Spring Boot集成最佳实践
Spring Boot Starter快速集成 添加依赖 <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId> <version>2022.0.0.0</version> </dependency> 配置文件 spring: application: name: order-service cloud: sentinel: transport: dashboard: localhost:8080 port: 8719 eager: true # 启动时立即初始化 # Web限流 filter: enabled: true url-patterns: /** # 数据源配置 datasource: flow: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-flow-rules groupId: SENTINEL_GROUP rule-type: flow @SentinelResource注解使用 基础用法 @Service public class OrderService { @SentinelResource( value = "createOrder", blockHandler = "handleBlock", fallback = "handleFallback" ) public Order createOrder(OrderDTO dto) { return orderDao.save(dto); } // 限流/熔断处理 public Order handleBlock(OrderDTO dto, BlockException ex) { throw new BusinessException("系统繁忙，请稍后重试"); } // 业务异常处理 public Order handleFallback(OrderDTO dto, Throwable ex) { log.error("创建订单失败", ex); throw new BusinessException("订单创建失败"); } } 异常类分离 public class OrderBlockHandler { public static Order handleBlock(OrderDTO dto, BlockException ex) { return Order.builder().status("BLOCKED").build(); } } public class OrderFallback { public static Order handleFallback(OrderDTO dto, Throwable ex) { return Order.builder().status("FALLBACK").build(); } } @Service public class OrderService { @SentinelResource( value = "createOrder", blockHandlerClass = OrderBlockHandler.class, blockHandler = "handleBlock", fallbackClass = OrderFallback.class, fallback = "handleFallback" ) public Order createOrder(OrderDTO dto) { return orderDao.save(dto); } } RestTemplate集成 @Configuration public class RestTemplateConfig { @Bean @SentinelRestTemplate( blockHandler = "handleBlock", blockHandlerClass = RestTemplateBlockHandler.class, fallback = "handleFallback", fallbackClass = RestTemplateFallback.class ) public RestTemplate restTemplate() { return new RestTemplate(); } } Feign集成 添加依赖 <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> 配置 feign: sentinel: enabled: true 使用 @FeignClient(name = "product-service", fallback = ProductServiceFallback.class) public interface ProductService { @GetMapping("/product/{id}") Product getProduct(@PathVariable Long id); } @Component public class ProductServiceFallback implements ProductService { @Override public Product getProduct(Long id) { return Product.builder() .id(id) .name("商品服务暂时不可用") .build(); } } 全局异常处理 @RestControllerAdvice public class SentinelExceptionHandler { @ExceptionHandler(FlowException.class) public Result handleFlowException(FlowException e) { return Result.error(429, "请求过于频繁"); } @ExceptionHandler(DegradeException.class) public Result handleDegradeException(DegradeException e) { return Result.error(503, "服务降级"); } @ExceptionHandler(BlockException.class) public Result handleBlockException(BlockException e) { return Result.error(500, "系统保护"); } } 规则初始化 @Configuration public class SentinelRuleConfig { @PostConstruct public void initRules() { initFlowRules(); initDegradeRules(); initSystemRules(); } private void initFlowRules() { List<FlowRule> rules = new ArrayList<>(); FlowRule rule = new FlowRule(); rule.setResource("createOrder"); rule.setGrade(RuleConstant.FLOW_GRADE_QPS); rule.setCount(100); rules.add(rule); FlowRuleManager.loadRules(rules); } private void initDegradeRules() { List<DegradeRule> rules = new ArrayList<>(); DegradeRule rule = new DegradeRule(); rule.setResource("callProductService"); rule.setGrade(RuleConstant.DEGRADE_GRADE_RT); rule.setCount(1000); rule.setSlowRatioThreshold(0.5); rules.add(rule); DegradeRuleManager.loadRules(rules); } private void initSystemRules() { List<SystemRule> rules = new ArrayList<>(); SystemRule rule = new SystemRule(); rule.setHighestCpuUsage(0.8); rules.add(rule); SystemRuleManager.loadRules(rules); } } 完整实战案例 @SpringBootApplication @EnableFeignClients public class OrderServiceApplication { public static void main(String[] args) { SpringApplication.run(OrderServiceApplication.class, args); } } @RestController @RequestMapping("/order") public class OrderController { @Autowired private OrderService orderService; @PostMapping("/create") @SentinelResource(value = "orderCreate", blockHandler = "handleBlock") public Result createOrder(@RequestBody OrderDTO dto) { Order order = orderService.createOrder(dto); return Result.success(order); } public Result handleBlock(OrderDTO dto, BlockException ex) { return Result.error(429, "订单创建繁忙，请稍后重试"); } } @Service public class OrderService { @Autowired private ProductService productService; @SentinelResource(value = "createOrderService", fallback = "handleFallback") public Order createOrder(OrderDTO dto) { // 调用商品服务 Product product = productService.getProduct(dto.getProductId()); // 创建订单 Order order = new Order(); order.setProductId(product.getId()); order.setUserId(dto.getUserId()); return orderDao.save(order); } public Order handleFallback(OrderDTO dto, Throwable ex) { log.error("订单创建失败", ex); throw new BusinessException("订单创建失败，请重试"); } } 总结 Spring Boot集成Sentinel的关键点： ...