SpringCloud網關如何實作限流？ | 帶你讀《Spring Cloud Alibaba（2019）》之十五

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本文來自于《精通Spring Cloud Alibaba》課程的整理，講師為餘勝軍，

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SpringCloud網關如何整合sentinel實作限流

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介紹 網關限流

相關核心配置

Maven依賴配置

<dependency>
      <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
            <version>2.0.0.RELEASE</version>
</dependency>
<dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-spring-cloud-gateway-adapter</artifactId>
            <version>1.6.0</version>
</dependency>           

gateway:
  routes:
    - id: my-member
      uri: lb://meitemayikt-member
      predicates:
        - Path=/meitemayikt-member/**
    - id: mayikt
      uri: http://www.mayikt.com
      predicates:
        - Path=/mayikt/**           

import com.alibaba.csp.sentinel.adapter.gateway.sc.SentinelGatewayFilter;
import com.alibaba.csp.sentinel.adapter.gateway.sc.exception.SentinelGatewayBlockExceptionHandler;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.codec.ServerCodecConfigurer;
import org.springframework.web.reactive.result.view.ViewResolver;

import java.util.Collections;
import java.util.List;

@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;
    }

    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        // Register the block exception handler for Spring Cloud Gateway.
        return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
    }

    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public GlobalFilter sentinelGatewayFilter() {
        return new SentinelGatewayFilter();
    }
}           

加載網關流控規則

@Slf4j
@Component
public class SentinelApplicationRunner implements ApplicationRunner {

    @Override
    public void run(ApplicationArguments args) throws Exception {
        initGatewayRules();

    }

    /**
     * 配置限流規則
     */
    private void initGatewayRules() {
        Set<GatewayFlowRule> rules = new HashSet<>();
        rules.add(new GatewayFlowRule("mayikt")
                // 限流門檻值
                .setCount(1)
                // 統計時間視窗，機關是秒，預設是 1 秒
                .setIntervalSec(1)
        );
        GatewayRuleManager.loadRules(rules);
    }
}           

如何修改限流錯誤提示

public class JsonSentinelGatewayBlockExceptionHandler implements WebExceptionHandler {
    public JsonSentinelGatewayBlockExceptionHandler(List<ViewResolver> viewResolvers, ServerCodecConfigurer serverCodecConfigurer) {
    }

    @Override
    public Mono<Void> handle(ServerWebExchange exchange, Throwable ex) {
        ServerHttpResponse serverHttpResponse = exchange.getResponse();
        serverHttpResponse.getHeaders().add("Content-Type", "application/json;charset=UTF-8");
        byte[] datas = "{\"code\":403,\"msg\":\"API接口被限流\"}".getBytes(StandardCharsets.UTF_8);
        DataBuffer buffer = serverHttpResponse.bufferFactory().wrap(datas);
        return serverHttpResponse.writeWith(Mono.just(buffer));
    }
}           

@Bean
@Order(Ordered.HIGHEST_PRECEDENCE)
public JsonSentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
    // Register the block exception handler for Spring Cloud Gateway.
    return new JsonSentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
}           

執行結果：