极客教程Python区块链 添加区块
每个矿工将从先前创建的交易池中提取交易。为了跟踪已经开采的信息数量，我们必须创建一个全局变量–
last_transaction_index = 0
我们现在将有我们的第一个矿工向区块链添加一个区块。
添加第一个区块
为了添加一个新的区块，我们首先创建一个 Block 类的实例。
block = Block()
我们从队列中挑选出前3个交易 —
for i in range(3):
temp_transaction = transactions[last_transaction_index]
# validate transaction
在将交易添加到区块之前，矿工将验证交易的有效性。交易的有效性是通过测试发件人提供的哈希值与矿工用发件人的公钥生成的哈希值是否相等来验证的。此外，矿工将验证发件人是否有足够的余额来支付当前的交易。
为简洁起见，我们没有将这一功能纳入教程。在交易被验证后，我们将其添加到 区块 实例中的 verified_transactions 列表。
block.verified_transactions.append (temp_transaction)
我们增加最后一个交易的索引，这样下一个矿工就会在队列中拾取后续交易。
last_transaction_index += 1
我们正好给区块添加三个事务。一旦完成这些，我们将初始化 区块 类的其余实例变量。我们首先添加最后一个区块的哈希值。
block.previous_block_hash = last_block_hash
接下来，我们在难度为2的区块中开采。
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散列，并在其上创建一个摘要。
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。
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 = digest
添加更多区块
我们现在将向我们的区块链添加两个区块。添加下两个区块的代码如下所示
# 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
当你把这两个区块相加时，你也会看到找到Nonce的迭代次数。在这一点上，我们的区块链完全由4个区块组成，包括创世区块。
Dump整个区块链
您可以使用下面的语句验证整个区块链的内容 −
dump_blockchain(TPCoins)
你会看到与下图类似的输出结果 —
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
-----
--------------
=====================================