iteracion5 - Serialización

iteracion5.py

# Copyright 2020 Carlos Castro Martos
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
# THE SOFTWARE.

import pickle
import hashlib
import time
import random
import argparse

class Block:
    def __init__(self, height, timestamp, data, hash, previous_hash, txs):
        self.height = height
        self.timestamp = timestamp
        self.data = data
        self.hash = self.hash_block()
        self.previous_hash = previous_hash
        self.txs = txs    
    
    def serialize_blk(self):
        return pickle.dumps(self)

    def deserialize_blk(self):
        return pickle.loads(self)

    def hash_block(self):
        sha = hashlib.sha256()
        sha.update(self.serialize_blk())
        return sha.hexdigest()
    
    @staticmethod
    def save_disk(obj):
        with open('blks.dat','wb') as hdl:
            pickle.dump(obj, hdl)

    @staticmethod
    def load_disk():
        with open('blks.dat','rb') as hdl:
            return pickle.load(hdl)

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument('-write', action="store_true", dest="write")
    parser.add_argument('-read', action="store_true", dest="read")
    args = parser.parse_args()
    if (args.write):
        bc = list()
        for i in range(0,5):
            b = Block(i, time.time(), b"data", 0, 0,[])
            for j in range(0,3):
                n = random.randint(1, 10)
                tx = {"nonce":j, "from":"alicia", "to":"roberto", "amount":n, "asset":"ESM"}
                b.txs.append(tx)
            bc.append(b)
    
        Block.save_disk(bc)

    if (args.read):
        bc = Block.load_disk()
        for b in bc:
            print(b.height, b.timestamp, b.data)
            print(b.hash, b.previous_hash)
            for t in b.txs:
                print(t)