Python Blockchain 简明教程
Python Blockchain - Adding Blocks
每个矿工都会从先前创建的事务池中选取事务。为了追踪已挖掘的消息数量，我们必须创建一个全局变量 −
last_transaction_index = 0我们现在让第一个矿工向区块链添加一个区块。
Adding First Block
要添加新区块，我们首先创建一个 Block 类的实例。
block = Block()我们从队列中选取前 3 个事务 −
for i in range(3):
temp_transaction = transactions[last_transaction_index]
# validate transaction在将该事务添加到区块之前，矿工将验证事务的有效性。通过测试哈希与矿工利用发送方的公钥生成的哈希是否相等，来验证事务有效性。此外，矿工将验证发送方是否有足够的余额来支付当前事务。
为了简洁，我们没有在教程中包含此功能。验证事务后，我们会将其添加到 block 实例中的 verified_transactions 列表。
block.verified_transactions.append (temp_transaction)我们递增上一个事务索引，以便下一个矿工选择队列中的后续事务。
last_transaction_index += 1我们将恰好三个事务添加到区块。完成后，我们将初始化 Block 类的其余实例变量。我们首先添加上一个区块的哈希。
block.previous_block_hash = last_block_hash接下来，我们通过难度级别为 2 来挖掘区块。
block.Nonce = mine (block, 2)请注意， mine 函数的第一个参数是一个二进制对象。我们现在对整个区块进行哈希处理，并对它创建摘要。
digest = hash (block)最后，我们将创建的区块添加到区块链中，并重新初始化全局变量 last_block_hash ，以便在下一个区块中使用。
用于添加区块的整个代码如下所示 −
block = Block()
for i in range(3):
temp_transaction = transactions[last_transaction_index]
# validate transaction
# if valid
block.verified_transactions.append (temp_transaction)
last_transaction_index += 1
block.previous_block_hash = last_block_hash
block.Nonce = mine (block, 2)
digest = hash (block)
TPCoins.append (block)
last_block_hash = digestAdding More Blocks
我们现在将向我们的区块链添加两个区块。下面给出了添加下一个两个区块的代码 -
# Miner 2 adds a block
block = Block()
for i in range(3):
temp_transaction = transactions[last_transaction_index]
# validate transaction
# if valid
block.verified_transactions.append (temp_transaction)
last_transaction_index += 1
block.previous_block_hash = last_block_hash
block.Nonce = mine (block, 2)digest = hash (block)
TPCoins.append (block)last_block_hash = digest
# Miner 3 adds a block
block = Block()
for i in range(3):
temp_transaction = transactions[last_transaction_index]
#display_transaction (temp_transaction)
# validate transaction
# if valid
block.verified_transactions.append (temp_transaction)
last_transaction_index += 1
block.previous_block_hash = last_block_hash
block.Nonce = mine (block, 2)
digest = hash (block)
TPCoins.append (block)
last_block_hash = digest当你添加这两个区块时，你还会看到找到 Nonce 所需的迭代次数。在这一点上，我们的区块链包含 4 个区块，包括创世区块。
Dumping Entire Blockchain
你可以使用以下语句验证整个区块链的内容 -
dump_blockchain(TPCoins)你会看到类似于下面显示的输出 -
Number of blocks in the chain: 4
block # 0
sender: Genesis
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100ed272b52ccb539e2cd779
c6cc10ed1dfadf5d97c6ab6de90ed0372b2655626fb79f62d0e01081c163b0864cc68d426bbe943
8e8566303bb77414d4bfcaa3468ab7febac099294de10273a816f7047d4087b4bafa11f141544d4
8e2f10b842cab91faf33153900c7bf6c08c9e47a7df8aa7e60dc9e0798fb2ba3484bbdad2e44302
03010001
-----
value: 500.0
-----
time: 2019-01-14 16:18:02.042739
-----
--------------
=====================================
block # 1
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100bb064c99c492144a9f463
480273aba93ac1db1f0da3cb9f3c1f9d058cf499fd8e54d244da0a8dd6ddd329ec86794b04d773e
b4841c9f935ea4d9ccc2821c7a1082d23b6c928d59863407f52fa05d8b47e5157f8fe56c2ce3279
c657f9c6a80500073b0be8093f748aef667c03e64f04f84d311c4d866c12d79d3fc3034563dfb02
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100be93b516b28c6e674abe7
abdb11ce0fdf5bb728b75216b73f37a6432e4b402b3ad8139b8c0ba541a72c8add126b6e1a1308f
b98b727beb63c6060356bb177bb7d54b54dbe87aee7353d0a6baa9397704de625d1836d3f42c7ee
5683f6703259592cc24b09699376807f28fe0e00ff882974484d805f874260dfc2d1627473b9102
03010001
-----
value: 15.0
-----
time: 2019-01-14 16:18:01.859915
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100bb064c99c492144a9f463
480273aba93ac1db1f0da3cb9f3c1f9d058cf499fd8e54d244da0a8dd6ddd329ec86794b04d773e
b4841c9f935ea4d9ccc2821c7a1082d23b6c928d59863407f52fa05d8b47e5157f8fe56c2ce3279
c657f9c6a80500073b0be8093f748aef667c03e64f04f84d311c4d866c12d79d3fc3034563dfb02
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
value: 6.0
-----
time: 2019-01-14 16:18:01.860966
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100be93b516b28c6e674abe7
