feat: defer parsing localtxsubmission reject reason

Fixes #85

Author: agaffney

cmd/go-ouroboros-network/localtxsubmission.go

@@ -5,8 +5,8 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	ouroboros "github.com/cloudstruct/go-ouroboros-network"
 	"github.com/cloudstruct/go-cardano-ledger"
+	ouroboros "github.com/cloudstruct/go-ouroboros-network"
 	"github.com/cloudstruct/go-ouroboros-network/protocol/localtxsubmission"
 	"io/ioutil"
 	"os"
@@ -105,8 +105,8 @@ func localTxSubmissionAcceptTxHandler() error {
 	return nil
 }
 
-func localTxSubmissionRejectTxHandler(reason interface{}) error {
-	fmt.Printf("The transaction was rejected: %#v\n", reason)
+func localTxSubmissionRejectTxHandler(reasonCbor []byte) error {
+	fmt.Printf("The transaction was rejected (reason in hex-encoded CBOR): %#v\n", reasonCbor)
 	os.Exit(1)
 	return nil
 }

protocol/localtxsubmission/localtxsubmission.go

@@ -59,7 +59,7 @@ type CallbackConfig struct {
 // Callback function types
 type SubmitTxFunc func(interface{}) error
 type AcceptTxFunc func() error
-type RejectTxFunc func(interface{}) error
+type RejectTxFunc func([]byte) error
 type DoneFunc func() error
 
 func New(options protocol.ProtocolOptions) *LocalTxSubmission {
@@ -135,7 +135,7 @@ func (l *LocalTxSubmission) handleRejectTx(msgGeneric protocol.Message) error {
 	}
 	msg := msgGeneric.(*MsgRejectTx)
 	// Call the user callback function
-	return l.callbackConfig.RejectTxFunc(msg.Reason)
+	return l.callbackConfig.RejectTxFunc([]byte(msg.Reason))
 }
 
 func (l *LocalTxSubmission) handleDone() error {

protocol/localtxsubmission/messages.go

@@ -80,15 +80,18 @@ func NewMsgAcceptTx() *MsgAcceptTx {
 
 type MsgRejectTx struct {
 	protocol.MessageBase
-	Reason interface{}
+	// TODO: find a better way to handle this
+	// We use RawMessage here because the failure reason can often contain
+	// structures that we can't currently parse, such as maps with []uint8 keys
+	Reason cbor.RawMessage
 }
 
-func NewMsgRejectTx(reason interface{}) *MsgRejectTx {
+func NewMsgRejectTx(reasonCbor []byte) *MsgRejectTx {
 	m := &MsgRejectTx{
 		MessageBase: protocol.MessageBase{
 			MessageType: MESSAGE_TYPE_REJECT_TX,
 		},
-		Reason: reason,
+		Reason: cbor.RawMessage(reasonCbor),
 	}
 	return m
 }