#!/usr/bin/env python
# -*- coding: utf-8 -*-
import hashlib
import time
import json
block = {
'block_id': 1,
'difficulty': '00000'
}
def proof_of_work(block):
start_time = time.time()
sha_block = hashlib.sha256(block).digest()
json_block = json.loads(block)
diffu = json_block['difficulty']
proof = 0
while True:
work = hashlib.sha256(sha_block + str(proof)).hexdigest()
if work.startswith(diffu):
finished_time = time.time()
done_time = finished_time - start_time
print '-------------------'
print 'Difficulty:', diffu
print 'Proof Number:', proof
print 'Time:', done_time
print '-------------------'
break
else:
proof += 1
return (block, proof)
def verify_work(data):
block, proof = data
sha_block = hashlib.sha256(block).digest()
json_block = json.loads(block)
work = hashlib.sha256(sha_block + str(proof)).hexdigest()
if work.startswith(str(json_block['difficulty'])):
return True # Accepted
else:
return False # Rejected
working = proof_of_work(json.dumps(block))
verified = verify_work(working)
if verified:
print 'Block has been accepted!'
else:
print 'Block has been rejected!'
