zuul集成Sentinel,完成對(duì)path映射的限流操作

更新時(shí)間：2021年06月25日 11:15:41 作者：天涯淚小武

這篇文章主要介紹了zuul集成Sentinel,完成對(duì)path映射的限流操作，具有很好的參考價(jià)值，希望對(duì)大家有所幫助。如有錯(cuò)誤或未考慮完全的地方，望不吝賜教

zuul集成Sentinel完成對(duì)path映射的限流

前面我們講過(guò)了對(duì)單體應(yīng)用的Sentinel限流，以及使用zookeeper對(duì)規(guī)則的持久化。通過(guò)前面的工作，我們可以完成單個(gè)實(shí)例的細(xì)粒度的限流、熔斷操作。

譬如有一個(gè)服務(wù)User，在分布式環(huán)境下，開(kāi)啟了多個(gè)實(shí)例，那么每個(gè)實(shí)例都可以獲得如每秒限制10個(gè)登錄的限流功能。但是有些場(chǎng)景下，我們想要另外一種限流方式，譬如在網(wǎng)關(guān)zuul層，想限制對(duì)User服務(wù)的限流，而不去關(guān)心具體它有多少個(gè)實(shí)例。這時(shí)，就需要用到網(wǎng)關(guān)限流了。

Sentinel 1.6.0 引入了 Sentinel API Gateway Adapter Common 模塊，包含網(wǎng)關(guān)限流的規(guī)則和自定義 API 的實(shí)體和管理邏輯：

GatewayFlowRule：網(wǎng)關(guān)限流規(guī)則，針對(duì) API Gateway 的場(chǎng)景定制的限流規(guī)則，可以針對(duì)不同 route 或自定義的 API 分組進(jìn)行限流，支持針對(duì)請(qǐng)求中的參數(shù)、Header、來(lái)源 IP 等進(jìn)行定制化的限流。

ApiDefinition：用戶自定義的 API 定義分組，可以看做是一些 URL 匹配的組合。比如我們可以定義一個(gè) API 叫 my_api，請(qǐng)求 path 模式為 /foo/** 和 /baz/** 的都?xì)w到 my_api 這個(gè) API 分組下面。

限流的時(shí)候可以針對(duì)這個(gè)自定義的 API 分組維度進(jìn)行限流。

注意這個(gè)版本，1.6.0以后才有的。

我們直接上代碼，進(jìn)入實(shí)戰(zhàn)。新建一個(gè)SpringCloud項(xiàng)目，選中zuul。并在啟動(dòng)類(lèi)上加上@EnableZuulProxy注解，代表這是一個(gè)zuul網(wǎng)關(guān)項(xiàng)目。

pom.xml如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>sentinelzuul</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>sentinelzuul</name>
    <description>Demo project for Spring Boot</description>
 
    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
        <sentinel.version>1.6.1</sentinel.version>
    </properties>
 
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
        </dependency>
        <!--<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-datasource-zookeeper</artifactId>
        </dependency>-->
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-zuul-adapter</artifactId>
            <version>${sentinel.version}</version>
        </dependency>
 
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-core</artifactId>
            <version>${sentinel.version}</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-parameter-flow-control</artifactId>
            <version>${sentinel.version}</version>
        </dependency>
 
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
 
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
 
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>0.2.2.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
 
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
 
</project>

官方文檔上寫(xiě)，只需要引入sentinel-zuul-adapter依賴，實(shí)測(cè)后發(fā)現(xiàn)，只引入這個(gè)的話，所依賴的Sentinel-core是1.5.2版本，會(huì)導(dǎo)致啟動(dòng)失敗。所以我手工加入了其他幾個(gè)依賴。

yml文件如下：

server:
  port: 9999
zuul:
  routes:
    one:
      path: /baoban/**
      url: http://localhost:8888/baoban/
spring:
  application:
    name: sentinelzuul

