remove hash from Transaction

pkg/serialize/prefix.go

@@ -1,25 +1,20 @@
 package serialize
 
 import (
-	"bytes"
 	"encoding/binary"
 	"fmt"
 )
 
 // addSerializedTypePrefix adds a prefix to the encoded value to indicate the encoding type.
 func addSerializedTypePrefix(encoding encodingType, encodedValue []byte) (SerializedData, error) {
-	result, err := uint16ToBytes(uint16(encoding))
-	if err != nil {
-		return nil, err
-	}
-
-	return append(result, encodedValue...), nil
+	encodingTypeBytes := uint16ToBytes(uint16(encoding))
+	return append(encodingTypeBytes, encodedValue...), nil
 }
 
 // removeSerializedTypePrefix removes the prefix from the encoded value.
 func removeSerializedTypePrefix(data SerializedData) (encodingType, []byte, error) {
-	if len(data) == 0 {
-		return encodingTypeInvalid, nil, fmt.Errorf("cannot deserialize encoded value: data is empty")
+	if len(data) < 3 {
+		return encodingTypeInvalid, nil, fmt.Errorf("cannot deserialize encoded value: data is too short")
 	}
 	typ, err := bytesToUint16(data[:2])
 	if err != nil {
@@ -29,27 +24,17 @@ func removeSerializedTypePrefix(data SerializedData) (encodingType, []byte, erro
 	return encodingType(typ), data[2:], nil
 }
 
-// uint16ToBytes converts a uint16 to a byte slice.
-func uint16ToBytes(n uint16) ([]byte, error) {
-	buf := new(bytes.Buffer)
-	err := binary.Write(buf, binary.BigEndian, n)
-	if err != nil {
-		return nil, err
-	}
-	return buf.Bytes(), nil
+// uint16ToBytes converts a uint16 to a byte slice (big endian).
+func uint16ToBytes(n uint16) []byte {
+	b := make([]byte, 2)
+	binary.BigEndian.PutUint16(b, n)
+	return b
 }
 
 // bytesToUint16 converts a byte slice to a uint16.
 func bytesToUint16(b []byte) (uint16, error) {
-	if len(b) < 2 {
-		return 0, fmt.Errorf("cannot convert bytes to uint16: bytes are too short")
-	}
-
-	buf := bytes.NewReader(b)
-	var n uint16
-	err := binary.Read(buf, binary.BigEndian, &n)
-	if err != nil {
-		return 0, err
+	if len(b) != 2 {
+		return 0, fmt.Errorf("cannot convert bytes to uint16: incorrect length")
 	}
-	return n, nil
+	return binary.BigEndian.Uint16(b), nil
 }

pkg/transactions/transaction.go

@@ -119,24 +119,19 @@ func CreateTransaction(contents Payload, nonce uint64) (*Transaction, error) {
 }
 
 type Transaction struct {
-	// Signature is the signature of the transaction
-	// It can be nil if the transaction is unsigned
+	// Signature is the signature of the transaction.
 	Signature *crypto.Signature
 
-	// Body is the body of the transaction
-	// It gets serialized and signed
+	// Body is the body of the transaction. It gets serialized and signed.
 	Body *TransactionBody
 
 	// Serialization is the serialization performed on `Body`
-	// inorder to generate the message that being signed
+	// in order to generate the message that being signed.
 	Serialization SignedMsgSerializationType
 
 	// Sender is the public key of the sender
 	// NOTE: we could not use crypto.PublicKey, since it's not RLP-serializable
 	Sender []byte
-
-	// hash of the transaction that is signed.  it is kept here as a cache
-	hash []byte
 }
 
 func (t *Transaction) GetSenderPubKey() (crypto.PublicKey, error) {
@@ -189,43 +184,12 @@ func (t *Transaction) Sign(signer crypto.Signer) error {
 	return nil
 }
 
-// GetHash gets the hash for the transaction
-// If a hash has already been generated, it is returned
-func (t *Transaction) GetHash() ([]byte, error) {
-	if t.hash != nil {
-		return t.hash, nil
-	}
-
-	return t.SetHash()
-}
-
-// SetHash re-hashes the transaction and caches the new hash
-func (t *Transaction) SetHash() ([]byte, error) {
-	bts, err := t.Body.MarshalBinary()
-	if err != nil {
-		return nil, err
-	}
-
-	t.hash = crypto.Sha256(bts)
-
-	return t.hash, nil
-}
-
 func (t *Transaction) MarshalBinary() (serialize.SerializedData, error) {
 	return serialize.Encode(t)
 }
 
-// TODO: I am not sure if this will actually work, since it is unserializing into an interface
-// I am quite sure it wont; an alternative is to decode into a struct where public key is bytes, and
-// create the public key from there
 func (t *Transaction) UnmarshalBinary(data serialize.SerializedData) error {
-	res, err := serialize.Decode[Transaction](data)
-	if err != nil {
-		return err
-	}
-
-	*t = *res
-	return nil
+	return serialize.DecodeInto(data, t)
 }
 
 // TransactionBody is the body of a transaction that gets included in the signature

pkg/transactions/transaction_test.go

@@ -8,10 +8,23 @@ import (
 
 	"github.com/kwilteam/kwil-db/pkg/crypto"
 	"github.com/kwilteam/kwil-db/pkg/transactions"
+
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
+// NOTE: this fails because of legacy issues with RLP itself.
+//
+// func Test_TransactionMarshalUnmarshal(t *testing.T) {
+// 	tx := &transactions.Transaction{}
+// 	serialized, err := tx.MarshalBinary()
+// 	require.NoError(t, err)
+
+// 	tx2 := &transactions.Transaction{}
+// 	err = tx2.UnmarshalBinary(serialized)
+// 	require.NoError(t, err)
+// }
+
 // testing serialization of a transaction, since Luke found a bug
 func Test_TransactionMarshal(t *testing.T) {
 	tx := &transactions.Transaction{