def fix_previous_block(block, chain):
logger.info('fixing previous block for {}'.format(block))
prev_hash = get_block_hash(block.height - 1, schema_name=chain)
if not prev_hash:
return
try:
prev_block = Block.objects.get(hash=prev_hash)
except Block.DoesNotExist:
prev_block = Block(hash=prev_hash)
try:
prev_height_block = Block.objects.get(height=block.height - 1)
except Block.DoesNotExist:
prev_height_block = prev_block
if prev_block != prev_height_block:
# the block with the previous height doesn't match the hash from this block
# likely to be an orphan so remove it
prev_height_block.delete()
block.previous_block = prev_block
block.save()
prev_block.height = block.height - 1
prev_block.next_block = block
prev_block.save()
