def test_block_deserialization(self, b):
from bigchaindb.common.crypto import hash_data
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transaction = Transaction.create([b.me], [([b.me], 1)])
transaction.sign([b.me_private])
timestamp = gen_timestamp()
voters = ['Qaaa', 'Qbbb']
expected = Block([transaction], b.me, timestamp, voters)
block = {
'timestamp': timestamp,
'transactions': [transaction.to_dict()],
'node_pubkey': b.me,
'voters': voters,
}
block_body = {
'id': hash_data(serialize(block)),
'block': block,
'signature': None,
}
assert expected == Block.from_dict(block_body)
def test_get_votes_by_block_id(signed_create_tx, structurally_valid_vote):
from bigchaindb.common.crypto import generate_key_pair
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create and insert a block
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
# create and insert some votes
structurally_valid_vote['vote']['voting_for_block'] = block.id
conn.db.votes.insert_one(structurally_valid_vote)
# create a second vote under a different key
_, pk = generate_key_pair()
structurally_valid_vote['vote']['voting_for_block'] = block.id
structurally_valid_vote['node_pubkey'] = pk
structurally_valid_vote.pop('_id')
conn.db.votes.insert_one(structurally_valid_vote)
votes = list(query.get_votes_by_block_id(conn, block.id))
assert len(votes) == 2
assert votes[0]['vote']['voting_for_block'] == block.id
assert votes[1]['vote']['voting_for_block'] == block.id
def test_sign_block(self, b, alice):
from bigchaindb.common.crypto import PrivateKey, PublicKey
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transactions = [
Transaction.create([alice.public_key], [([alice.public_key], 1)])
]
timestamp = gen_timestamp()
voters = ['Qaaa', 'Qbbb']
expected_block = {
'timestamp': timestamp,
'transactions': [tx.to_dict() for tx in transactions],
'node_pubkey': alice.public_key,
'voters': voters,
}
expected_block_serialized = serialize(expected_block).encode()
expected = PrivateKey(
alice.private_key).sign(expected_block_serialized)
block = Block(transactions, alice.public_key, timestamp, voters)
block = block.sign(alice.private_key)
assert block.signature == expected.decode()
public_key = PublicKey(alice.public_key)
assert public_key.verify(expected_block_serialized, block.signature)
def test_from_db(self, b):
from bigchaindb.models import Block, Transaction
assets = [
{'msg': '1'},
{'msg': '2'},
{'msg': '3'},
]
txs = []
# create 3 assets
for asset in assets:
tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
txs.append(tx)
# create a `TRANSFER` transaction.
# the asset in `TRANSFER` transactions is not extracted
tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
asset_id=txs[0].id)
txs.append(tx)
# create the block
block = Block(txs)
# decouple assets
assets_from_block, block_dict = block.decouple_assets()
# write the assets and block separately
b.write_assets(assets_from_block)
b.write_block(block)
# check the reconstructed block is the same as the original block
block_from_db = Block.from_db(b, block_dict)
assert block == block_from_db
def test_get_last_voted_block_id(genesis_block, signed_create_tx, b):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
from bigchaindb.common.exceptions import CyclicBlockchainError
conn = connect()
# check that the last voted block is the genesis block
assert query.get_last_voted_block_id(conn, b.me) == genesis_block.id
# create and insert a new vote and block
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
vote = b.vote(block.id, genesis_block.id, True)
conn.db.votes.insert_one(vote)
assert query.get_last_voted_block_id(conn, b.me) == block.id
# force a bad chain
vote.pop('_id')
vote['vote']['voting_for_block'] = genesis_block.id
vote['vote']['previous_block'] = block.id
conn.db.votes.insert_one(vote)
with pytest.raises(CyclicBlockchainError):
query.get_last_voted_block_id(conn, b.me)
def test_filter_unspent_outputs(b, user_pk, user_sk):
out = [([user_pk], 1)]
tx1 = Transaction.create([user_pk], out * 3)
tx1.sign([user_sk])
# There are 3 inputs
inputs = tx1.to_inputs()
# Each spent individually
tx2 = Transaction.transfer([inputs[0]], out, tx1.id)
tx2.sign([user_sk])
tx3 = Transaction.transfer([inputs[1]], out, tx1.id)
tx3.sign([user_sk])
tx4 = Transaction.transfer([inputs[2]], out, tx1.id)
tx4.sign([user_sk])
