feat: btc add psbtHexString func.

core/btc/account_test.go

@@ -351,6 +351,10 @@ func TestAccount_SignPsbt(t *testing.T) {
  txn, err := acc.SignPsbt(psbtHex)
  require.NoError(t, err)
  require.True(t, txn.Packet.IsComplete())
+
+ res, err := txn.PsbtHexString()
+ require.NoError(t, err)
+ t.Log("signed result: ", res.Value)
 }
 
 func TestChain_PushPsbt(t *testing.T) {

core/btc/transaction_psbt.go

@@ -1,6 +1,9 @@
 package btc
 
 import (
+ "bytes"
+ "encoding/hex"
+
  "github.com/btcsuite/btcd/btcutil/psbt"
  "github.com/coming-chat/wallet-SDK/core/base"
 )
@@ -44,6 +47,19 @@ func (t *SignedPsbtTransaction) HexString() (res *base.OptionalString, err error
  return nil, base.ErrUnsupportedFunction
 }
 
+func (t *SignedPsbtTransaction) PsbtHexString() (*base.OptionalString, error) {
+ packet := t.Packet
+ if err := EnsurePsbtFinalize(&packet); err != nil {
+ return nil, err
+ }
+ var buff bytes.Buffer
+ if err := packet.Serialize(&buff); err != nil {
+ return nil, err
+ }
+ hexString := hex.EncodeToString(buff.Bytes())
+ return &base.OptionalString{Value: hexString}, nil
+}
+
 func (t *SignedPsbtTransaction) PublishWithChain(c *Chain) (hashs *base.OptionalString, err error) {
  defer base.CatchPanicAndMapToBasicError(&err)