Spring Cloud Gateway 原生支持接口限流該怎麼玩
關於Spring Cloud Gateway
SpringCloudGateway是spring官方基於Spring5.0,Spring Boot2.0 和Project Reactor等技術開發的網關,Spring雲網關旨在提供一種簡單高效的路由API的方法。Spring cloud 生態系的網關。目標是替代Netflix ZUUL, 其不僅提供統一的路由方式,並且基於Filter鏈的方式提供了網關的基本功能,例如: 安全,監控/埋點,和限流等
Zuul:構建高可用網關之多維度限流
開始Gateway的限流
pom依賴
<!--spring cloud gateway依賴-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<!--基於 reactive stream 的redis -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis-reactive</artifactId>
</dependency>
按照請求的ip限流
spring:
cloud:
gateway:
routes:
- id: requestratelimiter_route
uri: lb://pigx-upms
order: 10000
predicates:
- Path=/admin/**
filters:
- name: RequestRateLimiter
args:
redis-rate-limiter.replenishRate: 1 # 令牌桶的容積
redis-rate-limiter.burstCapacity: 3 # 流速 每秒
key-resolver: "#{@remoteAddrKeyResolver}" #SPEL表達式去的對應的bean
- StripPrefix=1
所有關於admin 的請求都會轉發過來 , - StripPrefix=1 去掉admin 如
http://localhost:8080/admin/api/user => http://pigx-upms:8081/api/user
配置bean
在啓動類配置
/**
*自定義限流標誌的key,多個維度可以從這裏入手
*exchange對象中獲取服務ID,請求信息,用戶信息等
*/
@Bean
KeyResolver remoteAddrkeyResolver(){
return exchange -> Mono.just(
exchange.getRequest.getRemoteAddress().getHostName());
}
ok完成
壓力測試
開發5個線程
Redis數據變化
我們使用redis的monitor命令,實時查看redis的操作情況
會發現在redis中會操作2個key
request_rate_limiter.{xxx}.timestamp
request_rate_limiter.{xxx}.tokens
實現原理
spring cloud Gateway 默認實現Redis限流,如果擴展只需要實現ratelimter接口既可
RedisRateLimter 的核心代碼,判斷是否取到令牌的實現,通過調用 redis的LUA 腳本。
public Mono<Response> isAllowed(String routeId, String id) {
Config routeConfig = getConfig().getOrDefault(routeId, defaultConfig);
int replenishRate = routeConfig.getReplenishRate();
int burstCapacity = routeConfig.getBurstCapacity();
try {
List<String> keys = getKeys(id);
returns unixtime in seconds.
List<String> scriptArgs = Arrays.asList(replenishRate + "", burstCapacity + "",
Instant.now().getEpochSecond() + "", "1");
// 這裏是核心,執行redis 的LUA 腳本。
Flux<List<Long>> flux =
this.redisTemplate.execute(this.script, keys, scriptArgs);
return flux.onErrorResume(throwable -> Flux.just(Arrays.asList(1L, -1L)))
.reduce(new ArrayList<Long>(), (longs, l) -> {
longs.addAll(l);
return longs;
}) .map(results -> {
boolean allowed = results.get(0) == 1L;
Long tokensLeft = results.get(1);
Response response = new Response(allowed, getHeaders(routeConfig, tokensLeft));
if (log.isDebugEnabled()) {
log.debug("response: " + response);
}
return response;
});
}
catch (Exception e) {
log.error("Error determining if user allowed from redis", e);
}
return Mono.just(new Response(true, getHeaders(routeConfig, -1L)));
}