52 lines
1.4 KiB
TypeScript
52 lines
1.4 KiB
TypeScript
import { Redis } from "ioredis";
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export class SlidingWindow {
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private redis: Redis;
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private readonly windowSize: number;
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/*
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* Create a new sliding window
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* @param redisClient The Redis client used to store the data
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* @param windowSize The size of the window in seconds
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*/
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constructor(redisClient: Redis, windowSize: number) {
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this.redis = redisClient;
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this.windowSize = windowSize * 1000;
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}
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/*
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* Trigger an event in the sliding window
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* @param eventName The name of the event
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*/
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async event(eventName: string): Promise<void> {
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const now = Date.now();
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const key = `cvsa:sliding_window:${eventName}`;
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const uniqueMember = `${now}-${Math.random()}`;
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// Add current timestamp to an ordered set
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await this.redis.zadd(key, now, uniqueMember);
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// Remove timestamps outside the window
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await this.redis.zremrangebyscore(key, 0, now - this.windowSize);
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}
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/*
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* Count the number of events in the sliding window
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* @param eventName The name of the event
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*/
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async count(eventName: string): Promise<number> {
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const key = `cvsa:sliding_window:${eventName}`;
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const now = Date.now();
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// Remove timestamps outside the window
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await this.redis.zremrangebyscore(key, 0, now - this.windowSize);
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// Get the number of timestamps in the window
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return this.redis.zcard(key);
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}
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clear(eventName: string): Promise<number> {
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const key = `cvsa:sliding_window:${eventName}`;
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return this.redis.del(key);
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}
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}
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