json 序列化不了

Question

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148

# 一个区块的基本结构 # { #     "index": 0, #     "timestamp": "", #     "transactions" : [ #          { #            "sender": "", #             "recipient": "", #             "amount": 5 #          } #     ], #     "proof": "", #     "previous_hash": "" # }   import hashlib import json from time import time from uuid import uuid4   from flask import Flask, request from flask.json import jsonify     class Blockchain:       def __init__(self):         # 定义一个区块链         self.chain = []         # 定义一个交易信息         self.current_transactions = []         # 定义一个创世区块         self.new_block(proof=100, previous_hash=1)       # 新建一个区块     def new_block(self, proof, previous_hash=None):         block = {             'index': len(self.chain) + 1,             'timestamp': time(),             'transactions': self.current_transactions,             'proof': proof,             'previous_hash': previous_hash or self.hash(self.last_block)         }         self.current_transactions = []         self.chain.append(block)         return block       # 新建交易记录(交易的发送者，交易的接收者，交易的金额)     def new_transaction(self, sender, recipient, amount) -> int:         self.current_transactions.append(             {                 'sender': sender,                 'recipient': recipient,                 'amount': amount             }         )         return self.last_block['index'] + 1       # 计算区块的哈希值     @staticmethod     def hash(block):         block_string = json.dumps(block, sort_keys=True).encode()         return hashlib.sha256(block_string)       # 获取区块链里面最后一个块     @property     def last_block(self):         return self.chain[-1]       # 工作量证明     def proof_of_work(self, last_proof: int) -> int:         proof = 0         while self.valid_proof(last_proof, proof) is False:             proof += 1         print(proof)         return proof       # 挖矿动作     @staticmethod     def valid_proof(last_proof: int, proof: int) -> bool:         guess = f'{last_proof}{proof}'.encode()         guess_hash = hashlib.sha256(guess).hexdigest()         print(guess_hash)         return guess_hash[0:4] == "0000"     # 节点之间的通讯 app = Flask(__name__) blockchain = Blockchain() # 生成一个uuid给自己做交易名称 node_identifier = str(uuid4()).replace('-', '')     # 测试通讯 @app.route('/index', methods=['GET']) def index():     return 'Hello BlockChain'     # 接收交易信息请求 @app.route('/transactions/new', methods=['POST']) def new_transactions():     values = request.get_json()     required = ['sender', 'recipient', 'amount']     if values is None:         return 'Missing values', 400     if not all(k in values for k in required):         return 'Missing values', 400       index = blockchain.new_transaction(values['sender'], values['recipient'], values['amount'])     response = {         'message': f'Transaction will be added to block {index}'     }     return jsonify(response), 201     # 打包交易 -> 挖矿 @app.route('/mine', methods=['GET']) def mine():     last_block = blockchain.last_block     last_proof = last_block['proof']     # 挖矿，并添加工作量证明     proof = blockchain.proof_of_work(last_proof)     # 给自己一个交易信息     blockchain.new_transaction(sender='0', recipient=node_identifier, amount=1)     block = blockchain.new_block(proof, None)     response = {         'message': 'New Block Forged',         'block': block['index'],         'transactions': block['transactions'],         'proof': block['proof'],         'previous_hash': block['previous_hash']     }     return jsonify(response), 200     # 返回整个区块链信息 @app.route('/chain', methods=['GET']) def full_chain():     response = {         'chain': blockchain.chain,         'length': len(blockchain.chain)     }     return jsonify(response), 200     if __name__ == '__main__':     app.run(host='0.0.0.0', port=5000)

Answer 1

Tiny 2018-06-04 12:40:42

引入包错了： 应该是： from flask import Flask, jsonify, request

• 提问者 带娃儿先走 #1

  重新引入了包也是报这个异常，难道是Python版本问题吗，我是3.7版本