创建自己的区块链

import hashlib
import json
from time import time
from flask import Flask, jsonify, request

class Blockchain:
    def __init__(self):
        self.chain = []
        self.current_transactions = []

        # 创建创世区块
        self.new_block(previous_hash='1', proof=100)

    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.chain[-1]),
        }
        self.current_transactions = []
        self.chain.append(block)
        return block

    def new_transaction(self, sender, recipient, amount):
        self.current_transactions.append({
            'sender': sender,
            'recipient': recipient,
            'amount': amount,
        })
        return self.last_block['index'] + 1

    @staticmethod
    def hash(block):
        block_string = json.dumps(block, sort_keys=True).encode()
        return hashlib.sha256(block_string).hexdigest()

    @property
    def last_block(self):
        return self.chain[-1]

app = Flask(__name__)
blockchain = Blockchain()

@app.route('/mine', methods=['GET'])
def mine():
    # 模拟挖矿过程
    last_proof = blockchain.last_block['proof']
    proof = 0
    while not valid_proof(last_proof, proof):
        proof += 1
    blockchain.new_transaction(sender="0", recipient=node_identifier, amount=1)
    previous_hash = blockchain.hash(blockchain.last_block)
    block = blockchain.new_block(proof, previous_hash)
    response = {
        'message': "New Block Forged",
        'index': block['index'],
        'transactions': block['transactions'],
        'proof': block['proof'],
        'previous_hash': block['previous_hash'],
    }
    return jsonify(response), 200

def valid_proof(last_proof, proof):
    guess = f'{last_proof}{proof}'.encode()
    guess_hash = hashlib.sha256(guess).hexdigest()
    return guess_hash[:4] == "0000"

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)