Spring Cloud Alibaba

概述

Spring Cloud Alibaba是阿里巴巴开源的微服务解决方案，为Spring Cloud生态提供了一套完整的微服务开发工具。它包含了服务发现、配置管理、消息队列、分布式事务等组件，特别适合在阿里云环境中使用。

核心组件

Nacos - 服务发现与配置管理

服务发现

java

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

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

yaml

spring:
  application:
    name: service-provider
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848

spring:
  application:
    name: service-provider
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848

配置管理

yaml

spring:
  application:
    name: service-provider
  cloud:
    nacos:
      config:
        server-addr: localhost:8848
        file-extension: yaml
        group: DEFAULT_GROUP

spring:
  application:
    name: service-provider
  cloud:
    nacos:
      config:
        server-addr: localhost:8848
        file-extension: yaml
        group: DEFAULT_GROUP

java

@RestController
@RefreshScope
public class ConfigController {
    
    @Value("${user.name:unknown}")
    private String userName;
    
    @GetMapping("/config")
    public String getConfig() {
        return "User name: " + userName;
    }
}

@RestController
@RefreshScope
public class ConfigController {
    
    @Value("${user.name:unknown}")
    private String userName;
    
    @GetMapping("/config")
    public String getConfig() {
        return "User name: " + userName;
    }
}

Sentinel - 流量控制与熔断降级

基本使用

xml

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

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

java

@RestController
public class TestController {
    
    @GetMapping("/hello")
    @SentinelResource(value = "hello", fallback = "helloFallback")
    public String hello() {
        return "Hello Sentinel";
    }
    
    public String helloFallback() {
        return "Hello Fallback";
    }
}

@RestController
public class TestController {
    
    @GetMapping("/hello")
    @SentinelResource(value = "hello", fallback = "helloFallback")
    public String hello() {
        return "Hello Sentinel";
    }
    
    public String helloFallback() {
        return "Hello Fallback";
    }
}

流控规则配置

java

@PostConstruct
public void initFlowRules() {
    List<FlowRule> rules = new ArrayList<>();
    FlowRule rule = new FlowRule();
    rule.setResource("hello");
    rule.setGrade(RuleConstant.FLOW_GRADE_QPS);
    rule.setCount(20);
    rules.add(rule);
    FlowRuleManager.loadRules(rules);
}

@PostConstruct
public void initFlowRules() {
    List<FlowRule> rules = new ArrayList<>();
    FlowRule rule = new FlowRule();
    rule.setResource("hello");
    rule.setGrade(RuleConstant.FLOW_GRADE_QPS);
    rule.setCount(20);
    rules.add(rule);
    FlowRuleManager.loadRules(rules);
}

RocketMQ - 消息队列

xml

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

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

消息生产者

java

@Component
public class MessageProducer {
    
    @Autowired
    private RocketMQTemplate rocketMQTemplate;
    
    public void sendMessage(String topic, Object message) {
        rocketMQTemplate.convertAndSend(topic, message);
    }
}

@Component
public class MessageProducer {
    
    @Autowired
    private RocketMQTemplate rocketMQTemplate;
    
    public void sendMessage(String topic, Object message) {
        rocketMQTemplate.convertAndSend(topic, message);
    }
}

消息消费者

java

@Component
@RocketMQMessageListener(topic = "test-topic", consumerGroup = "test-group")
public class MessageConsumer implements RocketMQListener<String> {
    
    @Override
    public void onMessage(String message) {
        System.out.println("Received message: " + message);
    }
}

@Component
@RocketMQMessageListener(topic = "test-topic", consumerGroup = "test-group")
public class MessageConsumer implements RocketMQListener<String> {
    
    @Override
    public void onMessage(String message) {
        System.out.println("Received message: " + message);
    }
}

Seata - 分布式事务

xml

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

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

java

@Service
public class BusinessService {
    
    @Autowired
    private StorageService storageService;
    
    @Autowired
    private OrderService orderService;
    
    @GlobalTransactional
    public void purchase(String userId, String commodityCode, int orderCount) {
        storageService.deduct(commodityCode, orderCount);
        orderService.create(userId, commodityCode, orderCount);
    }
}

@Service
public class BusinessService {
    
    @Autowired
    private StorageService storageService;
    
    @Autowired
    private OrderService orderService;
    
    @GlobalTransactional
    public void purchase(String userId, String commodityCode, int orderCount) {
        storageService.deduct(commodityCode, orderCount);
        orderService.create(userId, commodityCode, orderCount);
    }
}

与Spring Cloud对比

功能	Spring Cloud	Spring Cloud Alibaba
服务发现	Eureka, Consul	Nacos
配置管理	Config Server	Nacos Config
负载均衡	Ribbon, LoadBalancer	Ribbon, LoadBalancer
熔断降级	Hystrix, Resilience4j	Sentinel
网关	Gateway, Zuul	Gateway
消息队列	-	RocketMQ
分布式事务	-	Seata

部署架构

单机部署

bash

# 启动Nacos
sh startup.sh -m standalone

# 启动Sentinel Dashboard
java -jar sentinel-dashboard.jar

# 启动Seata Server
sh seata-server.sh

# 启动Nacos
sh startup.sh -m standalone

# 启动Sentinel Dashboard
java -jar sentinel-dashboard.jar

# 启动Seata Server
sh seata-server.sh

集群部署

yaml

# Nacos集群配置
spring:
  cloud:
    nacos:
      discovery:
        server-addr: nacos1:8848,nacos2:8848,nacos3:8848

# Nacos集群配置
spring:
  cloud:
    nacos:
      discovery:
        server-addr: nacos1:8848,nacos2:8848,nacos3:8848

最佳实践

服务拆分：合理设计服务边界
配置管理：使用Nacos统一管理配置
流量控制：通过Sentinel保护系统稳定性
消息解耦：使用RocketMQ实现服务间异步通信
事务管理：合理使用Seata处理分布式事务
监控告警：集成监控系统，及时发现问题

总结

Spring Cloud Alibaba提供了完整的微服务解决方案，特别适合在阿里云环境中使用。它的组件相比Netflix组件更加活跃，功能也更加丰富，是构建微服务架构的优秀选择。