feat: introduce safe and finalized as block number filters (#412)

* feat: introduce safe and finalized as block number filtes

* address comment

e2e-polybft/e2e/jsonrpc_test.go

@@ -95,6 +95,18 @@ func TestE2E_JsonRPC(t *testing.T) {
 		// since we asked for the full block, and epoch ending block has a transaction
 		require.Equal(t, 1, len(blockByHash.Transactions))
 
+		// get safe block (act as the latest, because of the instant finality)
+		safeBlock, err := ethClient.GetBlockByNumber(jsonrpc.SafeBlockNumber, false)
+		require.NoError(t, err)
+		require.NotNil(t, safeBlock)
+		require.GreaterOrEqual(t, safeBlock.Number(), epochSize)
+
+		// get finalized block (act as the latest, because of the instant finality)
+		finalizedBlock, err := ethClient.GetBlockByNumber(jsonrpc.FinalizedBlockNumber, false)
+		require.NoError(t, err)
+		require.NotNil(t, finalizedBlock)
+		require.GreaterOrEqual(t, finalizedBlock.Number(), epochSize)
+
 		// get latest block
 		latestBlock, err := ethClient.GetBlockByNumber(jsonrpc.LatestBlockNumber, false)
 		require.NoError(t, err)

jsonrpc/codec.go

@@ -10,12 +10,18 @@ import (
 )
 
 func init() {
-	pendingBN := PendingBlockNumber
-	PendingBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &pendingBN}
+	safeBN := SafeBlockNumber
+	SafeBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &safeBN}
+
+	finalizedBN := FinalizedBlockNumber
+	FinalizedBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &finalizedBN}
 
 	latestBN := LatestBlockNumber
 	LatestBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &latestBN}
 
+	pendingBN := PendingBlockNumber
+	PendingBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &pendingBN}
+
 	earliestBN := EarliestBlockNumber
 	EarliestBlockNumberOrHash = BlockNumberOrHash{BlockNumber: &earliestBN}
 }
@@ -127,32 +133,42 @@ func (e *ObjectError) MarshalJSON() ([]byte, error) {
 }
 
 const (
-	pending  = "pending"
-	latest   = "latest"
-	earliest = "earliest"
+	safe      = "safe"
+	finalized = "finalized"
+	latest    = "latest"
+	pending   = "pending"
+	earliest  = "earliest"
 )
 
 const (
-	PendingBlockNumber  = BlockNumber(-3)
-	LatestBlockNumber   = BlockNumber(-2)
-	EarliestBlockNumber = BlockNumber(-1)
+	SafeBlockNumber      = BlockNumber(-4)
+	FinalizedBlockNumber = BlockNumber(-3)
+	LatestBlockNumber    = BlockNumber(-2)
+	PendingBlockNumber   = BlockNumber(-1)
+	EarliestBlockNumber  = BlockNumber(0)
 )
 
 var (
-	PendingBlockNumberOrHash  BlockNumberOrHash
-	LatestBlockNumberOrHash   BlockNumberOrHash
-	EarliestBlockNumberOrHash BlockNumberOrHash
+	SafeBlockNumberOrHash      BlockNumberOrHash
+	FinalizedBlockNumberOrHash BlockNumberOrHash
+	LatestBlockNumberOrHash    BlockNumberOrHash
+	PendingBlockNumberOrHash   BlockNumberOrHash
+	EarliestBlockNumberOrHash  BlockNumberOrHash
 )
 
 type BlockNumber int64
 
 // String returns the string representation of the block number
 func (b BlockNumber) String() string {
 	switch b {
-	case PendingBlockNumber:
-		return pending
+	case SafeBlockNumber:
+		return safe
+	case FinalizedBlockNumber:
+		return finalized
 	case LatestBlockNumber:
 		return latest
+	case PendingBlockNumber:
+		return pending
 	case EarliestBlockNumber:
 		return earliest
 	}
@@ -231,10 +247,14 @@ func stringToBlockNumber(str string) (BlockNumber, error) {
 
 	str = strings.Trim(str, "\"")
 	switch str {
-	case pending:
-		return PendingBlockNumber, nil
+	case safe:
+		return SafeBlockNumber, nil
+	case finalized:
+		return FinalizedBlockNumber, nil
 	case latest:
 		return LatestBlockNumber, nil
+	case pending:
+		return PendingBlockNumber, nil
 	case earliest:
 		return EarliestBlockNumber, nil
 	}
@@ -269,11 +289,11 @@ func (b *BlockNumber) UnmarshalJSON(buffer []byte) error {
 }
 
