@Override
    public void upgrade() {
        try {
            streamService.load(Stream.DEFAULT_STREAM_ID);
        } catch (NotFoundException ignored) {
            createDefaultStream();
        }
    }
@Test
    public void upgradeDoesNotRunIfDefaultStreamExists() throws Exception {
        when(streamService.load("000000000000000000000001")).thenReturn(mock(Stream.class));

        migration.upgrade();

        verify(streamService, never()).save(any(Stream.class));
    }