python区块链基本原型简版实现示例

class Block(object):
    """A Block
    Attributes:
        _magic_no (int): Magic number
        _block_header (Block): Header of the previous Block.
        _transactions (Transaction): transactions of the current Block.
    """
    MAGIC_NO = 0xBCBCBCBC
    def __init__(self, block_header, transactions):
        self._magic_no = self.MAGIC_NO
        self._block_header = block_header
        self._transactions = transactions

class BlockHeader(object):
    """ A BlockHeader
    Attributes:
        timestamp (str): Creation timestamp of Block
        prev_block_hash (str): Hash of the previous Block.
        hash (str): Hash of the current Block.
        hash_merkle_root(str): Hash of the merkle_root.
        height (int): Height of Block
        nonce (int): A 32 bit arbitrary random number that is typically used once.
    """
    def __init__(self, hash_merkle_root, height, pre_block_hash=''):
        self.timestamp = str(time.time())
        self.prev_block_hash = pre_block_hash
        self.hash = None
        self.hash_merkle_root = hash_merkle_root
        self.height = height
        self.nonce = None

    def set_hash(self):
        """
        Set hash of the header
        """
        data_list = [str(self.timestamp),
                     str(self.prev_block_hash),
                     str(self.hash_merkle_root),
                     str(self.height),
                     str(self.nonce)]
        data = ''.join(data_list)
        self.hash = sum256_hex(data)

class BlockChain(object):
    def __init__(self):
        self.blocks = []

    def add_block(self, transactions):
        """
        add a block to block_chain
        """
        last_block = self.blocks[-1]
        prev_hash = last_block.get_header_hash()
        height = len(self.blocks)
        block_header = BlockHeader('', height, prev_hash)
        block = Block(block_header, transactions)
        block.set_header_hash()
        self.blocks.append(block)

    # class BlockChain
    def new_genesis_block(self):
        if not self.blocks:
            genesis_block = Block.new_genesis_block('genesis_block')
            genesis_block.set_header_hash()
            self.blocks.append(genesis_block)
    # class Block
    @classmethod
    def new_genesis_block(cls, coin_base_tx):
        block_header = BlockHeader.new_genesis_block_header()
        return cls(block_header, coin_base_tx)
    # class BlockHeader
    @classmethod
    def new_genesis_block_header(cls):
        """
        NewGenesisBlock creates and returns genesis Block
        """
        return cls('', 0, '')

    # class BlockChain
    def __getitem__(self, index):
        if index < len(self.blocks):
            return self.blocks[index]
        else:
            raise IndexError('Index is out of range')

def main():
    bc = BlockChain()
    bc.new_genesis_block()
    bc.add_block('Send 1 BTC to B')
    bc.add_block('Send 2 BTC to B')
    for block in bc:
        print(block)
if __name__ == "__main__":
    main()

Block(_block_header=BlockHeader(timestamp='1548150457.22', hash_merkle_root='', prev_block_hash='', hash='f91f638a9a2b4caf241112d3bc92c9168cc9d52207a5580b3a549ed5343e2ed3', nonce=None, height=0))
Block(_block_header=BlockHeader(timestamp='1548150457.22', hash_merkle_root='', prev_block_hash='f91f638a9a2b4caf241112d3bc92c9168cc9d52207a5580b3a549ed5343e2ed3', hash='d21570e36f0c6f75c112d98416ca4ffae14e5cf02492bea5a7f8c398c1d458ca', nonce=None, height=1))
Block(_block_header=BlockHeader(timestamp='1548150457.22', hash_merkle_root='', prev_block_hash='d21570e36f0c6f75c112d98416ca4ffae14e5cf02492bea5a7f8c398c1d458ca', hash='9c78f38ec78a0d492a27e69ab04a3e0ba07d70d31a1ef96d581e8198d9781bc0', nonce=None, height=2))