（转）SpringBoot系列—Spring Cloud快速入门

dependencies {compile('org.springframework.boot:spring-boot-starter-web')compile('org.springframework.boot:spring-boot-starter-actuator')compile('org.springframework.cloud:spring-cloud-starter')testCompile('org.springframework.boot:spring-boot-starter-test')
}

以下粘贴每个微服务的关键代码，代码说明都在对应的注释里

1.发现服务 discovery

dependencies {//服务发现依赖于Eureka Servercompile('org.springframework.cloud:spring-cloud-starter-eureka-server')
}

@SpringBootApplication
@EnableEurekaServer //开启对Eureka Server的支持
public class DiscoveryApplication {public static void main(String[] args) {SpringApplication.run(DiscoveryApplication.class, args);}
}

server:
  port: 8761 #当前Eureka Server的服务器端口号
eureka:
  instance:
    hostname: localhost #当前Eureka Server的hostname
client:
    register-with-eureka: false #当前服务不需要注册到Eureka Server
fetch-registry: false

2.配置 config

dependencies {//配置服务依赖compile('org.springframework.cloud:spring-cloud-config-server')//Eureka客户端依赖compile('org.springframework.cloud:spring-cloud-starter-eureka')
}

@SpringBootApplication
@EnableConfigServer//开启配置服务器支持
@EnableEurekaClient//开启Eureka Server的客户端支持
public class ConfigApplication {public static void main(String[] args) {SpringApplication.run(ConfigApplication.class, args);}
}

#Spring Cloud 应用提供使用l 负责从外部资源加载配置熟悉
spring:
  application:
    name: config #在Eureka Server 注册的服务名为config
profiles:
    active: native #配置服务器使用本地配置（默认为git）
eureka:
  instance:
    non-secure-port: ${server.port:8888} #若环境变量中的server.port有值则用，没有用8080
metadata-map:
      instanceId: ${spring.application.name}:${random.value} #配置在Eureka Server中的实例ID
client:
    service-url:
      defaultZone: ${eureka.host:localhost}:${eureka.port:8761}/eureka/ #Eureka客户端设置Eureka Server的地址

#l 配置其他应用所需的配置文件位于类路径下的config目录
#配置文件命名规则：应用名&#l
spring:
  cloud:
    config:
      server:
        native:
          search-locations: classpath:/configserver:
  port: 8888

为person服务提供配置文件

3.服务模块 person

dependencies {// config server 配置依赖compile('org.springframework.cloud:spring-cloud-config-client')// Eureka 客户端依赖compile('org.springframework.cloud:spring-cloud-starter-eureka')
}

@SpringBootApplication
@EnableDiscoveryClient //在这里与@EnableEurekaClient的功能一样
public class PersonApplication {public static void main(String[] args) {SpringApplication.run(PersonApplication.class, args);}
}

@RestController
public class PersonController {@Value("${my.message}")private String message;@RequestMapping(value = "/save", method = RequestMethod.POST)public Person savePerson(@RequestBody String name){Person person = new Person(name);System.out.println(message);return person;}
}

spring:
  application:
    name: personcloud:
      config:
        enabled: truediscovery:
          enabled: trueservice-id: CONFIG #指定Config Server的服务名，通过Eureka Server 发现Config Server。获取l
eureka:
  instance:
    non-secure-port: ${server.port:8082}client:
    service-url:
      defaultZone: ${eureka.host:localhost}:${eureka.port:8761}/eureka/

4.UI模块

dependencies {// config Server 配置依赖compile('org.springframework.cloud:spring-cloud-config-client')// Eureka 客户端依赖compile('org.springframework.cloud:spring-cloud-starter-eureka')// 断路器依赖compile('org.springframework.cloud:spring-cloud-starter-hystrix')// 支持路由网关依赖compile('org.springframework.cloud:spring-cloud-starter-zuul')// feign负责均衡依赖compile('org.springframework.cloud:spring-cloud-starter-feign')// ribbon负责均衡依赖compile('org.springframework.cloud:spring-cloud-starter-ribbon')
}

@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients //开启feign客户端支持
@EnableCircuitBreaker // 开启断路器的支持
@EnableZuulProxy // 开启网关代理支持
public class UiApplication {public static void main(String[] args) {SpringApplication.run(UiApplication.class, args);}
}

@FeignClient("person") //使用person调用person server，person为服务名
public interface PersonService {@RequestMapping(method = RequestMethod.POST, value = "/save",produces = MediaType.APPLICATION_JSON_VALUE, consumes = MediaType.APPLICATION_JSON_VALUE)@ResponseBodyPerson save(@RequestBody String name);
}

@Service
public class PersonHystrixService {@AutowiredPersonService personService;//使用HystrixCommand的fallbackMethod参数指定，当本方法调用失败时调用后路方法fallbackSave@HystrixCommand(fallbackMethod = "fallbackSave")public Person save(String name){return personService.save(name);}public Person fallbackSave(String name){Person person = new Person(name+"person service 异常");return person;}
}

注意：本方法与后来方法的参数要一致，否则程序异常：@HystrixCommand fallback method wasn't found

@RestController
public class PersonController {@AutowiredPersonHystrixService personHystrixService;@RequestMapping(value = "/save",method = RequestMethod.GET)public Person save(){return personHystrixService.save("xianjj");}
}

配置省略

5.断路器监控 monitor

dependencies {//断路器依赖compile('org.springframework.cloud:spring-cloud-starter-hystrix-dashboard')compile('org.springframework.cloud:spring-cloud-starter-turbine')
}

@SpringBootApplication
@EnableEurekaClient
@EnableHystrixDashboard
@EnableTurbine
public class MonitorApplication {public static void main(String[] args) {SpringApplication.run(MonitorApplication.class, args);}
}

配置省略

运行

依次启动discovery，config服务，其余微服务部分顺序启动，最后启动monitor。

1.访问127.0.0.1:8761/，查看发现服务 Eureka Server

2.访问UI服务的controller接口127.0.0.1/save

成功时返回：

关闭person服务，调用接口异常（feign找不到rest服务），执行后备方法

3.断路器监控

访问：127.0.0.1:8989/hystrix.stream

输入：127.0.0.1/hystrix.stream

github源码下载地址：

该项目示例源码下载：

Spring Cloud中文官方网站：/

注意事项：

为方便阅读，在配置文件中添加了相应的注释，若项目启动时报异常：Caused by: org.YAMLException:Java.nio.charset.MalformedInputException: Input length = 1

可以将l文件中的注释内容删掉，再启动；由于YMAL的语法校验比较严格。