區(qū)塊鏈技術(shù)與應(yīng)用 第三章：分布式賬本

22v區(qū)塊鏈(Blockchain)本質(zhì)上是一個數(shù)據(jù)庫33…44……66……88融賬本基礎(chǔ)v交易(Transaction)v在區(qū)塊鏈賬本系統(tǒng)中，一條記錄(Item)通常為一條交易 99融賬本基礎(chǔ)v賬本(Ledger)v在區(qū)塊鏈賬本系統(tǒng)中，一個賬本(Ledger)即為一個區(qū)塊鏈 v區(qū)塊(Block)相當(dāng)于為賬本的分頁(Page)布式賬本特點v又稱共享賬本(SharedLedger)、分散式賬本技術(shù)(Distributed布式賬本特點布式賬本特點布式賬本特點v成本低(Cheap)v可信度高(Trustworthy)v匿名(Anonymous)/wp-content/uploads/2020/04/Python-Cheat-Sheet.pdfhttps://perso.limsi.fr/pointal/_media/python:cours:mementopython3-english.pdfimporthashlibfromwrenchbox.objectimportDict2StrSafeclassBase(Dict2StrSafe):defhash(self):returnhashlib.sha1(str(self.__dict__).encode()).hexdigest()/3/library/hashlib.importhashlibfromwrenchbox.objectimportDict2StrSafeclassBase(Dict2StrSafe):defhash(self):returnhashlib.sha1(str(self.__dict__).encode()).hexdigest()ox/object.pyclassA:def__init__(self):self.x=1classB:def__init__(self):self.a=A()b=B()print(b)fromwrenchbox.objectimportDict2StrSafeclassA1(Dict2StrSafe):def__init__(self):self.x=1classB1(Dict2StrSafe):def__init__(self):self.a=A1()b=B1()print(b)importhashlibfromwrenchbox.objectimportDict2StrSafeclassBase(Dict2StrSafe):defhash(self):returnhashlib.sha1(str(self.__dict__).encode()).hexdigest()fromdatetimeimportdatetimefromuuidimportUUIDfrom.basicimportBaseclassTransaction(Base):def__init__(self,sender:str,receiver:str,amount:int,t:float=None,prev_hash:str=None):classTransaction(Base):def__init__(self,…):assertUUID(sender,version=4)assertUUID(receiver,version=4)self.sender=senderself.receiver=receiverself.t=tiftisnotNoneelsedatetime.now().timestamp()self.prev_hash=prev_hashfrom.basicimportBaseclassBlock(Base):def__init__(self,prev_hash:str=None):self.items=[]self.prev_hash=prev_hash…classBlock(Base):…defadd(self,item):item.prev_hash=self.items[-1].hash()iflen(self.items)elseNoneself.items.append(item)…classBlock(Base):…defvalidate(self):foriinrange(len(self.items)):asserti==0orself.items[i].prev_hash==self.items[i-1].hash()classBlockchain(Base):def__init__(self):self.blocks=[]defadd(self,block):block.prev_hash=self.blocks[-1].hash()iflen(self.blocks)elseNoneself.blocks.append(block)…classBlockchain(Base):…defvalidate(self):foriinrange(len(self.blocks)):asserti==0orself.blocks[i].prev_hash==self.blocks[i-1].hash()self.blocks[i].validate()賬本importjsonfromuuidimportuuid4fromfoxchain.blockchainimportBlockchain,Blockfromfoxchain.transactionimportTransactionchain=Blockchain()…賬本…chain=Blockchain()foriinrange(3):block=Block()forjinrange(10):transaction=Transaction(sender=str(uuid4()),receiver=str(uuid4()),t)block.add(transaction)chain.add(block)…賬本……print(json.dumps(json.loads(str(chain)),indent=4,sort_keys=True))print(chain.validate())…賬本……chain.blocks[0].i