txacme.service module

class txacme.service.AcmeIssuingService(cert_store, client_creator, clock, responders, email=None, check_interval=datetime.timedelta(1), reissue_interval=datetime.timedelta(30), panic_interval=datetime.timedelta(15), panic=<function _default_panic>, generate_key=<functools.partial object>)[source]

A service for keeping certificates up to date by using an ACME server.

  • cert_store (ICertificateStore) – The certificate store containing the certificates to manage.
  • client_creator (Callable[[], Deferred[txacme.client.Client]]) – A callable called with no arguments for creating the ACME client. For example, partial(Client.from_url, reactor=reactor, url=LETSENCRYPT_STAGING_DIRECTORY, key=acme_key, alg=RS256).
  • clockIReactorTime provider; usually the reactor, when not testing.
  • responders (List[IResponder]) – Challenge responders. Usually only one responder is needed; if more than one responder for the same type is provided, only the first will be used.
  • email (str) – An (optional) email address to use during registration.
  • check_interval (timedelta) – How often to check for expiring certificates.
  • reissue_interval (timedelta) – If a certificate is expiring in less time than this interval, it will be reissued.
  • panic_interval (timedelta) – If a certificate is expiring in less time than this interval, and reissuing fails, the panic callback will be invoked.
  • panic (Callable[[Failure, str], Deferred]) – A callable invoked with the failure and server name when reissuing fails for a certificate expiring in the panic_interval. For example, you could generate a monitoring alert. The default callback logs a message at CRITICAL level.
  • generate_key – A 0-arg callable used to generate a private key for a new cert. Normally you would not pass this unless you have specialized key generation requirements.

Issue a new cert for a particular name.

If an existing cert exists, it will be replaced with the new cert. If issuing is already in progress for the given name, a second issuing process will not be started.

Parameters:server_name (str) – The name to issue a cert for.
Return type:Deferred
Returns:A deferred that fires when issuing is complete.

Get a notification once the startup check has completed.

When the service starts, an initial check is made immediately; the deferred returned by this function will only fire once reissue has been attempted for any certificates within the panic interval.


The reissue for any of these certificates may not have been successful; the panic callback will be invoked for any certificates in the panic interval that failed reissue.

Return type:Deferred
Returns:A deferred that fires once the initial check has resolved.