Python BlockChain

Author: alisx

taiyangxue/README.md

@@ -16,7 +16,9 @@
 - [python39](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/python39) : 你在享受十一长假时，Python 已悄悄地变了
 - [matrix](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/matrix) : Python 世界的黑客帝国
 - [why](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/why) : 练那么多，为啥还不会编程
-- [rate](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/rate-of-return) : 练那么多，为啥还不会编程
+- [rate](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/rate-of-return) : 做时间的朋友，必须知道收益咋算
+- [blockchain](https://github.com/JustDoPython/python-examples/tree/master/taiyangxue/blockchain) : 比特币涨疯了，区块链是什么鬼？
+
 ---
 
 从小白到工程师的学习之路

taiyangxue/blockchain/main.py

@@ -0,0 +1,41 @@
+import hashlib as hasher
+import datetime as date
+
+class Block:
+    def __init__(self, index, timestamp, data, previous_hash):
+        self.index = index
+        self.timestamp = timestamp
+        self.data = data
+        self.previous_hash = previous_hash
+        self.hash = self.hash_block()
+
+    def hash_block(self):
+        sha = hasher.sha256()
+        sha.update((str(self.index) + str(self.timestamp) + str(self.data) + str(self.previous_hash)).encode("utf-8"))
+        return sha.hexdigest()
+
+def create_genesis_block():
+    # 手工创建第一个区块，其索引为 0，且随意取给紧前特征值 '0'
+    return Block(0, date.datetime.now(), "Genesis Block", "0")
+
+def next_block(last_block):
+    this_index = last_block.index + 1
+    this_timestamp = date.datetime.now()
+    this_data = "Hey! I'm block " + str(this_index)
+    this_hash = last_block.hash
+    return Block(this_index, this_timestamp, this_data, this_hash)
+
+# 创建一个区块链，并将第一个区块加入
+blockchain = [create_genesis_block()]
+
+# 设置产生区块的个数
+num_of_blocks_to_add = 20
+
+# 产生区块并加入区块链
+for i in range(0, num_of_blocks_to_add):
+    previous_block = blockchain[-1]
+    block_to_add = next_block(previous_block)
+    blockchain.append(block_to_add)
+    # 发布当前区块的信息
+    print("Block #{} has been added to the blockchain!".format(block_to_add.index))
+    print("Hash: {}\n".format(block_to_add.hash))