這里配了一個(gè)簡(jiǎn)單的routes映射。那是另外一個(gè)本地服務(wù)。

使用zuul的限流很簡(jiǎn)單，2個(gè)類(lèi)即可

ZuulConfig.java

import com.alibaba.csp.sentinel.adapter.gateway.zuul.filters.SentinelZuulErrorFilter;
import com.alibaba.csp.sentinel.adapter.gateway.zuul.filters.SentinelZuulPostFilter;
import com.alibaba.csp.sentinel.adapter.gateway.zuul.filters.SentinelZuulPreFilter;
import com.netflix.zuul.ZuulFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
/**
 * @author wuweifeng wrote on 2019/7/3.
 */
@Configuration
public class ZuulConfig {
 
    @Bean
    public ZuulFilter sentinelZuulPreFilter() {
        return new SentinelZuulPreFilter(10000);
    }
 
    @Bean
    public ZuulFilter sentinelZuulPostFilter() {
        return new SentinelZuulPostFilter(1000);
    }
 
    @Bean
    public ZuulFilter sentinelZuulErrorFilter() {
        return new SentinelZuulErrorFilter(-1);
    }
}

package com.example.sentinelzuul.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.common.rule.GatewayFlowRule;
import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayParamFlowItem;
import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayRuleManager;
import com.alibaba.csp.sentinel.slots.block.RuleConstant;
import org.springframework.context.annotation.Configuration; 
import javax.annotation.PostConstruct;
import java.util.HashSet;
import java.util.Set;
 
/**
 * @author wuweifeng wrote on 2019/7/3.
 */
@Configuration
public class GatewayRuleConfig {
    private static final int URL_MATCH_STRATEGY_EXACT = 0;
    private static final int URL_MATCH_STRATEGY_PREFIX = 1;
    private static final int URL_MATCH_STRATEGY_REGEX = 2;
 
    @PostConstruct
    public void doInit() {
        // Prepare some gateway rules and API definitions (only for demo).
        // It's recommended to leverage dynamic data source or the Sentinel dashboard to push the rules.
        initCustomizedApis();
        initGatewayRules();
    }
 
    private void initCustomizedApis() {
        Set<ApiDefinition> definitions = new HashSet<>();
        ApiDefinition api1 = new ApiDefinition("baobao_api")
                .setPredicateItems(new HashSet<ApiPredicateItem>() {{
                    //add(new ApiPathPredicateItem().setPattern("/ahas"));
                    add(new ApiPathPredicateItem().setPattern("/baoban/**")
                            .setMatchStrategy(URL_MATCH_STRATEGY_PREFIX));
                }});
        //ApiDefinition api2 = new ApiDefinition("another_customized_api")
        //        .setPredicateItems(new HashSet<ApiPredicateItem>() {{
        //            add(new ApiPathPredicateItem().setPattern("/**")
        //                    .setMatchStrategy(URL_MATCH_STRATEGY_PREFIX));
        //        }});
        definitions.add(api1);
        //definitions.add(api2);
        GatewayApiDefinitionManager.loadApiDefinitions(definitions);
    }
 
    private void initGatewayRules() {
        Set<GatewayFlowRule> rules = new HashSet<>();
        rules.add(new GatewayFlowRule("baobao_api")
                .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
                .setCount(1)
                .setIntervalSec(1)
        );
        rules.add(new GatewayFlowRule("aliyun-product-route")
                .setCount(2)
                .setIntervalSec(2)
                //應(yīng)對(duì)突發(fā)請(qǐng)求時(shí)額外允許的請(qǐng)求數(shù)目。
                .setBurst(2)
                .setParamItem(new GatewayParamFlowItem()
                        .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_CLIENT_IP)
                )
        );
        rules.add(new GatewayFlowRule("another-route-httpbin")
                .setCount(10)
                //統(tǒng)計(jì)時(shí)間窗口，單位是秒，默認(rèn)是 1 秒。
                .setIntervalSec(1)
                //流量整形的控制效果，同限流規(guī)則的 controlBehavior 字段，目前支持快速失敗和勻速排隊(duì)兩種模式，默認(rèn)是快速失敗。
                .setControlBehavior(RuleConstant.CONTROL_BEHAVIOR_RATE_LIMITER)
                //勻速排隊(duì)模式下的最長(zhǎng)排隊(duì)時(shí)間，單位是毫秒，僅在勻速排隊(duì)模式下生效。
                .setMaxQueueingTimeoutMs(600)
                //參數(shù)限流配置
                .setParamItem(new GatewayParamFlowItem()
                        .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_HEADER)
                        .setFieldName("X-Sentinel-Flag")
                )
        );
        rules.add(new GatewayFlowRule("another-route-httpbin")
                .setCount(1)
                .setIntervalSec(1)
                .setParamItem(new GatewayParamFlowItem()
                        .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                        .setFieldName("pa")
                )
        );
 
