public async Task DkimSchedulerItemExistsDkimSchedulerItemsIsNotCreatedDkimEntityCreatedMessage()
        {
            A.CallTo(() => _dao.Get(A <string> ._))
            .Returns(new DkimSchedulerState(string.Empty));

            DkimEntityCreated message = new DkimEntityCreated("Domain", 1);

            await _handler.Handle(message);

            A.CallTo(() => _dao.Save(A <DkimSchedulerState> ._)).MustNotHaveHappened();
        }
        public async Task DkimSchedulerItemDoesntExistDkimSchedulerItemIsCreatedOnDkimEntityCreatedMessage()
        {
            A.CallTo(() => _dao.Get(A <string> ._))
            .Returns((DkimSchedulerState)null);

            DkimEntityCreated message = new DkimEntityCreated("Domain", 1);

            await _handler.Handle(message);

            A.CallTo(() => _dao.Save(A <DkimSchedulerState> ._)).MustHaveHappenedOnceExactly();
        }