# The CREATE and first TRANSFER are valid. tx2 produces a new unspent.
for tx in [tx1, tx2]:
block = Block([tx])
b.write_block(block)
b.write_vote(b.vote(block.id, '', True))
# The second TRANSFER is invalid. inputs[1] remains unspent.
block = Block([tx3])
b.write_block(block)
b.write_vote(b.vote(block.id, '', False))
# The third TRANSFER is undecided. It procuces a new unspent.
block = Block([tx4])
b.write_block(block)
outputs = b.fastquery.get_outputs_by_public_key(user_pk)
spents = b.fastquery.filter_unspent_outputs(outputs)
assert set(spents) == {inputs[0].fulfills, inputs[2].fulfills}
def get_block(self, block_id, include_status=False):
"""Get the block with the specified `block_id` (and optionally its status)
Returns the block corresponding to `block_id` or None if no match is
found.
Args:
block_id (str): transaction id of the transaction to get
include_status (bool): also return the status of the block
the return value is then a tuple: (block, status)
"""
# get block from database
block_dict = backend.query.get_block(self.connection, block_id)
# get the asset ids from the block
if block_dict:
asset_ids = Block.get_asset_ids(block_dict)
txn_ids = Block.get_txn_ids(block_dict)
# get the assets from the database
assets = self.get_assets(asset_ids)
# get the metadata from the database
metadata = self.get_metadata(txn_ids)
# add the assets to the block transactions
block_dict = Block.couple_assets(block_dict, assets)
# add the metadata to the block transactions
block_dict = Block.couple_metadata(block_dict, metadata)
status = None
if include_status:
if block_dict:
status = self.block_election_status(block_dict)
return block_dict, status
else:
return block_dict
def test_get_asset_ids(self, b):
from bigchaindb.models import Block, Transaction
assets = [
{'msg': '1'},
{'msg': '2'},
{'msg': '3'},
]
txs = []
# create 3 assets
for asset in assets:
tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
txs.append(tx)
# create a `TRANSFER` transaction.
# the asset in `TRANSFER` transactions is not extracted
tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
asset_id=txs[0].id)
txs.append(tx)
# create the block
block = Block(txs)
# decouple assets
assets_from_block, block_dict = block.decouple_assets()
# get the asset_ids and check that they are the same as the `CREATE`
# transactions
asset_ids = Block.get_asset_ids(block_dict)
assert asset_ids == [tx.id for tx in txs[:-1]]
def get_last_voted_block(self):
"""Returns the last block that this node voted on."""
try:
# get the latest value for the vote timestamp (over all votes)
max_timestamp = self.connection.run(
r.table('votes', read_mode=self.read_mode).filter(
r.row['node_pubkey'] == self.me).max(
r.row['vote']['timestamp']))['vote']['timestamp']
last_voted = list(
self.connection.run(
r.table('votes', read_mode=self.read_mode).filter(
r.row['vote']['timestamp'] == max_timestamp).filter(
r.row['node_pubkey'] == self.me)))
except r.ReqlNonExistenceError:
# return last vote if last vote exists else return Genesis block
res = self.connection.run(
r.table('bigchain', read_mode=self.read_mode).filter(
util.is_genesis_block))
block = list(res)[0]
return Block.from_dict(block)
# Now the fun starts. Since the resolution of timestamp is a second,
# we might have more than one vote per timestamp. If this is the case
# then we need to rebuild the chain for the blocks that have been retrieved
# to get the last one.
# Given a block_id, mapping returns the id of the block pointing at it.
mapping = {
v['vote']['previous_block']: v['vote']['voting_for_block']
for v in last_voted
}
# Since we follow the chain backwards, we can start from a random
# point of the chain and "move up" from it.
last_block_id = list(mapping.values())[0]
