Python实现简单的区块链

#imports the Block class from block.py from block import Block class Blockchain: def __init__(self): self.chain = [] self.all_transactions = [] self.genesis_block() def genesis_block(self): transactions = {} genesis_block = Block(transactions, "0") self.chain.append(genesis_block) return self.chain # prints contents of blockchain def print_blocks(self): for i in range(len(self.chain)): current_block = self.chain[i] print("Block {} {}".format(i, current_block)) current_block.print_contents() # add block to blockchain `chain` def add_block(self, transactions): previous_block_hash = self.chain[len(self.chain)-1].hash new_block = Block(transactions, previous_block_hash) # add proof of work proof = self.proof_of_work(new_block, 2) self.chain.append(new_block) return proof, new_block def validate_chain(self): for i in range(1, len(self.chain)): current = self.chain[i] previous = self.chain[i-1] if(current.hash != current.generate_hash()): print("当前区块的哈希码与其生成的哈希码不一致。") return False if(current.previous_hash != previous.generate_hash()): print("前一个区块生成的哈希码与后一个区块保存的上一区块哈希码不一致。") return False return True def proof_of_work(self,block, difficulty=2): proof = block.generate_hash() while proof[:difficulty] != '0'*difficulty: block.nonce += 1 proof = block.generate_hash() block.nonce = 0 return proof