utxo outidx, fix sign tx

README.md

@@ -19,6 +19,8 @@ func main() {
 	fmt.Printf("Private Key: %s\nBitcoin address: %s\n", privateKey, address)
 }
 ```
+If you just started learning about bitcoins and blockchain, you probably **don't have any testnet bitcoins**, wondering where I can get some.
+People on [bitcoin.stackexchange](https://bitcoin.stackexchange.com/questions/17690/is-there-any-where-to-get-free-testnet-bitcoins) provided a lot of links.    
 
 ## Sending transaction
 First we need to create a transaction then broadcast it to blockchain.  
@@ -59,7 +61,12 @@ func main() {
 **For testing purposes** I used `netchain.TestNet`. If you want to send real bitcoins to blockchain you need to specify BTC_API_KEY env var for blockcypher or you could pass your own txutil.CreateParams.Fetch function to txutil.Create.
 
 ---   
-You can send your bitcoins from multiple wallets by specifying `CreateParams.PrivateKeys`, an array of private keys.  
-If you specified only one destination address you can set `CreateParams.SendAll` to `true` to send all your bitcoins from your private key or keys.
-You can also send your bitcoins to multiple addresses by specifying `CreateParams.Destinations`.  
-For the full list of transaction parameters look inside `txutil.CreateParams`.
+#### More options
+`txutil.CreateParams`:
+
+| Field         | Type                 | Usage  |
+|:-------------:|:--------------------:|------- |
+| PrivateKeys  | []string              | send your bitcoins from multiple wallets |
+| Destinations | []txutil.Destination  | send your bitcoins to multiple addresses |
+| SendAll      | bool                  | send all your bitcoins from your private key or keys, but it only works if you specified just one destination |
+For the full list of the transaction parameters look inside `txutil.CreateParams`.

addressinfo/api.go

@@ -11,7 +11,7 @@ type UTXO struct {
 	TxID     string
 	Pbscript string
 	Balance  int64
-	TxOutIdx uint32
+	TxOutIdx int
 }
 
 type Fetch func(address string, net netchain.Net) (Address, error)

addressinfo/blockchain.go

@@ -45,7 +45,7 @@ func FetchFromBlockchain(address string, net netchain.Net) (Address, error) {
 			TxID:     output.TxID,
 			Pbscript: output.Script,
 			Balance:  output.Value,
-			TxOutIdx: uint32(output.TxOutputN),
+			TxOutIdx: output.TxOutputN,
 		})
 		balance += output.Value
 	}

addressinfo/blockcypher.go

@@ -17,7 +17,7 @@ func FetchFromBlockcypher(address string, net netchain.Net) (Address, error) {
 		for outputIdx, output := range tx.Outputs {
 			if len(output.Addresses) == 1 && output.Addresses[0] == address {
 				if output.SpentBy == "" {
-					utxos = append(utxos, UTXO{TxID: tx.Hash, Balance: output.Value.Int64(), Pbscript: output.Script, TxOutIdx: uint32(outputIdx)})
+					utxos = append(utxos, UTXO{TxID: tx.Hash, Balance: output.Value.Int64(), Pbscript: output.Script, TxOutIdx: outputIdx})
 				}
 			}
 		}

addressinfo/mock.go

@@ -1,13 +1,14 @@
 package addressinfo
 
 import (
+	"github.com/btcsuite/btcd/wire"
 	"github.com/glossd/btc/netchain"
 	mathrand "math/rand"
 )
 
 func FetchMock(address string, net netchain.Net) (Address, error) {
 	var utxoMock = UTXO{
-		TxID:     "5dcb1e3a6fcd02e9e216113deda9a914b2b2191a0bb42383817b737c4c3280e2",
+		TxID:     wire.NewMsgTx(wire.TxVersion).TxHash().String(),
 		Balance:  mathrand.Int63n(50000000) + 1000000,
 		Pbscript: "76a914fee7132bbe9201c4f1a0f846b5f714d9335e263088ac",
 		TxOutIdx: 1,

txutil/create.go

@@ -12,6 +12,7 @@ import (
 	"github.com/glossd/btc/netchain"
 	"github.com/glossd/btc/wallet"
 	"sort"
+	"strconv"
 )
 
 const defaultMinerFee = 5000
@@ -208,7 +209,7 @@ func addInputs(tx *wire.MsgTx, utxos []addressinfo.UTXO) error {
 		if err != nil {
 			return err
 		}
-		outPoint := wire.NewOutPoint(utxoHash, utxo.TxOutIdx)
+		outPoint := wire.NewOutPoint(utxoHash, uint32(utxo.TxOutIdx))
 		txIn := wire.NewTxIn(outPoint, nil, nil)
 		tx.AddTxIn(txIn)
 	}
@@ -301,7 +302,6 @@ func toPayAddress(address string, net netchain.Net) ([]byte, error) {
 }
 
 func signTx(tx *wire.MsgTx, addresses []address) error {
-
 	type utxoWithKey struct {
 		addressinfo.UTXO
 		wif *btcutil.WIF
@@ -318,12 +318,12 @@ func signTx(tx *wire.MsgTx, addresses []address) error {
 			if err != nil {
 				return fmt.Errorf("signing transaction failed, could compute hash utxo=%v", u)
 			}
-			utxosToSpendMap[h.String()] = utxoWithKey{UTXO: u, wif: wif}
+			utxosToSpendMap[h.String() + strconv.Itoa(u.TxOutIdx)] = utxoWithKey{UTXO: u, wif: wif}
 		}
 	}
 
 	for i, in := range tx.TxIn {
-		utxoOfIn := utxosToSpendMap[in.PreviousOutPoint.Hash.String()]
+		utxoOfIn := utxosToSpendMap[in.PreviousOutPoint.Hash.String() + strconv.Itoa(int(in.PreviousOutPoint.Index))]
 		sourcePkString, err := hex.DecodeString(utxoOfIn.Pbscript)
 		if err != nil {
 			return err

txutil/create_test.go

@@ -49,8 +49,8 @@ func TestCreate_SendAll(t *testing.T) {
 
 func TestCreate_MultiplePrivateKeys(t *testing.T) {
 	rawTx, err := Create(CreateParams{
-		PrivateKeys: []string{privateKey1, "cMvRbsVJKjRkZTV7tosWEYEu1x8tQcnLEbC64RiKwPeeEz29j8QZ"},
-		Destination: "mwRL1TpsRSFy5KXbxEd2KrHiD16VvbbAdj",
+		PrivateKeys: []string{privateKey1, privateKey2},
+		Destination: destination3,
 		SendAll: true,
 		Net: netchain.TestNet,
 	})