def create_issuing_service( reactor: IReactorTCP, acme_url: str, account_key_file: str, well_known_resource: IResource, ) -> AcmeIssuingService: """Create an ACME issuing service, and attach it to a web Resource Args: reactor: twisted reactor acme_url: URL to use to request certificates account_key_file: where to store the account key well_known_resource: web resource for .well-known. we will attach a child resource for "acme-challenge". Returns: AcmeIssuingService """ responder = HTTP01Responder() well_known_resource.putChild(b"acme-challenge", responder.resource) store = ErsatzStore() return AcmeIssuingService( cert_store=store, client_creator=(lambda: Client.from_url( reactor=reactor, url=URL.from_text(acme_url), key=load_or_create_client_key(account_key_file), alg=RS256, )), clock=reactor, responders=[responder], )