89 lines
2.1 KiB
TypeScript
89 lines
2.1 KiB
TypeScript
import { kv } from '@vercel/kv';
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/**
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* Rate limit configuration
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*/
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const RATE_LIMIT_WINDOW = 60 * 60 * 1000; // 1 hour in milliseconds
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const MAX_REQUESTS_PER_WINDOW = 5;
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/**
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* Rate limit key prefix
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*/
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const RATE_LIMIT_PREFIX = 'ratelimit:signup:';
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/**
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* Check if an IP address has exceeded rate limits
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* @param identifier - IP address or unique identifier
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* @returns Object with allowed status and retry information
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*/
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export async function checkRateLimit(identifier: string): Promise<{
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allowed: boolean;
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remaining: number;
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resetAt: number;
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}> {
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const key = `${RATE_LIMIT_PREFIX}${identifier}`;
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const now = Date.now();
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try {
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// Get current count
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const count = await kv.get<number>(key) || 0;
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if (count >= MAX_REQUESTS_PER_WINDOW) {
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// Get TTL to determine reset time
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const ttl = await kv.ttl(key);
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const resetAt = now + (ttl * 1000);
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return {
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allowed: false,
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remaining: 0,
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resetAt,
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};
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}
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// Increment counter
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const newCount = count + 1;
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if (count === 0) {
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// First request - set with expiry
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await kv.set(key, newCount, {
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px: RATE_LIMIT_WINDOW,
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});
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} else {
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// Subsequent request - increment without changing TTL
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await kv.incr(key);
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}
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// Calculate reset time
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const ttl = await kv.ttl(key);
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const resetAt = now + (ttl * 1000);
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return {
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allowed: true,
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remaining: MAX_REQUESTS_PER_WINDOW - newCount,
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resetAt,
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};
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} catch (error) {
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// If rate limiting fails, allow the request
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console.error('Rate limit check failed:', error);
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return {
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allowed: true,
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remaining: MAX_REQUESTS_PER_WINDOW,
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resetAt: now + RATE_LIMIT_WINDOW,
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};
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}
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}
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/**
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* Get client IP from request headers
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*/
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export function getClientIp(request: Request): string {
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// Try various headers that might contain the IP
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const headers = request.headers;
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return (
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headers.get('x-forwarded-for')?.split(',')[0]?.trim() ||
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headers.get('x-real-ip') ||
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headers.get('cf-connecting-ip') || // Cloudflare
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'unknown'
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);
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} |