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import type { FetchFunction } from './interfaces.d.ts'import { JOSEError, JWKSTimeout } from '../util/errors.ts'
type AcceptedRequestOptions = Pick<RequestInit, 'headers'>
const fetchJwks: FetchFunction = async (  url: URL,  timeout: number,  options: AcceptedRequestOptions,) => {  let controller!: AbortController  let id!: ReturnType<typeof setTimeout>  let timedOut = false  if (typeof AbortController === 'function') {    controller = new AbortController()    id = setTimeout(() => {      timedOut = true      controller.abort()    }, timeout)  }
  const response = await fetch(url.href, {    signal: controller ? controller.signal : undefined,    redirect: 'manual',    headers: options.headers,  }).catch((err) => {    if (timedOut) throw new JWKSTimeout()    throw err  })
  if (id !== undefined) clearTimeout(id)
  if (response.status !== 200) {    throw new JOSEError('Expected 200 OK from the JSON Web Key Set HTTP response')  }
  try {    return await response.json()  } catch {    throw new JOSEError('Failed to parse the JSON Web Key Set HTTP response as JSON')  }}export default fetchJwks