这是我参与8月更文挑战的第16天，活动详情查看：8月更文挑战
基于 API 分组限流
1、修改配置类，添加基于 API 分组限流的方法，修改初始化的限流参数
@Configuration
public class GatewayConfiguration {
private final List<ViewResolver> viewResolvers;
private final ServerCodecConfigurer serverCodecConfigurer;
public GatewayConfiguration(ObjectProvider<List<ViewResolver>> viewResolversProvider,
ServerCodecConfigurer serverCodecConfigurer) {
this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
this.serverCodecConfigurer = serverCodecConfigurer;
}
//配置限流的异常处理
@Bean
@Order(Ordered.HIGHEST_PRECEDENCE)
public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
}
//配置初始化的限流参数
@PostConstruct
public void initGatewayRules(){
Set<GatewayFlowRule> rules = new HashSet<>();
rules.add(new GatewayFlowRule("provider_api1").setCount(1).setIntervalSec(1));
rules.add(new GatewayFlowRule("provider_api2").setCount(1).setIntervalSec(1));
GatewayRuleManager.loadRules(rules);
}
//初始化限流过滤器
@Bean
@Order(Ordered.HIGHEST_PRECEDENCE)
public GlobalFilter sentinelGatewayFilter() {
return new SentinelGatewayFilter();
}
//自定义限流异常页面
@PostConstruct
public void initBlockHandlers(){
BlockRequestHandler blockRequestHandler = new BlockRequestHandler() {
@Override
public Mono<ServerResponse> handleRequest(ServerWebExchange serverWebExchange, Throwable throwable) {
Map map = new HashMap();
map.put("code",0);
map.put("msg","被限流了");
return ServerResponse.status(HttpStatus.OK)
.contentType(MediaType.APPLICATION_JSON)
.body(BodyInserters.fromObject(map));
}
};
GatewayCallbackManager.setBlockHandler(blockRequestHandler);
}
//自定义API分组
@PostConstruct
private void initCustomizedApis(){
Set<ApiDefinition> definitions = new HashSet<>();
ApiDefinition api1 = new ApiDefinition("provider_api1")
.setPredicateItems(new HashSet<ApiPredicateItem>(){{
add(new ApiPathPredicateItem().setPattern("/provider/api1/**")
.setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
}});
ApiDefinition api2 = new ApiDefinition("provider_api2")
.setPredicateItems(new HashSet<ApiPredicateItem>(){{
add(new ApiPathPredicateItem().setPattern("/provider/api2/demo1"));
}});
definitions.add(api1);
definitions.add(api2);
GatewayApiDefinitionManager.loadApiDefinitions(definitions);
}
}
2、Controller 添加方法
@GetMapping("/api1/demo1")
public String demo1(){
return "demo";
}
@GetMapping("/api1/demo2")
public String demo2(){
return "demo";
}
@GetMapping("/api2/demo1")
public String demo3(){
return "demo";
}
@GetMapping("/api2/demo2")
public String demo4(){
return "demo";
}
也可以基于 Nacos 服务发现组件进行限流
server:
port: 8010
spring:
application:
name: gateway
cloud:
gateway:
discovery:
locator:
enabled: true
API 分组代码修改，改为 discovery 中的服务名。
ApiDefinition api2 = new ApiDefinition("provider_api2")
.setPredicateItems(new HashSet<ApiPredicateItem>(){{
add(new ApiPathPredicateItem().setPattern("/p1/api2/demo1"));
}});
分布式事务
模拟分布式事务异常
1、创建两个工程 order、pay，pom.xml
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
2、建两个数据库 order、pay，两个微服务分别访问。
3、分别写两个服务的 application.yml
server:
port: 8010
spring:
application:
name: order
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
url: jdbc:mysql://localhost:3306/order
server:
port: 8020
spring:
application:
name: pay
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
url: jdbc:mysql://localhost:3306/pay
4、分别写两个 Service
@Service
public class OrderService {
@Autowired
private JdbcTemplate jdbcTemplate;
public void save(){
this.jdbcTemplate.update("insert into orders(username) values ('张三')");
}
}
@Service
public class PayService {
@Autowired
private JdbcTemplate jdbcTemplate;
public void save(){
this.jdbcTemplate.update("insert into pay(username) values ('张三')");
}
}
5、控制器 Order 通过 RestTemplate 调用 Pay 的服务
@RestController
public class OrderController {
@Autowired
private OrderService orderService;
@Autowired
private RestTemplate restTemplate;
@GetMapping("/save")
public String save(){
//订单
this.orderService.save();
int i = 10/0;
//支付
this.restTemplate.getForObject("http://localhost:8020/save",String.class);
return "success";
}
}
@RestController
public class PayController {
@Autowired
private PayService payService;
@GetMapping("/save")
public String save(){
this.payService.save();
return "success";
}
}
6、启动类
@SpringBootApplication
public class OrderApplication {
public static void main(String[] args) {
SpringApplication.run(OrderApplication.class, args);
}
@Bean
public RestTemplate restTemplate(){
return new RestTemplate();
}
}
@SpringBootApplication
public class PayApplication {
public static void main(String[] args) {
SpringApplication.run(PayApplication.class, args);
}
}
分布式异常模拟结束，Order 存储完成之后，出现异常，会导致 Pay 无法存储，但是 Order 数据库不会进行回滚。
