gateway整合sentinel实现服务流控熔断降级

1.在gateway服务模块中添加gateway整合sentinel的依赖

    com.alibaba.cloud
    spring-cloud-alibaba-sentinel-gateway




    com.alibaba.cloud
    spring-cloud-starter-alibaba-sentinel

2. 在application.yml配置文件中添加sentinel控制台的配置

sentinel:  #sentinel的配置
  transport:
    dashboard: localhost:8080  #配置sentinel dashboard地址
    port:  8719   #默认端口8719

3. 编写gateway配置类，自定义限流配置

package com.mc.tutor.config;

import com.alibaba.csp.sentinel.adapter.gateway.common.SentinelGatewayConstants;
import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPathPredicateItem;
import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPredicateItem;
import com.alibaba.csp.sentinel.adapter.gateway.common.api.GatewayApiDefinitionManager;
import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.BlockRequestHandler;
import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.GatewayCallbackManager;

import com.mc.tutor.common.ResponseResult;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.web.reactive.function.BodyInserters;
import org.springframework.web.reactive.function.server.ServerResponse;


import javax.annotation.PostConstruct;
import java.util.HashSet;
import java.util.Set;

/**
 * @ClassName GatewayConfig
 * @Description 网关配置
 * @Author PotatoBoy
 * @Date 2021/11/9 21:00
 * @Version 1.0
 **/
@Configuration
public class GatewayConfig {

    /*
     * @Author PotatoBoy
     * @Description //初始化限流配置
     * @Date 2021/11/19 15:10
     * @Param []
     * @return void
     **/
    @PostConstruct
    public void init() {

        initCustomizedApis();

        initBlockHandler();
    }

    /*
     * @Author PotatoBoy
     * @Description //自定义api分组
     * @Date 2021/11/19 15:12
     * @Param []
     * @return void
     **/
    private void initCustomizedApis() {
        Set definitions = new HashSet<>();
        ApiDefinition api = new ApiDefinition("user-center")
                .setPredicateItems(new HashSet() {{
                    add(new ApiPathPredicateItem().setPattern("/user-center/**")
                    .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
                }});

        definitions.add(api);
        //加载自定义的限流分组
        GatewayApiDefinitionManager.loadApiDefinitions(definitions);
    }


    /*
     * @Author PotatoBoy
     * @Description //自定义限流异常处理器
     * @Date 2021/11/19 15:09
     * @Param 
     * @return 
     **/
    private void initBlockHandler() {
        BlockRequestHandler blockRequestHandler = (serverWebExchange, throwable) ->
                ServerResponse.status(HttpStatus.TOO_MANY_REQUESTS)
                        .contentType(MediaType.APPLICATION_JSON)
                        .body(BodyInserters.fromValue(ResponseResult.sendFailMsg("您的请求过于频繁，请稍后再试！")));

        // 加载自定义的限流异常处理器
        GatewayCallbackManager.setBlockHandler(blockRequestHandler);
    }
}