# We must be sure to break the infinite loop. This happens when:
# - the block we are currenty iterating is the one we are looking for.
# This will trigger a KeyError, breaking the loop
# - we are visiting again a node we already explored, hence there is
# a loop. This might happen if a vote points both `previous_block`
# and `voting_for_block` to the same `block_id`
explored = set()
while True:
try:
if last_block_id in explored:
raise exceptions.CyclicBlockchainError()
explored.add(last_block_id)
last_block_id = mapping[last_block_id]
except KeyError:
break
res = self.connection.run(
r.table('bigchain', read_mode=self.read_mode).get(last_block_id))
return Block.from_dict(res)
def test_compare_blocks(self, b):
from bigchaindb.models import Block, Transaction
transactions = [Transaction.create([b.me], [([b.me], 1)])]
assert Block() != 'invalid comparison'
assert Block(transactions) == Block(transactions)
def test_decouple_assets(self, b):
from bigchaindb.models import Block, Transaction
assets = [
{'msg': '1'},
{'msg': '2'},
{'msg': '3'},
]
txs = []
# create 3 assets
for asset in assets:
tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
txs.append(tx)
# create a `TRANSFER` transaction.
# the asset in `TRANSFER` transactions is not extracted
tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
asset_id=txs[0].id)
txs.append(tx)
# create the block
block = Block(txs)
# decouple assets
assets_from_block, block_dict = block.decouple_assets()
assert len(assets_from_block) == 3
for i in range(3):
assert assets_from_block[i]['data'] == assets[i]
assert assets_from_block[i]['id'] == txs[i].id
# check the `TRANSFER` transaction was not changed
assert block.transactions[3].to_dict() == \
block_dict['block']['transactions'][3]
def test_block_invalid_signature(self, b, alice):
from bigchaindb.common.crypto import hash_data
from bigchaindb.common.exceptions import InvalidSignature
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transaction = Transaction.create([alice.public_key],
[([alice.public_key], 1)])
transaction.sign([alice.private_key])
timestamp = gen_timestamp()
block = {
'timestamp': timestamp,
'transactions': [transaction.to_dict()],
'node_pubkey': alice.public_key,
}
block_body = {
'id': hash_data(serialize(block)),
'block': block,
'signature': 'an invalid signature',
}
with raises(InvalidSignature):
Block.from_dict(block_body).validate(b)
def get_block(self, block_id, include_status=False):
"""Get the block with the specified `block_id` (and optionally its status)
Returns the block corresponding to `block_id` or None if no match is
found.
Args:
block_id (str): transaction id of the transaction to get
include_status (bool): also return the status of the block
the return value is then a tuple: (block, status)
"""
# get block from database
block_dict = backend.query.get_block(self.connection, block_id)
# get the asset ids from the block
if block_dict:
asset_ids = Block.get_asset_ids(block_dict)
# get the assets from the database
assets = self.get_assets(asset_ids)
# add the assets to the block transactions
block_dict = Block.couple_assets(block_dict, assets)
status = None
if include_status:
if block_dict:
status = self.block_election_status(block_dict)
return block_dict, status
else:
return block_dict
def test_block_serialization(self, b, alice):
from bigchaindb.common.crypto import hash_data
from bigchaindb.common.utils import gen_timestamp, serialize
from bigchaindb.models import Block, Transaction
transactions = [
Transaction.create([alice.public_key], [([alice.public_key], 1)])
]
timestamp = gen_timestamp()
voters = ['Qaaa', 'Qbbb']
expected_block = {
'timestamp': timestamp,
'transactions': [tx.to_dict() for tx in transactions],
'node_pubkey': alice.public_key,
'voters': voters,
}
expected = {
'id': hash_data(serialize(expected_block)),