        rules.add(new GatewayFlowRule("some_customized_api")
                .setResourceMode(SentinelGatewayConstants.RESOURCE_MODE_CUSTOM_API_NAME)
                .setCount(5)
                .setIntervalSec(1)
                .setParamItem(new GatewayParamFlowItem()
                        .setParseStrategy(SentinelGatewayConstants.PARAM_PARSE_STRATEGY_URL_PARAM)
                        .setFieldName("pn")
                )
        );
        GatewayRuleManager.loadRules(rules);
 
        //監(jiān)聽(tīng)zookeeper，使用zookeeper的規(guī)則
        //ReadableDataSource<String, Set<GatewayFlowRule>> flowRuleDataSource = new ZookeeperDataSource<>(null, null,
        //        source -> JSON.parseObject(source, new TypeReference<Set<GatewayFlowRule>>() {
        //        }));
        //GatewayRuleManager.register2Property(flowRuleDataSource.getProperty());
    }
}

主要做的有2件事

1是配置一下APIDefinition，也就是給自己的映射規(guī)則起個(gè)名字。

2是配置Rule，和之前的配置rule差不多。創(chuàng)建一個(gè)rule的集合，設(shè)置rule規(guī)則，具體規(guī)則各字段在上面截圖中有解釋。

這里我配了一個(gè)簡(jiǎn)單的一秒1個(gè)QPS的規(guī)則。最后用GatewayRuleManager去loadRules即可。

之后測(cè)試一下就發(fā)現(xiàn)規(guī)則已生效。頻繁訪問(wèn)被限流的服務(wù)時(shí)，會(huì)報(bào)下面的異常。

如果你想自定義這個(gè)熔斷的返回值的話，可以加個(gè)類(lèi)實(shí)現(xiàn)ZuulBlockFallbackProvider：

import com.alibaba.csp.sentinel.adapter.gateway.zuul.fallback.BlockResponse;
import com.alibaba.csp.sentinel.adapter.gateway.zuul.fallback.DefaultBlockFallbackProvider;
import com.alibaba.csp.sentinel.adapter.gateway.zuul.fallback.ZuulBlockFallbackProvider;
import com.alibaba.csp.sentinel.log.RecordLog;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
 
/**
 * @author wuweifeng wrote on 2019/7/3.
 */
public class MyBlockFallbackProvider implements ZuulBlockFallbackProvider {
 
    private Logger logger = LoggerFactory.getLogger(DefaultBlockFallbackProvider.class);
 
    // you can define route as service level
    @Override
    public String getRoute() {
        return "baobao_api";
    }
 
    @Override
    public BlockResponse fallbackResponse(String route, Throwable cause) {
        RecordLog.info(String.format("[Sentinel DefaultBlockFallbackProvider] Run fallback route: %s", route));
        if (cause instanceof BlockException) {
            return new BlockResponse(429, "the route is blocked", route);
        } else {
            return new BlockResponse(500, "System Error", route);
        }
    }
}

getRoute方法返回的就是上面定義的resouceName。然后注冊(cè)一下就好了。