34 lines
1 KiB
TypeScript
34 lines
1 KiB
TypeScript
type Bucket = { count: number; resetAt: number };
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const buckets = new Map<string, Bucket>();
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const MAX_BUCKETS = 10_000;
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export function requestIp(req: Request): string {
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// The deployment binds Next.js to localhost behind a reverse proxy. The
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// proxy must replace client-supplied forwarding headers for this to be safe.
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return (
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req.headers.get("x-real-ip") ||
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req.headers.get("x-forwarded-for")?.split(",")[0]?.trim() ||
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"unknown"
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);
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}
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export function rateLimit(key: string, max: number, windowMs: number): boolean {
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const now = Date.now();
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const current = buckets.get(key);
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if (!current || current.resetAt <= now) {
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if (buckets.size >= MAX_BUCKETS) {
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for (const [bucketKey, bucket] of buckets) {
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if (bucket.resetAt <= now) buckets.delete(bucketKey);
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}
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if (buckets.size >= MAX_BUCKETS) buckets.delete(buckets.keys().next().value as string);
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}
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buckets.set(key, { count: 1, resetAt: now + windowMs });
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return true;
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}
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if (current.count >= max) return false;
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current.count += 1;
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return true;
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}
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