'block': expected_block,
'signature': None,
}
block = Block(transactions, alice.public_key, timestamp, voters)
assert block.to_dict() == expected
def test_get_spent_for_tx_with_multiple_inputs(carol):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block, Transaction
conn = connect()
tx_0 = Transaction.create(
[carol.public_key],
[([carol.public_key], 1), ([carol.public_key], 1),
([carol.public_key], 2)],
).sign([carol.private_key])
block = Block(transactions=[tx_0])
conn.db.bigchain.insert_one(block.to_dict())
spents = list(query.get_spent(conn, tx_0.id, 0))
assert not spents
tx_1 = Transaction.transfer(
tx_0.to_inputs()[2:3],
[([carol.public_key], 1), ([carol.public_key], 1)],
asset_id=tx_0.id,
).sign([carol.private_key])
block = Block(transactions=[tx_1])
conn.db.bigchain.insert_one(block.to_dict())
spents = list(query.get_spent(conn, tx_0.id, 0))
assert not spents
tx_2 = Transaction.transfer(
tx_0.to_inputs()[0:1] + tx_1.to_inputs()[1:2],
[([carol.public_key], 2)],
asset_id=tx_0.id,
).sign([carol.private_key])
block = Block(transactions=[tx_2])
conn.db.bigchain.insert_one(block.to_dict())
spents = list(query.get_spent(conn, tx_0.id, 1))
assert not spents
def test_count_blocks(signed_create_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create and insert some blocks
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
conn.db.bigchain.insert_one(block.to_dict())
assert query.count_blocks(conn) == 2
def test_write_block(signed_create_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create and write block
block = Block(transactions=[signed_create_tx])
query.write_block(conn, block.to_dict())
block_db = conn.db.bigchain.find_one({'id': block.id}, {'_id': False})
assert block_db == block.to_dict()
def blockdata(b, user_pk, user2_pk):
txs = [Transaction.create([user_pk], [([user2_pk], 1)]),
Transaction.create([user2_pk], [([user_pk], 1)]),
Transaction.create([user_pk], [([user_pk], 1), ([user2_pk], 1)])]
blocks = []
for i in range(3):
block = Block([txs[i]])
b.write_block(block)
blocks.append(block.to_dict())
b.write_vote(b.vote(blocks[1]['id'], '', True))
b.write_vote(b.vote(blocks[2]['id'], '', False))
return blocks, [b['id'] for b in blocks]
def test_get_block(signed_create_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create and insert block
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
block_db = query.get_block(conn, block.id)
assert block_db == block.to_dict()
def test_block_initialization(self, monkeypatch):
from bigchaindb.models import Block
monkeypatch.setattr('time.time', lambda: 1)
block = Block()
assert block.transactions == []
assert block.timestamp == '1'
assert block.node_pubkey is None
assert block.signature is None
with raises(TypeError):
Block('not a list or None')
def test_block_invalid_id_deserialization(self, b, alice):
from bigchaindb.common.exceptions import InvalidHash
from bigchaindb.models import Block
block = {
'id': 'an invalid id',
'block': {
'node_pubkey': alice.public_key,
}
}
with raises(InvalidHash):
Block.from_dict(block)
def test_get_owned_ids(signed_create_tx, user_pk):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create and insert a block
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
[(block_id, tx)] = list(query.get_owned_ids(conn, user_pk))
assert block_id == block.id
assert tx == signed_create_tx.to_dict()
def test_get_asset_by_id(create_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create asset and block
create_tx.asset = {'msg': 'aaa'}
block = Block(transactions=[create_tx])
conn.db.bigchain.insert_one(block.to_dict())
asset = list(query.get_asset_by_id(conn, create_tx.id))
assert len(asset) == 1
assert asset[0]['asset'] == create_tx.asset
def check_for_quorum(self, next_vote):
"""
Checks if block has enough invalid votes to make a decision
Args:
next_vote: The next vote.