abdb11ce0fdf5bb728b75216b73f37a6432e4b402b3ad8139b8c0ba541a72c8add126b6e1a1308f
b98b727beb63c6060356bb177bb7d54b54dbe87aee7353d0a6baa9397704de625d1836d3f42c7ee
5683f6703259592cc24b09699376807f28fe0e00ff882974484d805f874260dfc2d1627473b9102
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100cba097c0854876f41338c
62598c658f545182cfa4acebce147aedf328181f9c4930f14498fd03c0af6b0cce25be99452a81d
f4fa30a53eddbb7bb7b203adf8764a0ccd9db6913a576d68d642d8fd47452590137869c25d9ff83
d68ebe6d616056a8425b85b52e69715b8b85ae807b84638d8f00e321b65e4c33acaf6469e18e302
03010001
-----
value: 2.0
-----
time: 2019-01-14 16:18:01.861958
-----
--------------
=====================================
block # 2
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100be93b516b28c6e674abe7
abdb11ce0fdf5bb728b75216b73f37a6432e4b402b3ad8139b8c0ba541a72c8add126b6e1a1308f
b98b727beb63c6060356bb177bb7d54b54dbe87aee7353d0a6baa9397704de625d1836d3f42c7ee
5683f6703259592cc24b09699376807f28fe0e00ff882974484d805f874260dfc2d1627473b9102
03010001
-----
value: 4.0
-----
time: 2019-01-14 16:18:01.862946
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100cba097c0854876f41338c
62598c658f545182cfa4acebce147aedf328181f9c4930f14498fd03c0af6b0cce25be99452a81d
f4fa30a53eddbb7bb7b203adf8764a0ccd9db6913a576d68d642d8fd47452590137869c25d9ff83
d68ebe6d616056a8425b85b52e69715b8b85ae807b84638d8f00e321b65e4c33acaf6469e18e302
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
value: 7.0
-----
time: 2019-01-14 16:18:01.863932
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100be93b516b28c6e674abe7
abdb11ce0fdf5bb728b75216b73f37a6432e4b402b3ad8139b8c0ba541a72c8add126b6e1a1308f
b98b727beb63c6060356bb177bb7d54b54dbe87aee7353d0a6baa9397704de625d1836d3f42c7ee
5683f6703259592cc24b09699376807f28fe0e00ff882974484d805f874260dfc2d1627473b9102
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
value: 3.0
-----
time: 2019-01-14 16:18:01.865099
-----
--------------
=====================================
block # 3
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100bb064c99c492144a9f463
480273aba93ac1db1f0da3cb9f3c1f9d058cf499fd8e54d244da0a8dd6ddd329ec86794b04d773e
b4841c9f935ea4d9ccc2821c7a1082d23b6c928d59863407f52fa05d8b47e5157f8fe56c2ce3279
c657f9c6a80500073b0be8093f748aef667c03e64f04f84d311c4d866c12d79d3fc3034563dfb02
03010001
-----
value: 8.0
-----
time: 2019-01-14 16:18:01.866219
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100a070c82b34ae143cbe59b
3a2afde7186e9d5bc274955d8112d87a00256a35369acc4d0edfe65e8f9dc93fbd9ee74b9e7ea12
334da38c8c9900e6ced1c4ce93f86e06611e656521a1eab561892b7db0961b4f212d1fd5b5e49ae
09cf8c603a068f9b723aa8a651032ff6f24e5de00387e4d062375799742a359b8f22c5362e56502
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100be93b516b28c6e674abe7
abdb11ce0fdf5bb728b75216b73f37a6432e4b402b3ad8139b8c0ba541a72c8add126b6e1a1308f
b98b727beb63c6060356bb177bb7d54b54dbe87aee7353d0a6baa9397704de625d1836d3f42c7ee
5683f6703259592cc24b09699376807f28fe0e00ff882974484d805f874260dfc2d1627473b9102
03010001
-----
value: 1.0
-----
time: 2019-01-14 16:18:01.867223
-----
--------------
sender:
30819f300d06092a864886f70d010101050003818d0030818902818100cba097c0854876f41338c
62598c658f545182cfa4acebce147aedf328181f9c4930f14498fd03c0af6b0cce25be99452a81d
f4fa30a53eddbb7bb7b203adf8764a0ccd9db6913a576d68d642d8fd47452590137869c25d9ff83
d68ebe6d616056a8425b85b52e69715b8b85ae807b84638d8f00e321b65e4c33acaf6469e18e302
03010001
-----
recipient:
30819f300d06092a864886f70d010101050003818d0030818902818100bb064c99c492144a9f463
480273aba93ac1db1f0da3cb9f3c1f9d058cf499fd8e54d244da0a8dd6ddd329ec86794b04d773e
b4841c9f935ea4d9ccc2821c7a1082d23b6c928d59863407f52fa05d8b47e5157f8fe56c2ce3279
c657f9c6a80500073b0be8093f748aef667c03e64f04f84d311c4d866c12d79d3fc3034563dfb02
03010001
-----
value: 5.0
-----
time: 2019-01-14 16:18:01.868241
-----
--------------
=====================================