-
Notifications
You must be signed in to change notification settings - Fork 0
/
Account.js
97 lines (89 loc) · 2.8 KB
/
Account.js
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
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
const State = (exports.State = class State {
constructor(opts = {}) {
Object.assign(this, { wallets: {} }, opts);
}
hash() {
const keys = Object.keys(this.wallets).sort();
const head = JSON.stringify(keys);
const tail = JSON.stringify(keys.map((wl) => this.wallets[wl]));
return createHash("SHA256")
.update(head + tail)
.digest("hex");
}
with(mt) {
if (mt instanceof Transaction) {
const sender = this.wallets[mt.from] || { value: 0, nonce: 0 };
const target = this.wallets[mt.to] || { value: 0, nonce: 0 };
return new State({
...this,
wallets: {
...this.wallets,
[mt.from]: {
value: sender.value - mt.value,
nonce: sender.nonce + 1,
},
[mt.to]: { value: target.value + mt.value, nonce: target.nonce },
},
});
} else {
const miner = this.wallets[mt.miner] || { value: 0, nonce: 0 };
return new State({
...this,
wallets: {
...this.wallets,
[mt.miner]: { ...miner, value: miner.value + CONFIG.BLOCK_REWARD },
},
});
}
}
});
const Blockchain = (exports.Blockchain = class Blockchain {
constructor(opts = {}) {
Object.assign(
this,
{
state: new State(),
blocks: new Array(),
},
opts
);
}
static verifyTransaction(prev, state, tx) {
const sender = state.wallets[tx.from] || { value: 0 };
if (tx.value <= 0 || sender.value < tx.value) throw Error("Bad value.");
if (tx.nonce < 0 || sender.nonce > tx.nonce) throw Error("Bad nonce.");
if (prev && prev.nonce > tx.nonce) throw Error("Bad nonce order.");
if (!tx.test()) throw Error("Transaction is not signed properly.");
return state.with(tx);
}
static verifyBlock(prev, state, block) {
if (prev && block.parentHash !== prev.hash())
throw Error("Bad parentHash.");
if (prev && block.stateHash !== state.hash()) throw Error("Bad stateHash.");
if (!block.test()) throw Error("Block is not mined properly.");
return block.transactions.reduce((state, tx, index) => {
const prev = block.transactions[index - 1] || null;
return Blockchain.verifyTransaction(prev, state, tx);
}, state.with(block));
}
baln(address) {
if (!this.state.wallets[address]) return 0;
return this.state.wallets[address].value;
}
push(block) {
const prev = this.blocks[this.blocks.length - 1] || null;
this.state = Blockchain.verifyBlock(prev, this.state, block);
this.blocks.push(block);
}
mine(miner, transactions = []) {
const prev = this.blocks[this.blocks.length - 1] || null;
this.push(
new Block({
parentHash: prev && prev.hash(),
stateHash: this.state.hash(),
transactions,
miner,
}).mine()
);
}
});