"""
try:
block_id = next_vote['vote']['voting_for_block']
node = next_vote['node_pubkey']
except KeyError:
return
next_block = self.bigchain.get_block(block_id)
result = self.bigchain.block_election(next_block)
self.handle_block_events(result, block_id)
if result['status'] == self.bigchain.BLOCK_INVALID:
return Block.from_dict(next_block)
# Log the result
if result['status'] != self.bigchain.BLOCK_UNDECIDED:
msg = 'node:%s block:%s status:%s' % \
(node, block_id, result['status'])
# Extra data can be accessed via the log formatter.
# See logging.dictConfig.
logger_results.debug(msg,
extra={
'current_vote': next_vote,
'election_result': result,
})
def check_for_quorum(self, next_vote):
"""
Checks if block has enough invalid votes to make a decision
Args:
next_vote: The next vote.
"""
try:
block_id = next_vote['vote']['voting_for_block']
node = next_vote['node_pubkey']
except KeyError:
return
next_block = self.bigchain.get_block(block_id)
result = self.bigchain.block_election(next_block)
self.handle_block_events(result, block_id)
if result['status'] == self.bigchain.BLOCK_INVALID:
return Block.from_dict(next_block)
# Log the result
if result['status'] != self.bigchain.BLOCK_UNDECIDED:
msg = 'node:%s block:%s status:%s' % \
(node, block_id, result['status'])
# Extra data can be accessed via the log formatter.
# See logging.dictConfig.
logger_results.debug(msg, extra={
'current_vote': next_vote,
'election_result': result,
})
def test_get_block_status_from_transaction(create_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block
conn = connect()
# create a block
block = Block(transactions=[create_tx], voters=['aaa', 'bbb', 'ccc'])
# insert block
conn.db.bigchain.insert_one(block.to_dict())
block_db = list(
query.get_blocks_status_from_transaction(conn, create_tx.id))
assert len(block_db) == 1
block_db = block_db.pop()
assert block_db['id'] == block.id
assert block_db['block']['voters'] == block.voters
def test_get_transaction_from_block(user_pk):
from bigchaindb.backend import connect, query
from bigchaindb.models import Transaction, Block
conn = connect()
# create a block with 2 transactions
txs = [
Transaction.create([user_pk], [([user_pk], 1)]),
Transaction.create([user_pk], [([user_pk], 1)]),
]
block = Block(transactions=txs)
conn.db.bigchain.insert_one(block.to_dict())
tx_db = query.get_transaction_from_block(conn, txs[0].id, block.id)
assert tx_db == txs[0].to_dict()
assert query.get_transaction_from_block(conn, txs[0].id, 'aaa') is None
assert query.get_transaction_from_block(conn, 'aaa', block.id) is None
def test_couple_assets(self, b, alice):
from bigchaindb.models import Block, Transaction
assets = [
{
'msg': '1'
},
{
'msg': '2'
},
{
'msg': '3'
},
]
txs = []
# create 3 assets
for asset in assets:
tx = Transaction.create([alice.public_key],
[([alice.public_key], 1)],
asset=asset)
tx.sign([alice.private_key])
txs.append(tx)
