update readme

README.md

@@ -51,6 +51,52 @@ func main() {
 }
 ```
 
+### Signing transaction
+
+```go
+package main
+
+import (
+	"log"
+	"math/big"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/miguelmota/go-ethereum-hdwallet"
+)
+
+func main() {
+	mnemonic := "tag volcano eight thank tide danger coast health above argue embrace heavy"
+	wallet, err := hdwallet.NewFromMnemonic(mnemonic)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	path := hdwallet.MustParseDerivationPath("m/44'/60'/0'/0/0")
+	account, err := wallet.Derive(path, true)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	nonce := uint64(0)
+	value := big.NewInt(1000000000000000000)
+	toAddress := common.HexToAddress("0x0")
+	gasLimit := uint64(21000)
+	gasPrice := big.NewInt(21000000000)
+	var data []byte
+
+	tx := types.NewTransaction(nonce, toAddress, value, gasLimit, gasPrice, data)
+
+	signedTx, err := wallet.SignTx(account, tx, nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	spew.Dump(signedTx)
+}
+```
+
 ## Test
 
 ```bash

example/sign.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"fmt"
 	"log"
 	"math/big"
 
@@ -19,13 +18,11 @@ func main() {
 	}
 
 	path := hdwallet.MustParseDerivationPath("m/44'/60'/0'/0/0")
-	account, err := wallet.Derive(path, false)
+	account, err := wallet.Derive(path, true)
 	if err != nil {
 		log.Fatal(err)
 	}
 
-	fmt.Println(account.Address.Hex()) // 0xC49926C4124cEe1cbA0Ea94Ea31a6c12318df947
-
 	nonce := uint64(0)
 	value := big.NewInt(1000000000000000000)
 	toAddress := common.HexToAddress("0x0")
@@ -37,7 +34,7 @@ func main() {
 
 	signedTx, err := wallet.SignTx(account, tx, nil)
 	if err != nil {
-		log.Fatal(signedTx)
+		log.Fatal(err)
 	}
 
 	spew.Dump(signedTx)

hdwallet.go

@@ -19,6 +19,16 @@ import (
 	"github.com/tyler-smith/go-bip39"
 )
 
+// DefaultRootDerivationPath is the root path to which custom derivation endpoints
+// are appended. As such, the first account will be at m/44'/60'/0'/0, the second
+// at m/44'/60'/0'/1, etc.
+var DefaultRootDerivationPath = accounts.DefaultRootDerivationPath
+
+// DefaultBaseDerivationPath is the base path from which custom derivation endpoints
+// are incremented. As such, the first account will be at m/44'/60'/0'/0, the second
+// at m/44'/60'/0'/1, etc
+var DefaultBaseDerivationPath = accounts.DefaultBaseDerivationPath
+
 // Wallet is the underlying wallet struct.
 type Wallet struct {
 	mnemonic  string