Tested signature middleware with standard tx wrappers

txs/base.go

@@ -9,7 +9,8 @@ import (
 
 const (
 	// for utils...
-	ByteRaw   = 0x1
+	ByteRaw = 0x1
+	// TODO: move fees into a module, multiplexer is standard
 	ByteFees  = 0x2
 	ByteMulti = 0x3
 	ByteChain = 0x4

txs/sigs.go

@@ -49,6 +49,7 @@ type OneSig struct {
 }
 
 var _ keys.Signable = &OneSig{}
+var _ basecoin.TxLayer = &OneSig{}
 
 func NewSig(tx basecoin.Tx) *OneSig {
 	return &OneSig{Tx: tx}
@@ -58,6 +59,10 @@ func (s *OneSig) Wrap() basecoin.Tx {
 	return basecoin.Tx{s}
 }
 
+func (s *OneSig) Next() basecoin.Tx {
+	return s.Tx
+}
+
 func (s *OneSig) ValidateBasic() error {
 	// TODO: VerifyBytes here, we do it in Signers?
 	if s.Empty() || !s.Pubkey.VerifyBytes(s.SignBytes(), s.Sig) {
@@ -119,6 +124,7 @@ type MultiSig struct {
 }
 
 var _ keys.Signable = &MultiSig{}
+var _ basecoin.TxLayer = &MultiSig{}
 
 func NewMulti(tx basecoin.Tx) *MultiSig {
 	return &MultiSig{Tx: tx}
@@ -128,6 +134,10 @@ func (s *MultiSig) Wrap() basecoin.Tx {
 	return basecoin.Tx{s}
 }
 
+func (s *MultiSig) Next() basecoin.Tx {
+	return s.Tx
+}
+
 func (s *MultiSig) ValidateBasic() error {
 	// TODO: more efficient
 	_, err := s.Signers()
@@ -185,3 +195,10 @@ func (s *MultiSig) Signers() ([]crypto.PubKey, error) {
 
 	return keys, nil
 }
+
+func Sign(tx keys.Signable, key crypto.PrivKey) error {
+	msg := tx.SignBytes()
+	pubkey := key.PubKey()
+	sig := key.Sign(msg)
+	return tx.Sign(pubkey, sig)
+}