribbon | Ribbon服務(wù)調(diào)用方

Ribbon是一個(gè)基于 HTTP 和 TCP 的客戶端負(fù)載均衡器。它可以通過在客戶端中配置 ribbonServerList 來設(shè)置服務(wù)端列表去輪詢?cè)L問以達(dá)到均衡負(fù)載的作用。

當(dāng) Ribbon 與 Eureka 聯(lián)合使用時(shí)，ribbonServerList 會(huì)被 DiscoveryEnabledNIWSServerList 重寫，擴(kuò)展成從 Eureka 注冊(cè)中心中獲取服務(wù)實(shí)例列表。同時(shí)它也會(huì)用 NIWSDiscoveryPing 來取代 IPing，它將職責(zé)委托給 Eureka 來確定服務(wù)端是否已經(jīng)啟動(dòng)。

service/RibbonService.java |

接口式硬編碼調(diào)用不太易于維護(hù)，因此也是比較少用的方式。hystrix實(shí)際通過getFallback()返回熔斷結(jié)果

@Service
public class RibbonService {

    @Autowired
    private RestTemplate restTemplate;

    @HystrixCommand(fallbackMethod = "queryUserInfoFallback")
    public String queryUserInfo(String userId) {
        return restTemplate.getForObject("http://ITSTACK-DEMO-SPRINGCLOUD-EUREKA-CLIENT/api/queryUserInfo?userId=" + userId, String.class);
    }

    /**
     * Specifies a method to process fallback logic.
     * A fallback method should be defined in the same class where is HystrixCommand.
     * Also a fallback method should have same signature to a method which was invoked as hystrix command.
     * for example:
     * <code>
     *      @HystrixCommand(fallbackMethod = "getByIdFallback")
     *      public String getById(String id) {...}
     *
     *      private String getByIdFallback(String id) {...}
     * </code>
     * Also a fallback method can be annotated with {@link HystrixCommand}
     * <p/>
     * default => see {@link com.netflix.hystrix.contrib.javanica.command.GenericCommand#getFallback()}
     *
     * @return method name
     *
     * getFallback()
     * 
     * @Override
     * protected Object getFallback() {
     *     final CommandAction commandAction = getFallbackAction();
     *     if (commandAction != null) {
     *         try {
     *             return process(new Action() {
     *                 @Override
     *                 Object execute() {
     *                     MetaHolder metaHolder = commandAction.getMetaHolder();
     *                     Object[] args = createArgsForFallback(metaHolder, getExecutionException());
     *                     return commandAction.executeWithArgs(metaHolder.getFallbackExecutionType(), args);
     *                 }
     *             });
     *         } catch (Throwable e) {
     *             LOGGER.error(FallbackErrorMessageBuilder.create()
     *                     .append(commandAction, e).build());
     *             throw new FallbackInvocationException(unwrapCause(e));
     *         }
     *     } else {
     *         return super.getFallback();
     *     }
     * }
     */
    public String queryUserInfoFallback(String userId) {
        return "queryUserInfo by userId：" + userId + " err！from ribbon hystrix";
    }

}

web/RibbonController.java | 使用接口提供服務(wù) From Ribbon

@RestController
public class RibbonController {

    @Resource
    private RibbonService ribbonService;

    @RequestMapping(path = "/api/queryUserInfo", method = RequestMethod.GET)
    public String queryUserInfo(@RequestParam String userId) {
        return ribbonService.queryUserInfo(userId) + " From Ribbon";
    }
    
}

RibbonApplication.java |

通過注解@LoadBalanced注冊(cè)rest模版，用于Ribbon接口調(diào)用。并啟動(dòng)@EnableHystrix

@SpringBootApplication
@EnableEurekaClient
@EnableDiscoveryClient
@EnableHystrix
public class RibbonApplication {

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

    @Bean
    @LoadBalanced
    RestTemplate restTemplate() {
        return new RestTemplate();
    }

}

application.yml | eureka服務(wù)配置，從注冊(cè)中心獲取可用服務(wù)

server:
  port: 9002

spring:
  application:
    name: itstack-demo-springcloud-ribbon

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:7397/eureka/

itstack-demo-springcloud-zuul | Zull路由層

Spring Cloud Zuul 路由是微服務(wù)架構(gòu)的不可或缺的一部分，提供動(dòng)態(tài)路由、監(jiān)控、彈性、安全等的邊緣服務(wù)。Zuul 是 Netflix 出品的一個(gè)基于 JVM 路由和服務(wù)端的負(fù)載均衡器。

ZuulApplication.java & 路由服務(wù)啟動(dòng)

@SpringBootApplication
@EnableZuulProxy
@EnableEurekaClient
@EnableDiscoveryClient
public class ZuulApplication {

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

}

pom.mxl & 路由配置

server:
  port: 10001

spring:
  application:
    name: itstack-demo-ddd-zuul

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:7397/eureka/

# http://localhost:10001/route-a/api/queryUserInfo?userId=111
# http://localhost:10001/route-b/api/queryUserInfo?userId=111
zuul:
  routes:
    api-a:
      path: /route-a/**
      serviceId: itstack-demo-springcloud-feign
    api-b:
      path: /route-b/**
      serviceId: itstack-demo-springcloud-ribbon

測(cè)試驗(yàn)證

1.分別啟動(dòng)如下系統(tǒng)模擬

itstack-demo-springcloud-eureka-server 服務(wù)注冊(cè)發(fā)現(xiàn)中心
itstack-demo-springcloud-eureka-client 測(cè)試接口提供方
itstack-demo-springcloud-hystrix-feign 接口調(diào)用方Feign
itstack-demo-springcloud-hystrix-ribbon 接口調(diào)用方Ribbon
itstack-demo-springcloud-zuul 路由服務(wù)

2.測(cè)試接口

訪問Feign、Ribbon接口，驗(yàn)證服務(wù)是否可用；http://localhost:9001/api/queryUserInfo?userId=111、http://localhost:9002/api/queryUserInfo?userId=111
訪問路由接口A；http://localhost:10001/route-a/api/queryUserInfo?userId=111
訪問路由接口B；http://localhost:10001/route-b/api/queryUserInfo?userId=111