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import type { AppContext } from "@/worker/types";
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import { hashNullable } from "@/worker/util/request-context";
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import { jsonError } from "@/worker/util/response";
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export type RateLimitBinding = "RL_AUTH" | "RL_DAV_AUTH" | "RL_REPORT";
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export async function rateLimitKey(parts: (string | null | undefined)[]): Promise<string> {
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  return (await hashNullable(parts.filter((part): part is string => !!part).join(":"))) ?? "unknown";
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}
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export async function enforceRateLimit(
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  c: AppContext,
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  binding: RateLimitBinding,
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  keyParts: (string | null | undefined)[],
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): Promise<Response | null> {
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  if (import.meta.env.DEV) return null;
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  const key = await rateLimitKey(keyParts);
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  const { success } = await c.env[binding].limit({ key });
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  return success ? null : jsonError("rate_limited", "Too many requests.", 429);
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}