def on_post(self, req, resp):
block_hash = None
if 'block_id' in req.media:
block = Block.query(self.session).filter(
Block.id == req.media.get('block_id')).first()
elif req.media.get('block_hash'):
block_hash = req.media.get('block_hash')
block = Block.query(
self.session).filter(Block.hash == block_hash).first()
else:
block = None
resp.status = falcon.HTTP_BAD_REQUEST
resp.media = {
'errors': ['Either block_hash or block_id should be supplied']
}
if block:
print('Sequencing #{} ...'.format(block.id))
harvester = PolkascanHarvesterService(self.session,
type_registry=TYPE_REGISTRY)
if block.id == 1:
# Add genesis block
parent_block = harvester.add_block(block.parent_hash)
block_total = BlockTotal.query(
self.session).filter_by(id=block.id).first()
parent_block = Block.query(
self.session).filter(Block.id == block.id - 1).first()
parent_block_total = BlockTotal.query(
self.session).filter_by(id=block.id - 1).first()
if block_total:
resp.status = falcon.HTTP_200
resp.media = {'result': 'already exists', 'blockId': block.id}
else:
if parent_block_total:
parent_block_total = parent_block_total.asdict()
if parent_block:
parent_block = parent_block.asdict()
harvester.sequence_block(block, parent_block,
parent_block_total)
self.session.commit()
resp.status = falcon.HTTP_201
resp.media = {
'result': 'added',
'parentHash': block.parent_hash
}
else:
resp.status = falcon.HTTP_404
resp.media = {'result': 'Block not found'}
def sequence_block_recursive(self,
parent_block_data,
parent_sequenced_block_data=None):
harvester = PolkascanHarvesterService(self.session,
type_registry=TYPE_REGISTRY)
harvester.metadata_store = self.metadata_store
for nr in range(0, 10):
if not parent_sequenced_block_data:
# No block ever sequenced, check if chain is at genesis state
block = Block.query(self.session).order_by('id').first()
if block.id == 1:
# Add genesis block
block = harvester.add_block(block.parent_hash)
if block.id != 0:
return {'error': 'Chain not at genesis'}
harvester.process_genesis(block)
block_id = 0
else:
block_id = parent_sequenced_block_data['id'] + 1
block = Block.query(self.session).get(block_id)
if block:
try:
sequenced_block = harvester.sequence_block(
block, parent_block_data, parent_sequenced_block_data)
self.session.commit()
parent_block_data = block.asdict()
parent_sequenced_block_data = sequenced_block.asdict()
if nr == 9 or not sequenced_block:
if sequenced_block:
if nr == 9:
sequence_block_recursive.delay(
parent_block_data, parent_sequenced_block_data)
return {'processedBlockId': block.id, 'amount': nr + 1}
except IntegrityError as e:
return {
'error': 'Sequencer already started',
'exception': str(e)
}
else:
return {'error': 'Block {} not found'.format(block_id)}
