Conditional Requests

If-Unmodified-Since #

Endpoints that perform update operations support the conditional header If-Unmodified-Since.

If a request includes this header, then updates will be rejected if the stored resource has been modified since the date specified in the header, and a 412 Precondition Failed response will be returned.

The date should be in the format specified by RFC 2616.

If-Unmodified-Since: Wed, 21 Oct 2015 07:28:00 GMT