Building-BlockChain-System-with-Python/mining.py at master · tkddus121/Building-BlockChain-System-with-Python · GitHub

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import base64
import time

from Crypto.Hash import keccak
from blkutils import get_difficulty, getLatestBlock, get_candidateblock
from block import Block
from key import Key
from transaction import Transaction
from utxo import UTXOset
from peer import Peer

# Class for Mining
########################################################################################################################
class Mining(object):

    # class variables
    _MiningFlag = False

    # Function for mining start
    ####################################################################################################################
    @classmethod
    def mineStart(cls):

        publicKey = Key._publicKey
        publicKey_ser = publicKey.serialize(compressed=False)

        if(cls._MiningFlag):
            return True

        cls.flagup()

        # Mining start
        ################################################################################################################
        while Mining._MiningFlag:

            target_diff = get_difficulty(Block._BlockHeight,
                                         getLatestBlock().difficulty)

            print('target difficulty :', target_diff)

            candidate_block = get_candidateblock()

            blockData = str(candidate_block.previous_block) + str(candidate_block.merkle_root) + str(target_diff)

            (targetNonce, time) = Mining.proofofwork(blockData, target_diff)

            if targetNonce == False:
                print('Failed to get golden nonce')
                continue
            else:
                keccak_hash = keccak.new(digest_bits=256)
                blockData = blockData + str(targetNonce)
                keccak_hash.update(blockData.encode('ascii'))

                candidate_block.block_hash = keccak_hash.hexdigest()
                candidate_block.difficulty = target_diff
                candidate_block.nonce = targetNonce
                candidate_block.timestamp = time

                # Add to RawBlock and _Blockchain
                ########################################################################################################
                Block.Insert_RawBlock(candidate_block.block_index,
                                      candidate_block.block_hash,
                                      candidate_block.previous_block,
                                      candidate_block.merkle_root,
                                      candidate_block.difficulty,
                                      candidate_block.timestamp,
                                      candidate_block.nonce,
                                      candidate_block.tx_set)

                Block.insert_blockchain(candidate_block.block_index,
                                        candidate_block.block_hash,
                                        candidate_block.previous_block,
                                        candidate_block.merkle_root,
                                        candidate_block.difficulty,
                                        candidate_block.timestamp,
                                        candidate_block.nonce,
                                        candidate_block.tx_set)

                ###Pikan
                print('successfully mined new block#' + str(Block._BlockHeight))

                candidate_block._broadcast_block()
                print('broadcast block#'+str(Block._BlockHeight))
                ###

            # Add to UTXOsets and myUTXOsets(for coinbase transaction only)
            ############################################################################################################
            coinbase = candidate_block.tx_set[0]
            coinbase_data = coinbase.vout[0]
            coinbase_tx_id = coinbase.tx_id

            UTXOset.Insert_UTXO(coinbase_tx_id,
                                0,
                                coinbase_data.lock,
                                coinbase_data.value)

            UTXOset.Insert_myUTXO(coinbase_tx_id,
                                  0,
                                  coinbase_data.lock,
                                  coinbase_data.value)

            # Delete from MemoryPool
            ############################################################################################################
            for tx in candidate_block.tx_set:
               Transaction.Pop_MemoryPool(base64.b64decode(tx.tx_id))


    # Proof of work
    ####################################################################################################################
    @classmethod
    def proofofwork(cls, blockData, targetValue):

        nonce = 0
        start = int(time.time())

        while(Mining._MiningFlag):
            keccak_hash = keccak.new(digest_bits=256)
            current_time = int(time.time())

            SumString = blockData + str(nonce) + str(current_time)
            elaped_time = int(current_time - start)

            keccak_hash.update(SumString.encode(('ascii')))

            if int('0x' + keccak_hash.hexdigest(), 0) < targetValue:
                print('target nonce :' + str(nonce))
                print('elapsed time: '+ str(elaped_time))

                return (nonce, current_time)

            nonce += 1

        return (False,0)

    # Flag value management
    ####################################################################################################################
    @classmethod
    def flagup(cls):
        cls._MiningFlag = True

    @classmethod
    def flagdown(cls):
        cls._MiningFlag = False

    @classmethod
    def miningflag(cls):
        return cls._MiningFlag

    #Method that caculates the vout's values of currenctBlock
    ####################################################################################################################
    def Calculate_curBlock(cls):
        pass
        #total_val=0
        #for tx in tx_set:
        #    tx_vout=tx.vout
        #    for i in range(0,len(tx_vout)):
        #        total_val+=tx_vout.value