def test_is_valid_block_jumped_difficulty(last_block, block):
jumped_difficulty = 10
block.difficulty = jumped_difficulty
block.hash = f'{"0" * jumped_difficulty}111abc'
with pytest.raises(Exception,
match='The block difficulty must only adjust by 1.'):
Block.is_valid_block(last_block, block)
def test_mined_block_difficulty_limits_at_1():
last_block = Block(time.time_ns(), 'test_last_hash', 'test_hash',
'test_data', 1, 0)
time.sleep(MINE_RATE / SECONDS)
mined_block = Block.mine_block(last_block, 'bar')
assert mined_block.difficulty == 1
def test_mine_block():
last_block = Block.genesis_block()
data = 'test-data'
block = Block.mine_block(last_block, data)
assert isinstance(block, Block)
assert block.data == data
assert block.last_hash == last_block.hash
assert hex_to_binary(
block.hash)[0:block.difficulty] == '0' * block.difficulty
def mine_block(self, transactions):
"""
根据链上的最后一个区块的hash值，生成一个新的block
:param transactions:
:return:
"""
lash_hash = self.blocks.get("l").decode()
height = self.get_height()
b = Block()
new_block = b.new_block(transactions, lash_hash, height + 1)
return new_block
def test_create_bc():
bc = BlockChain()
# 创世区块
coinbase = new_coinbase_tx("7AgP8z7XYyZ2sdnVJ6HCiE5X2reJDf")
genesis_block = new_genesis_block(coinbase)
bc.add_block(genesis_block)
b = Block()
# 自定义几个block
for i in range(5):
transactions = [b'Node1', b"Node2", b"Node3", b"Node4"]
last_hash = bc.blocks.get("l").decode()
height = bc.get_height()
new_block = b.new_block(transactions, last_hash, height + 1)
bc.add_block(new_block)
def is_valid_chain(chain):
"""
Validate the incoming chain.
Enforce the following rules of the blockchain:
- the chain must start with the genesis block.
- blocks must be formatted correctly.
"""
if chain[0] != Block.genesis_block():
raise Exception('The genesis block must be valid.')
for i in range(1, len(chain)):
block = chain[i]
# Previous block:
last_block = chain[i - 1]
Block.is_valid_block(last_block, block)
Blockchain.is_valid_transaction_chain(chain)
def deserialize_jsonified_chain(jsonified_chain):
"""
Deserialize a list of serialized blocks into a Blockchain instance.
The result will contain a chain list of Block instances.
"""
blockchain = Blockchain()
blockchain.chain = list(
map(
lambda jsonified_block: Block.deserialize_jsonified_block(
jsonified_block), jsonified_chain))
return blockchain
def add_block(self, data):
if self.blocks.get('l'):
# there we should mark last block hash to create a new block.
# in the redis the l is the last block hash value key.
last_hash = self.blocks.get('l').decode()
b = Block()
new_block = b.new_block(data, last_hash)
pow = ProofOfWork(new_block, new_block["Nonce"])
if pow.validate():
# self.blocks.append(new_block)
self.blocks.set(new_block["Hash"], new_block)
self.blocks.set("l", new_block["Hash"])
else:
b = Block()
new_block = b.new_block(data)
pow = ProofOfWork(new_block, new_block["Nonce"])
if pow.validate():
# self.blocks.append(new_block)
self.blocks.set(new_block["Hash"], new_block)
self.blocks.set("l", new_block["Hash"])
def message(self, pubnub, message_object):
print(
f'\n-- Channel: {message_object.channel} | Message: {message_object.message}'
)
if message_object.channel == CHANNELS['BLOCK']:
block = Block.deserialize_jsonified_block(message_object.message)
potential_chain = self.blockchain.chain[:] #Making copy of existing chain
potential_chain.append(block)
try:
self.blockchain.replace_chain(potential_chain)
self.transaction_pool.clear_blockchain_transactions(
self.blockchain)
print('\n -- Successfully replaced the local chain.')
except Exception as e:
print(f'\n -- Did not replace chain: {e}')
elif message_object.channel == CHANNELS['TRANSACTION']:
transaction = Transaction.from_json(message_object.message)
self.transaction_pool.set_transaction(transaction)
print('\n -- Set the new transaction in the transaction pool.')
#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
This Document is Created by At 2018/7/9
"""
from consensus.proof_of_work import ProofOfWork
from core.blockchain.block import Block
if __name__ == '__main__':
b = Block()
genesis_block = b.new_block("Magic test", "")
pow = ProofOfWork(genesis_block)
pow.run()
def add_block():
b = Block()
b.new_block("Magic", "")
block = b.block
return json.dumps(block)
def add_block(self, data):
self.chain.append(Block.mine_block(self.chain[-1], data))
def test_genesis():
genesis = Block.genesis_block()
assert isinstance(genesis, Block)
for key, value in GENESIS_DATA.items():
getattr(genesis, key) == value
def test_increased_difficulty_mined_block():
last_block = Block.mine_block(Block.genesis_block(), 'foo')
mined_block = Block.mine_block(last_block, 'bar')
assert mined_block.difficulty == last_block.difficulty + 1
def __init__(self):
self.chain = [Block.genesis_block()]
def test_decreased_difficulty_mined_block():
last_block = Block.mine_block(Block.genesis_block(), 'foo')
time.sleep(MINE_RATE / SECONDS)
mined_block = Block.mine_block(last_block, 'bar')
assert mined_block.difficulty == last_block.difficulty - 1
def test_is_valid_block_bad_block_hash(last_block, block):
block.hash = '000000000000000012abbbccccbc'
with pytest.raises(Exception, match='The block hash must be correct.'):
Block.is_valid_block(last_block, block)
def test_invalid_block_bad_proof_of_work(last_block, block):
block.hash = 'fff'
with pytest.raises(Exception,
match='The proof of requirement was not met.'):
Block.is_valid_block(last_block, block)
def last_block():
return Block.genesis_block()
def test_is_valid_block_bad_last_hash(last_block, block):
block.last_hash = 'evil_last_hash'
with pytest.raises(Exception, match='last_hash must be correct'):
Block.is_valid_block(last_block, block)
def test_is_valid_block(last_block, block):
Block.is_valid_block(last_block, block)
def block(last_block):
return Block.mine_block(last_block, 'test_data')