relayer/txm/bcs_util.go: support base64 encoded addresses (#140)

* relayer/txm/bcs_util.go: support base64 encoded addresses

* Fix return stmt and add test

---------

Co-authored-by: Friedemann Fürst <59653747+friedemannf@users.noreply.github.com>

Author: cfal

relayer/txm/bcs_util.go

@@ -1,6 +1,7 @@
 package txm
 
 import (
+	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -288,13 +289,21 @@ func serializeArg(argVal any, argType aptos.TypeTag, serializer *bcs.Serializer)
 			return nil
 		}
 		if v, ok := argVal.(string); ok {
-			address := &aptos.AccountAddress{}
-			err := address.ParseStringRelaxed(v)
-			if err != nil {
-				return err
+			// first, check if it's base64
+			decoded, err := base64.StdEncoding.DecodeString(v)
+			if err == nil && len(decoded) == 32 {
+				address := aptos.AccountAddress(decoded)
+				address.MarshalBCS(serializer)
+				return nil
+			} else {
+				address := &aptos.AccountAddress{}
+				err := address.ParseStringRelaxed(v)
+				if err != nil {
+					return err
+				}
+				address.MarshalBCS(serializer)
+				return nil
 			}
-			address.MarshalBCS(serializer)
-			return nil
 		}
 	case aptos.TypeTagVector:
 		itemType := argType.Value.(*aptos.VectorTag).TypeParam

relayer/txm/bcs_util_test.go

@@ -1,13 +1,48 @@
 package txm
 
 import (
+	"encoding/json"
 	"math/big"
 	"testing"
 
 	"github.com/aptos-labs/aptos-go-sdk"
+	"github.com/aptos-labs/aptos-go-sdk/bcs"
 	"github.com/stretchr/testify/require"
 )
 
+func TestCreateBcsValue(t *testing.T) {
+	t.Parallel()
+	t.Run("", func(t *testing.T) {
+		address := &aptos.AccountAddress{}
+		_ = address.ParseStringRelaxed("0x3b17dad1bdd88f337712cc2f6187bb741d56da467320373fd9198262cc93de76")
+		stringAddress := address.StringLong()
+		byteAddress, err := bcs.Serialize(address)
+		require.NoError(t, err)
+		typeTag, err := CreateTypeTag("address")
+		require.NoError(t, err)
+
+		// Test serializing a hex string value
+		serialized, err := CreateBcsValue(typeTag, stringAddress)
+		require.NoError(t, err)
+		require.Equal(t, byteAddress, serialized)
+
+		// Test serializing a base64 string
+		// When marshalling using JSON, the bytearray will be serialized as a base64 string,
+		// unmarshalling this string into an any will result in it being treated as a string, not a bytearray.
+		// CreateBcsValue is supposed to account for this by first testing if the value can be decoded using base64
+		marshaled, err := json.Marshal(struct {
+			Address []byte `json:"address"`
+		}{Address: byteAddress})
+		require.NoError(t, err)
+		result := make(map[string]interface{})
+		err = json.Unmarshal(marshaled, &result)
+		require.NoError(t, err)
+		serialized, err = CreateBcsValue(typeTag, result["address"].(string))
+		require.NoError(t, err)
+		require.Equal(t, byteAddress, serialized)
+	})
+}
+
 func TestGetBcsValues(t *testing.T) {
 	t.Parallel()
 	t.Run("uint32,uint64", func(t *testing.T) {