一个简单的微服务系统：服务注册和发现，服务消费，负载均衡，断路器，智能路由，配置管理
服务注册中心：
eureka是一个高可用组件，没有后端缓存，每一个实例注册后向注册中心发送心跳，默认情况下，erureka server也是一个eureka clinet,必须指定server
引入依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka-server</artifactId>
</dependency>
启用注册中心：
@EnableEurekaServer
@SpringBootApplication
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
YML配置：
server:
port: 8761 spring:
application:
name: microservice-registry
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
registerWithEureka: false
fetchRegistry: false
#serverUrl:
# defaultZone: http://otherRegistry:port/eureka/
eureka客户端：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
启动：
@SpringBootApplication
@EnableDiscoveryClient
@RestController
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
} @RequestMapping("/hi")
public String home(@RequestParam String name) {
return "hi "+name+",i am from port: " +port;
}
}
YML配置：
spring:
application:
name: microservice-producer
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
在微服务架构中，业务都会被拆分成一个独立的服务，服务与服务间基于http restful
springcloud有两种服务调用方式：ribbon+restTemplate和feign，ribbon是一个负载均衡客户端，可以很好控制http和tcp的一些行为，feign默认集成也ribbon
ribbon+restTemplate：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-ribbon</artifactId>
</dependency>
启动：
@SpringBootApplication
@EnableDiscoveryClient
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
} @Bean
@LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
}
调用：
@Service
public class HelloService { @Autowired
RestTemplate restTemplate; public String hiService(String name) {
return restTemplate.getForObject("http://eureka-producer/hi?name="+name,String.class);
} }
YML配置：
spring:
application:
name: microservice-ribbon-consumer
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
feign：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
</dependency>
启动：
@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
调用：
@RestController
public class HiController { @Autowired
SchedualServiceHi schedualServiceHi;
@RequestMapping(value = "/hi",method = RequestMethod.GET)
public String sayHi(@RequestParam String name){
return schedualServiceHi.sayHiFromClientOne(name);
}
} @FeignClient(value = "eureka-producer")
public interface SchedualServiceHi {
@RequestMapping(value = "/hi",method = RequestMethod.GET)
String sayHiFromClientOne(@RequestParam(value = "name") String name);
}
yml配置：
spring:
application:
name: microservice-feign-consumer
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
断路器：应付故障传播问题
ribbon+restTemplate：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-hystrix</artifactId>
</dependency>
启动：
@SpringBootApplication
@EnableDiscoveryClient
@EnableHystrix
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
} @Bean
@LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
}
使用：
@Service
public class HelloService { @Autowired
RestTemplate restTemplate; @HystrixCommand(fallbackMethod = "hiError")
public String hiService(String name) {
return restTemplate.getForObject("http://eureka-producer/hi?name="+name,String.class);
} public String hiError(String name) {
return "hi,"+name+",sorry,error!";
} }
YML中不需要额外配置
feign：
依赖同上
启动：
@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@EnableCircuitBreaker
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
使用：
@FeignClient(value = "eureka-producer", fallback = SchedualServiceHiHystric.class)
public interface SchedualServiceHi {
@RequestMapping(value = "/hi",method = RequestMethod.GET)
String sayHiFromClientOne(@RequestParam(value = "name") String name);
} @Component
public class SchedualServiceHiHystric implements SchedualServiceHi {
@Override
public String sayHiFromClientOne(String name) {
return "sorry "+name;
}
}
yml配置：
额外添加：
feign:
hystrix:
enabled:true
路由网关：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zuul</artifactId>
</dependency>
启动：
@EnableZuulProxy
@EnableDiscoveryClient
@SpringBootApplication
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
yml配置：
spring:
application:
name: microservice-gateway
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/ zuul:
routes:
microservice-producer:
path: /produce/**
serviceId: microservice-producer
配置管理：
服务器依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-config-server</artifactId>
</dependency>
客户端依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
服务器端启动：
@EnableDiscoveryClient
@SpringBootApplication
@EnableConfigServer
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
客户端启动不需要额外添加
服务器端yml配置：
server:
port: 8000 spring:
application:
name: microservice-config
cloud:
config:
server:
native:
search-locations: classpath:/repo
profiles:
active: native eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
客户端yml配置：
spring:
application:
name: microservice-gateway
cloud:
config:
uri: http://localhost:8000
fail-fast: true
profiles:
active: native eureka:
instance:
prefer-ip-address: true
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
监控管理：
依赖：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-turbine</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-netflix-turbine</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-hystrix-dashboard</artifactId>
</dependency>
启动：
@SpringBootApplication
@EnableTurbine
@EnableDiscoveryClient
@EnableHystrixDashboard
public class App
{
public static void main( String[] args )
{
SpringApplication.run(App.class, args);
}
}
yml配置：
server:
port: 8770 security.basic.enabled: false turbine:
aggregator:
clusterConfig: default # 指定聚合哪些集群，多个使用","分割，默认为default。可使用http://.../turbine.stream?cluster={clusterConfig之一}访问
appConfig: microservice-feign-consumer,microservice-ribbon-consumer ### 配置Eureka中的serviceId列表，表明监控哪些服务
clusterNameExpression: new String("default")
# 1. clusterNameExpression指定集群名称，默认表达式appName；此时：turbine.aggregator.clusterConfig需要配置想要监控的应用名称
# 2. 当clusterNameExpression: default时，turbine.aggregator.clusterConfig可以不写，因为默认就是default
# 3. 当clusterNameExpression: metadata['cluster']时，假设想要监控的应用配置了eureka.instance.metadata-map.cluster: ABC，则需要配置，同时turbine.aggregator.clusterConfig: ABC
消息总线：将分布式节点用轻量的消息代理连接起来，可用于广播配置文件的更改或者服务之间的通讯，也可用于监控