File size: 1,873 Bytes
f9870f1 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 |
# -*- coding: utf-8 -*-
"""Class Blockchain
Automatically generated by Colab.
Original file is located at
https://colab.research.google.com/drive/1EWMY4elMMGzoscgstOWF8wkyv0-3yShT
"""
import hashlib
import time
class Block:
def __init__(self, index, previous_hash, timestamp, data, hash):
self.index = index
self.previous_hash = previous_hash
self.timestamp = timestamp
self.data = data
self.hash = hash
def calculate_hash(index, previous_hash, timestamp, data):
value = str(index) + str(previous_hash) + str(timestamp) + str(data)
return hashlib.sha256(value.encode('utf-8')).hexdigest()
def create_genesis_block():
return Block(0, "0", int(time.time()), "Genesis Block", Block.calculate_hash(0, "0", int(time.time()), "Genesis Block"))
class Blockchain:
def __init__(self):
self.chain = [create_genesis_block()]
def get_latest_block(self):
return self.chain[-1]
def add_block(self, new_block):
new_block.previous_hash = self.get_latest_block().hash
new_block.hash = Block.calculate_hash(new_block.index, new_block.previous_hash, new_block.timestamp, new_block.data)
def create_new_block(previous_block, data):
index = previous_block.index + 1
timestamp = int(time.time())
return Block(index, previous_block.hash, timestamp, data, Block.calculate_hash(index, previous_block.hash, timestamp, data))
blockchain = Blockchain()
new_block = create_new_block(blockchain.get_latest_block(), "First new block after genesis")
blockchain.add_block(new_block)
new_block = create_new_block(blockchain.get_latest_block(), "Second new block after genesis")
blockchain.add_block(new_block)
for block in blockchain.chain:
print(f"Index: {block.index}")
print(f"Previous Hash: {block.previous_hash}")
print(f"Timestamp: {block.timestamp}")
print(f"Data: {block.data}")
print(f"Hash: {block.hash}\n") |