You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
97 lines
1.9 KiB
97 lines
1.9 KiB
package blockchain
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/sha256"
|
|
"encoding/gob"
|
|
"encoding/hex"
|
|
"fmt"
|
|
"log"
|
|
)
|
|
|
|
// Transaction represents a Bitcoin transaction
|
|
type Transaction struct {
|
|
ID []byte
|
|
TxInput []TXInput
|
|
TxOutput []TXOutput
|
|
}
|
|
|
|
// TXOutput is the struct of transaction output in a transaction.
|
|
type TXOutput struct {
|
|
Value int
|
|
Address string
|
|
}
|
|
|
|
// TXInput is the struct of transaction input in a transaction.
|
|
type TXInput struct {
|
|
TxID []byte
|
|
TxOutputIndex int
|
|
Address string
|
|
}
|
|
|
|
// DefaultCoinbaseValue is the default value of coinbase transaction.
|
|
const DefaultCoinbaseValue = 1000
|
|
|
|
// SetID sets ID of a transaction
|
|
func (tx *Transaction) SetID() {
|
|
var encoded bytes.Buffer
|
|
var hash [32]byte
|
|
|
|
enc := gob.NewEncoder(&encoded)
|
|
err := enc.Encode(tx)
|
|
if err != nil {
|
|
log.Panic(err)
|
|
}
|
|
hash = sha256.Sum256(encoded.Bytes())
|
|
tx.ID = hash[:]
|
|
}
|
|
|
|
// NewCoinbaseTX creates a new coinbase transaction
|
|
func NewCoinbaseTX(to, data string) *Transaction {
|
|
if data == "" {
|
|
data = fmt.Sprintf("Reward to '%s'", to)
|
|
}
|
|
|
|
txin := TXInput{[]byte{}, -1, data}
|
|
txout := TXOutput{DefaultCoinbaseValue, to}
|
|
tx := Transaction{nil, []TXInput{txin}, []TXOutput{txout}}
|
|
tx.SetID()
|
|
|
|
return &tx
|
|
}
|
|
|
|
// NewUTXOTransaction creates a new transaction
|
|
func NewUTXOTransaction(from, to string, amount int, bc *Blockchain) *Transaction {
|
|
var inputs []TXInput
|
|
var outputs []TXOutput
|
|
|
|
acc, validOutputs := bc.FindSpendableOutputs(from, amount)
|
|
|
|
if acc < amount {
|
|
return nil
|
|
}
|
|
|
|
// Build a list of inputs
|
|
for txid, outs := range validOutputs {
|
|
txID, err := hex.DecodeString(txid)
|
|
if err != nil {
|
|
return nil
|
|
}
|
|
|
|
for _, out := range outs {
|
|
input := TXInput{txID, out, from}
|
|
inputs = append(inputs, input)
|
|
}
|
|
}
|
|
|
|
// Build a list of outputs
|
|
outputs = append(outputs, TXOutput{amount, to})
|
|
if acc > amount {
|
|
outputs = append(outputs, TXOutput{acc - amount, from}) // a change
|
|
}
|
|
|
|
tx := Transaction{nil, inputs, outputs}
|
|
tx.SetID()
|
|
|
|
return &tx
|
|
}
|
|
|