示例#1
0
 def add_block(self, block):
     """
     Add an already created Block when broadcasting Blocks from different peers.
     :param block: the Block that will be added.
     :return: if the addition was successfully.
     """
     transactions = [
         Transaction(
             transaction['sender'],
             transaction['recipient'],
             transaction['amount'],
             transaction['signature']) for transaction in block['transactions']
     ]
     proof_is_valid = Verification.valid_proof(transactions[:-1], block['previous_hash'], block['proof'])
     hashes_match = hash_util.hash_block(self.get_chain()[-1]) == block['previous_hash']
     if not proof_is_valid or not hashes_match:
         return False
     converted_block = Block(block['index'], block['previous_hash'], transactions, block['proof'],
                             block['timestamp'])
     self.__chain.append(converted_block)
     stored_transactions = self.__open_transactions[:]
     for incoming_transaction in block['transactions']:
         for open_transaction in stored_transactions:
             if open_transaction.sender == incoming_transaction['sender'] \
                     and open_transaction.recipient == incoming_transaction['recipient'] \
                     and open_transaction.amount == incoming_transaction['amount'] \
                     and open_transaction.signature == incoming_transaction['signature']:
                 try:
                     self.__open_transactions.remove(open_transaction)
                 except ValueError:
                     print('The transaction was already removed!')
     self.save_data()
     return True
 def add_block(self, block):
     transactions = [
         Transaction(tx['sender'], tx['recipient'], tx['signature'],
                     tx['amount']) for tx in block['transactions']
     ]
     proof_is_valid = Verification.valid_proof(transactions[:-1],
                                               block['previous_hash'],
                                               block['proof'])
     hashes_match = hash_block(self.chain[-1]) == block['previous_hash']
     if not proof_is_valid or not hashes_match:
         return False
     converted_block = Block(block['index'], block['previous_hash'],
                             transactions, block['proof'],
                             block['timestamp'])
     self.__chain.append(converted_block)
     stored_transactions = self.__open_transactions[:]
     for itx in block['transactions']:
         for opentx in stored_transactions:
             if opentx.sender == itx['sender'] and opentx.recipient == itx[
                     'recipient'] and opentx.amount == itx[
                         'amount'] and opentx.signature == itx['signature']:
                 try:
                     self.__open_transactions.remove(opentx)
                 except ValueError:
                     print('Item was already removed')
     self.save_data()
     return True
 def add_block(self, block):
     # Create a list of transaction objects with the content in the dictionary key of the block 'transaction'
     transactions = [
         Transaction(tx['sender'], tx['recipient'], tx['signature'],
                     tx['amount']) for tx in block['transactions']
     ]
     # call the valid_proof without the last transaction because is the MINING reward transaction
     proof_is_valid = Verification.valid_proof(transactions[:-1],
                                               block['previous_hash'],
                                               block['proof'])
     hashes_match = create_hash_block(
         self.get_blockchain()[-1]) == block['previous_hash']
     if not proof_is_valid or not hashes_match:
         return False
     converted_block = Block(block['index'], block['previous_hash'],
                             transactions, block['proof'],
                             block['timestamp'])
     self.__blockchain.append(converted_block)
     stored_transactions = self.__open_transactions[:]
     # show if the incoming transactions are part of the open transactions and remove it if it´s the case
     for itx in block['transactions']:
         for opentx in stored_transactions:
             if opentx.sender == itx['sender'] and opentx.recipient == itx[
                     'recipient'] and opentx.amount == itx[
                         'amount'] and opentx.signature == itx['signature']:
                 try:
                     self.__open_transactions.remove(opentx)
                 except ValueError:
                     print('Item was already removed')
     self.save_data()
     return True
示例#4
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 def proof_of_work(self):
     last_block = self.__chain[-1]
     last_hash = hash_block(last_block)
     proof = 0
     while not Verification.valid_proof(self.__open_transactions, last_hash,
                                        proof):
         proof += 1
     return proof
    def proof_of_work(self) -> int:
        last_hash = hash_block(self.__chain[-1])
        proof = 0
        print('Proof of work...')
        while not Verification.valid_proof(self.__open_transactions, last_hash,
                                           proof):
            proof += 1

        return proof
 def proof_of_work(self):
     # get the first list element from the right
     last_block = self.__blockchain[-1]
     last_hash = create_hash_block(last_block)
     proof = 0
     while not Verification.valid_proof(self.__open_transactions, last_hash,
                                        proof):
         proof += 1
     return proof
 def proof_of_work(self):
     """Generate a proof of work for the open transactions, the hash of the previous block and a random number (which is guessed until it fits)."""
     last_block = self.__chain[-1]
     last_hash = hash_block(last_block)
     proof = 0
     # Try different PoW numbers and return the first valid one
     while not Verification.valid_proof(self.__open_transactions, last_hash,
                                        proof):
         proof += 1
     return proof
示例#8
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 def proof_of_work(self):
     """
     Generates a proof of work for the open transactions, based on the last hashed block which is guessed until it fits.
     :return: a valid number for the proof of work.
     """
     last_block = self.__chain[-1]
     last_hash = hash_util.hash_block(last_block)
     proof = 0
     while not Verification.valid_proof(self.__open_transactions, last_hash, proof):
         proof += 1
     return proof
示例#9
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    def proof_of_work(self):
        """ Calculates proof of work for mining a new block """

        last_block = self.get_last_blockchain_value()
        last_hash = hash_block(last_block)

        proof = 0
        while not Verification.valid_proof(self.__open_transactions, last_hash,
                                           proof):
            proof += 1

        return proof
    def add_block(self, block):
        transactions = [
            Transaction(tx['sender'], tx['recipient'], tx['signature'],
                        tx['amount']) for tx in block['transactions']
        ]
        proof_is_valid = Verification.valid_proof(transactions[:-1],
                                                  block['previous_hash'],
                                                  block['proof'])
        hashes_match = hash_block(self.chain[-1]) == block['previous_hash']
        if not proof_is_valid or not hashes_match:
            return False

        self.__chain.append(
            Block(block['index'], block['previous_hash'], transactions,
                  block['proof'], block['timestamp']))
        self.save_data()
        return True
示例#11
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    def proof_of_work(self):
        """
        Function to find the valid proof of work that the proof validation condition

        Returns
        -------
            proof (integer): Proof of work which satisfies condition

        """
        logger.info('Finding proof of work')
        last_block = self.__chain[-1]
        last_hash = hash_block(last_block)
        proof = 0
        while not Verification.valid_proof(self.__open_transactions, last_hash,
                                           proof):
            proof += 1
        return proof