自适应限流

桃扇骨 2023-06-17 06:57 13阅读 0赞

**pom.xml**

<?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 https://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>2.2.1.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.xxxx</groupId>
        <artifactId>sentinel</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>sentinel</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
                <exclusions>
                    <exclusion>
                        <groupId>org.junit.vintage</groupId>
                        <artifactId>junit-vintage-engine</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
    
            <dependency>
                <groupId>com.alibaba.csp</groupId>
                <artifactId>sentinel-annotation-aspectj</artifactId>
                <version>1.7.0</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba.csp</groupId>
                <artifactId>sentinel-core</artifactId>
                <version>1.7.0</version>
            </dependency>
    
            <dependency>
                <groupId>com.alibaba.csp</groupId>
                <artifactId>sentinel-transport-simple-http</artifactId>
                <version>1.7.0</version>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    </project>

**SentileConfig.java**

package com.xxxx.sentinel.config;
    
    import com.alibaba.csp.sentinel.Entry;
    import com.alibaba.csp.sentinel.EntryType;
    import com.alibaba.csp.sentinel.SphU;
    import com.alibaba.csp.sentinel.annotation.aspectj.SentinelResourceAspect;
    import com.alibaba.csp.sentinel.slots.block.BlockException;
    import com.alibaba.csp.sentinel.slots.system.SystemRule;
    import com.alibaba.csp.sentinel.slots.system.SystemRuleManager;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import javax.annotation.PostConstruct;
    import java.util.ArrayList;
    import java.util.Collections;
    import java.util.List;
    import java.util.concurrent.atomic.AtomicInteger;
    
    
    /** * @author nick */
    @Configuration
    public class SentileConfig { 
    
        private static AtomicInteger pass = new AtomicInteger();
        private static AtomicInteger block = new AtomicInteger();
        private static AtomicInteger total = new AtomicInteger();
    
        @Bean
        public SentinelResourceAspect sentinelResourceAspect() { 
            return new SentinelResourceAspect();
        }
    
        @PostConstruct
        private void initRules() throws Exception { 
            //自适应服务器限流
            List<SystemRule> rules = new ArrayList<SystemRule>();
            SystemRule rule = new SystemRule();
            // 设置最高系统负载
            rule.setHighestSystemLoad(3.0);
            // 设置最大cpu负载60%
            rule.setHighestCpuUsage(0.6);
            // 设置最大平均请求响应时间 10 ms
            rule.setAvgRt(10);
            // 设置最大qps是20
            rule.setQps(20);
            // 设置最大线程数 10
            rule.setMaxThread(10);
            rules.add(rule);
            SystemRuleManager.loadRules(Collections.singletonList(rule));
    
            //设置方法上进行入口限流
            Entry entry = null;
            try { 
                entry = SphU.entry("ok", EntryType.IN);
                pass.incrementAndGet();
            } catch (BlockException e1) { 
                block.incrementAndGet();
            } catch (Exception e2) { 
            } finally { 
                total.incrementAndGet();
                if (entry != null) { 
                    entry.exit();
                }
            }
        }
    }

**TestController.java**

package com.xxxx.sentinel;
    
    import com.alibaba.csp.sentinel.annotation.SentinelResource;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    /** * @author nick */
    @RestController
    public class TestController { 
    
    
        @GetMapping("ok")
        @SentinelResource(fallback = "error")
        public String ok(String name){ 
            return "ok,"+name;
        }
    
        public String error(String name){ 
            return "error,"+name;
        }
    
    }

**SentinelApplication.java**

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SentinelApplication { 
    
        public static void main(String[] args) { 
            SpringApplication.run(SentinelApplication.class, args);
        }
    
    }