分布式接口冪等性、分布式限流總結(jié)整理

update set version = version +1 ,xxx=${xxx} where id =xxx and version = ${version};

    com.google.guava    guava    18.0

@RestController@Slf4jpublic class Controller{    //每秒鐘可以創(chuàng)建兩個令牌    RateLimiter limiter = RateLimiter.create(2.0);
    //非阻塞限流    @GetMapping("/tryAcquire")    public String tryAcquire(Integer count){        //count 每次消耗的令牌        if(limiter.tryAcquire(count)){            log.info("成功，允許通過，速率為{}",limiter.getRate());            return "success";        }else{            log.info("錯誤，不允許通過，速率為{}",limiter.getRate());            return "fail";        }    }
    //限定時間的非阻塞限流    @GetMapping("/tryAcquireWithTimeout")    public String tryAcquireWithTimeout(Integer count, Integer timeout){        //count 每次消耗的令牌  timeout 超時等待的時間        if(limiter.tryAcquire(count,timeout,TimeUnit.SECONDS)){            log.info("成功，允許通過，速率為{}",limiter.getRate());            return "success";        }else{            log.info("錯誤，不允許通過，速率為{}",limiter.getRate());            return "fail";        }    }
    //同步阻塞限流    @GetMapping("/acquire")    public String acquire(Integer count){        limiter.acquire(count);        log.info("成功，允許通過，速率為{}",limiter.getRate());        return "success";    }}

@RestController@Slf4jpublic class Controller{    //nginx測試使用    @GetMapping("/nginx")    public String nginx(){        log.info("Nginx success");    }}

127.0.0.1   www.test.com

vim /usr/local/nginx/conf/nginx.conf

#根據(jù)IP地址限制速度#1）$binary_remote_addr   binary_目的是縮寫內(nèi)存占用，remote_addr表示通過IP地址來限流#2）zone=iplimit:20m   iplimit是一塊內(nèi)存區(qū)域（記錄訪問頻率信息），20m是指這塊內(nèi)存區(qū)域的大小#3）rate=1r/s  每秒放行1個請求limit_req_zone $binary_remote_addr zone=iplimit:20m rate=1r/s;

server{    server_name www.test.com;    location /access-limit/ {        proxy_pass http://127.0.0.1:8080/;
        #基于ip地址的限制        #1）zone=iplimit 引用limit_rep_zone中的zone變量        #2）burst=2  設(shè)置一個大小為2的緩沖區(qū)域，當(dāng)大量請求到來，請求數(shù)量超過限流頻率時，將其放入緩沖區(qū)域        #3）nodelay   緩沖區(qū)滿了以后，直接返回503異常        limit_req zone=iplimit burst=2 nodelay;    }}

www.test.com/access-limit/nginx

#根據(jù)IP地址限制速度limit_req_zone $binary_remote_addr zone=iplimit:20m rate=10r/s;#根據(jù)服務(wù)器級別做限流limit_req_zone $server_name zone=serverlimit:10m rate=1r/s;#根據(jù)ip地址的鏈接數(shù)量做限流limit_conn_zone $binary_remote_addr zone=perip:20m;#根據(jù)服務(wù)器的連接數(shù)做限流limit_conn_zone $server_name zone=perserver:20m;
server{    server_name www.test.com;    location /access-limit/ {        proxy_pass http://127.0.0.1:8080/;
        #基于ip地址的限制        limit_req zone=iplimit burst=2 nodelay;        #基于服務(wù)器級別做限流        limit_req zone=serverlimit burst=2 nodelay;        #基于ip地址的鏈接數(shù)量做限流  最多保持100個鏈接        limit_conn zone=perip 100;        #基于服務(wù)器的連接數(shù)做限流 最多保持100個鏈接        limit_conn zone=perserver 1;        #配置request的異常返回504（默認(rèn)為503）        limit_req_status 504;        limit_conn_status 504;    }
     location /download/ {        #前100m不限制速度        limit_rate_affer 100m;        #限制速度為256k        limit_rate 256k;     }}

print?'Hello?Lua'

