47 lines
1.3 KiB
TypeScript
47 lines
1.3 KiB
TypeScript
import { Redis } from "ioredis";
|
|
|
|
export class SlidingWindow {
|
|
private redis: Redis;
|
|
private readonly windowSize: number;
|
|
|
|
constructor(redisClient: Redis, windowSize: number) {
|
|
this.redis = redisClient;
|
|
this.windowSize = windowSize;
|
|
}
|
|
|
|
/*
|
|
* Trigger an event in the sliding window
|
|
* @param eventName The name of the event
|
|
*/
|
|
async event(eventName: string): Promise<void> {
|
|
const now = Date.now();
|
|
const key = `cvsa:sliding_window:${eventName}`;
|
|
|
|
const uniqueMember = `${now}-${Math.random()}`;
|
|
// Add current timestamp to an ordered set
|
|
await this.redis.zadd(key, now, uniqueMember);
|
|
|
|
// Remove timestamps outside the window
|
|
await this.redis.zremrangebyscore(key, 0, now - this.windowSize);
|
|
}
|
|
|
|
/*
|
|
* Count the number of events in the sliding window
|
|
* @param eventName The name of the event
|
|
*/
|
|
async count(eventName: string): Promise<number> {
|
|
const key = `cvsa:sliding_window:${eventName}`;
|
|
const now = Date.now();
|
|
|
|
// Remove timestamps outside the window
|
|
await this.redis.zremrangebyscore(key, 0, now - this.windowSize);
|
|
// Get the number of timestamps in the window
|
|
return this.redis.zcard(key);
|
|
}
|
|
|
|
async clear(eventName: string): Promise<number> {
|
|
const key = `cvsa:sliding_window:${eventName}`;
|
|
return await this.redis.del(key);
|
|
}
|
|
}
|