# create a `TRANSFER` transaction.
# the asset in `TRANSFER` transactions is not extracted
tx = Transaction.transfer(txs[0].to_inputs(),
[([alice.public_key], 1)],
asset_id=txs[0].id)
tx.sign([alice.private_key])
txs.append(tx)
# create the block
block = Block(txs)
# decouple assets
assets_from_block, block_dict = block.decouple_assets()
# reconstruct the block
block_dict_reconstructed = Block.couple_assets(block_dict,
assets_from_block)
# check that the reconstructed block is the same as the original block
assert block == Block.from_dict(block_dict_reconstructed)
def test_get_last_voted_block_returns_genesis_if_no_votes_has_been_casted(
self, b):
from bigchaindb.models import Block
from bigchaindb.backend import query
genesis = query.get_genesis_block(b.connection)
genesis = Block.from_db(b, genesis)
gb = b.get_last_voted_block()
assert gb == genesis
assert b.validate_block(gb) == gb
def test_get_spending_transactions(user_pk):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block, Transaction
conn = connect()
out = [([user_pk], 1)]
tx1 = Transaction.create([user_pk], out * 3)
inputs = tx1.to_inputs()
tx2 = Transaction.transfer([inputs[0]], out, tx1.id)
tx3 = Transaction.transfer([inputs[1]], out, tx1.id)
tx4 = Transaction.transfer([inputs[2]], out, tx1.id)
block = Block([tx1, tx2, tx3, tx4])
conn.db.bigchain.insert_one(block.to_dict())
links = [inputs[0].fulfills.to_dict(), inputs[2].fulfills.to_dict()]
res = list(query.get_spending_transactions(conn, links))
# tx3 not a member because input 1 not asked for
assert res == [(block.id, tx2.to_dict()), (block.id, tx4.to_dict())]
def test_block_dupe_tx(self, b, alice):
from bigchaindb.models import Block, Transaction
from bigchaindb.common.exceptions import DuplicateTransaction
tx = Transaction.create([alice.public_key], [([alice.public_key], 1)])
block = Block([tx, tx], alice.public_key)
block.sign(alice.private_key)
b.store_block(block.to_dict())
with raises(DuplicateTransaction):
block.validate(b)
def test_get_txids_filtered(signed_create_tx, signed_transfer_tx):
from bigchaindb.backend import connect, query
from bigchaindb.models import Block, Transaction
conn = connect()
# create and insert two blocks, one for the create and one for the
# transfer transaction
block = Block(transactions=[signed_create_tx])
conn.db.bigchain.insert_one(block.to_dict())
block = Block(transactions=[signed_transfer_tx])
conn.db.bigchain.insert_one(block.to_dict())
asset_id = Transaction.get_asset_id([signed_create_tx, signed_transfer_tx])
# Test get by just asset id
txids = set(query.get_txids_filtered(conn, asset_id))
assert txids == {signed_create_tx.id, signed_transfer_tx.id}
# Test get by asset and CREATE
txids = set(query.get_txids_filtered(conn, asset_id, Transaction.CREATE))
assert txids == {signed_create_tx.id}
# Test get by asset and TRANSFER
txids = set(query.get_txids_filtered(conn, asset_id, Transaction.TRANSFER))
assert txids == {signed_transfer_tx.id}
def create_block(self, validated_transactions):
"""Creates a block given a list of `validated_transactions`.
Note that this method does not validate the transactions. Transactions
should be validated before calling create_block.
Args:
validated_transactions (list(Transaction)): list of validated
transactions.
Returns:
Block: created block.
"""
# Prevent the creation of empty blocks
if len(validated_transactions) == 0:
raise exceptions.OperationError('Empty block creation is not '
'allowed')
voters = self.nodes_except_me + [self.me]
block = Block(validated_transactions, self.me, gen_timestamp(), voters)
block = block.sign(self.me_private)
return block
def check_for_quorum(self, next_vote):
"""
Checks if block has enough invalid votes to make a decision
Args:
next_vote: The next vote.
"""
next_block = self.bigchain.get_block(
next_vote['vote']['voting_for_block'])
block_status = self.bigchain.block_election_status(next_block['id'],
next_block['block']['voters'])
if block_status == self.bigchain.BLOCK_INVALID:
return Block.from_dict(next_block)
def validate_block(self, block):
if not self.bigchain.has_previous_vote(block['id']):
try:
block = Block.from_dict(block)
except (exceptions.InvalidHash):
# XXX: if a block is invalid we should skip the `validate_tx`
# step, but since we are in a pipeline we cannot just jump to
# another function. Hackish solution: generate an invalid
# transaction and propagate it to the next steps of the
# pipeline.
return block['id'], [self.invalid_dummy_tx]
try:
block._validate_block(self.bigchain)
except exceptions.ValidationError:
# XXX: if a block is invalid we should skip the `validate_tx`
# step, but since we are in a pipeline we cannot just jump to
# another function. Hackish solution: generate an invalid
# transaction and propagate it to the next steps of the
# pipeline.
return block.id, [self.invalid_dummy_tx]
return block.id, block.transactions
def get_last_voted_block(self):
"""Returns the last block that this node voted on."""
return Block.from_dict(backend.query.get_last_voted_block(self.connection, self.me))
