lwkwallet: implement SetLabel method

implement SetLabel method to call walletSetTxMemo
for setting transaction memos.

lwk/client.go

@@ -327,3 +327,20 @@ func (l *lwkclient) version(ctx context.Context) (*versionResponse, error) {
 	}
 	return &resp, nil
 }
+
+type WalletSetTxMemoRequest struct {
+	Memo       string `json:"memo"`
+	WalletName string `json:"name"`
+	Txid       string `json:"txid"`
+}
+
+func (r *WalletSetTxMemoRequest) Name() string {
+	return "wallet_set_tx_memo"
+}
+
+type WalletSetTxMemoResponse struct {
+}
+
+func (l *lwkclient) walletSetTxMemo(ctx context.Context, req *WalletSetTxMemoRequest) error {
+	return l.request(ctx, req, &WalletSetTxMemoResponse{})
+}

lwk/lwkwallet.go

@@ -278,8 +278,13 @@ func (r *LWKRpcWallet) GetFee(txSizeBytes int64) (Satoshi, error) {
 }
 
 func (r *LWKRpcWallet) SetLabel(txID, address, label string) error {
-	// TODO: call set label
-	return nil
+	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
+	defer cancel()
+	return r.lwkClient.walletSetTxMemo(ctx, &WalletSetTxMemoRequest{
+		WalletName: r.c.GetWalletName(),
+		Txid:       txID,
+		Memo:       label,
+	})
 }
 
 func (r *LWKRpcWallet) Ping() (bool, error) {