Update 2021-10-22: According to German authorities, it is possible that proof of at least one vaccination dose received is also required in Indonesia for travel across the borders of contiguous urban areas.
For air travel, a negative PCR test no more than 48 hours old is also required. For travel outside Bali and Java and areas classified by Indonesian authorities as risk categories 1 and 2, a rapid negative test no more than 24 hours old may be provided instead for air travel.