-- 模擬限流


-- 用作限流的keylocal key = 'my key'

-- 限流的最大閾值local limit = 2

-- 當(dāng)前限流大小local currentLimit = 2

-- 是否超過限流標(biāo)準(zhǔn)if currentLimit + 1 > limit then    print 'reject'    return falseelse    print 'accept'    return trueend

    org.springframework.boot    spring-boot-starter-data-redis    org.springframework.boot    spring-boot-starter-aop    com.google.guava    guava    18.0

server.port=8080

spring.redis.database=0spring.redis.host=localhostspring.redis.port=6376

-- 獲取方法簽名特征local methodKey = KEYS[1]redis.log(redis.LOG_DEBUG,'key is',methodKey)

-- 調(diào)用腳本傳入的限流大小local limit = tonumber(ARGV[1])

-- 獲取當(dāng)前流量大小local count = tonumber(redis.call('get',methodKey) or "0")

--是否超出限流值if count + 1 >limit then    -- 拒絕訪問    return falseelse    -- 沒有超過閾值    -- 設(shè)置當(dāng)前訪問數(shù)量+1    redis.call('INCRBY',methodKey,1)    -- 設(shè)置過期時間    redis.call('EXPIRE',methodKey,1)    -- 放行    return trueend

@Service@Slf4jpublic class AccessLimiter{    @Autowired    private StringRedisTemplate stringRedisTemplate;    @Autowired    private RedisScript rateLimitLua;

    public void limitAccess(String key,Integer limit){        boolean acquired = stringRedisTemplate.execute(            rateLimitLua,//lua腳本的真身            Lists.newArrayList(key),//lua腳本中的key列表            limit.toString()//lua腳本的value列表        );

        if(!acquired){            log.error("Your access is blocked,key={}",key);            throw new RuntimeException("Your access is blocked");        }    }}

@Configurationpublic class RedisConfiguration{    public RedisTemplate redisTemplate(RedisConnectionFactory factory){        return new StringRedisTemplate(factory);    }
    public DefaultRedisScript loadRedisScript(){        DefaultRedisScript redisScript = new DefaultRedisScript();        redisScript.setLocation(new ClassPathResource("rateLimiter.lua"));        redisScript.setResultType(java.lang.Boolean.class);        return redisScript;    }}

@RestController@Slf4jpublic class Controller{    @Autowired    private AccessLimiter accessLimiter;
    @GetMapping("test")    public String test(){        accessLimiter.limitAccess("ratelimiter-test",1);        return "success";    }}

@Target({ElementType.METHOD})@Retention(RetentionPolicy.RUNTIME)@Documentedpublic @interface AccessLimiterAop{    int limit();
    String methodKey() default "";}

@Slf4j@Aspect@Componentpublic class AccessLimiterAspect{    @Autowired    private AccessLimiter  accessLimiter;

    //根據(jù)注解的位置，自己修改    @Pointcut("@annotation(com.gyx.demo.annotation.AccessLimiter)")    public void cut(){        log.info("cut");    }
    @Before("cut()")    public void before(JoinPoint joinPoint){        //獲取方法簽名，作為methodkey        MethodSignature signature =(MethodSignature) joinPoint.getSignature();        Method method = signature.getMethod();        AccessLimiterAop annotation = method.getAnnotation(AccessLimiterAop.class);
        if(annotation == null){            return;        }        String key = annotation.methodKey();        Integer limit = annotation.limit();        //如果沒有設(shè)置methodKey，就自動添加一個        if(StringUtils.isEmpty(key)){            Class[] type = method.getParameterType();            key = method.getName();            if (type != null){                String paramTypes=Arrays.stream(type)                    .map(Class::getName)                    .collect(Collectors.joining(","));                    key += "#"+paramTypes;            }        }
        //調(diào)用redis        return accessLimiter.limitAccess(key,limit);    }}

@RestController@Slf4jpublic class Controller{    @Autowired    private AccessLimiter accessLimiter;
    @GetMapping("test")    @AccessLImiterAop(limit =1)    public String test(){        return "success";    }}