 // NewRPCErrorResponse is used to create a custom error response
-func NewRPCErrorResponse(id interface{}, errCode int, err string, data []byte, jsonrpcver string) Response {
-	errObject := &ObjectError{errCode, err, data}
+func NewRPCErrorResponse(id interface{}, errCode int, err string, data []byte, jsonRPCVersion string) Response {
+	errObject := &ObjectError{Code: errCode, Message: err, Data: data}
 
 	response := &ErrorResponse{
-		JSONRPC: jsonrpcver,
+		JSONRPC: jsonRPCVersion,
 		ID:      id,
 		Error:   errObject,
 	}
@@ -282,13 +302,13 @@ func NewRPCErrorResponse(id interface{}, errCode int, err string, data []byte, j
 }
 
 // NewRPCResponse returns Success/Error response object
-func NewRPCResponse(id interface{}, jsonrpcver string, reply []byte, err Error) Response {
+func NewRPCResponse(id interface{}, jsonRPCVersion string, reply []byte, err Error) Response {
 	var response Response
 	switch err.(type) {
 	case nil:
-		response = &SuccessResponse{JSONRPC: jsonrpcver, ID: id, Result: reply}
+		response = &SuccessResponse{JSONRPC: jsonRPCVersion, ID: id, Result: reply}
 	default:
-		response = NewRPCErrorResponse(id, err.ErrorCode(), err.Error(), reply, jsonrpcver)
+		response = NewRPCErrorResponse(id, err.ErrorCode(), err.Error(), reply, jsonRPCVersion)
 	}
 
 	return response

jsonrpc/codec_test.go

@@ -15,6 +15,8 @@ func TestBlockNumberOrHash_UnmarshalJSON(t *testing.T) {
 	assert.NoError(t, err)
 
 	blockNumberZero := BlockNumber(0x0)
+	blockNumberSafe := SafeBlockNumber
+	blockNumberFinalized := FinalizedBlockNumber
 	blockNumberLatest := LatestBlockNumber
 	blockNumberPending := PendingBlockNumber
 
@@ -51,6 +53,22 @@ func TestBlockNumberOrHash_UnmarshalJSON(t *testing.T) {
 			true,
 			BlockNumberOrHash{},
 		},
+		{
+			"should unmarshal safe block number properly",
+			`"safe"`,
+			false,
+			BlockNumberOrHash{
+				BlockNumber: &blockNumberSafe,
+			},
+		},
+		{
+			"should unmarshal finalized block number properly",
+			`"finalized"`,
+			false,
+			BlockNumberOrHash{
+				BlockNumber: &blockNumberFinalized,
+			},
+		},
 		{
 			"should unmarshal latest block number properly",
 			`"latest"`,

jsonrpc/helper.go

@@ -30,7 +30,13 @@ type latestHeaderGetter interface {
 // GetNumericBlockNumber returns block number based on current state or specified number
 func GetNumericBlockNumber(number BlockNumber, store latestHeaderGetter) (uint64, error) {
 	switch number {
-	case LatestBlockNumber, PendingBlockNumber:
+	case SafeBlockNumber:
+		fallthrough
+	case FinalizedBlockNumber:
+		fallthrough
+	case LatestBlockNumber:
+		fallthrough
+	case PendingBlockNumber:
 		latest := store.Header()
 		if latest == nil {
 			return 0, ErrLatestNotFound
@@ -74,7 +80,13 @@ type headerGetter interface {
 // GetBlockHeader returns a header using the provided number
 func GetBlockHeader(number BlockNumber, store headerGetter) (*types.Header, error) {
 	switch number {
-	case PendingBlockNumber, LatestBlockNumber:
+	case SafeBlockNumber:
+		fallthrough
+	case FinalizedBlockNumber:
+		fallthrough
+	case LatestBlockNumber:
+		fallthrough
+	case PendingBlockNumber:
 		return store.Header(), nil
 
 	case EarliestBlockNumber:

jsonrpc/helper_test.go

@@ -127,6 +127,32 @@ func TestGetNumericBlockNumber(t *testing.T) {
 			expected: 10,
 			err:      nil,
 		},
+		{
+			name: "should return the latest block's number for finalized block",
+			num:  FinalizedBlockNumber,
+			store: &debugEndpointMockStore{
+				headerFn: func() *types.Header {
+					return &types.Header{
+						Number: 10,
+					}
+				},
+			},
+			expected: 10,
+			err:      nil,
+		},
+		{
+			name: "should return the latest block's number for safe block",
+			num:  SafeBlockNumber,
+			store: &debugEndpointMockStore{
+				headerFn: func() *types.Header {
+					return &types.Header{
+						Number: 20,
+					}
+				},
+			},
+			expected: 20,
+			err:      nil,
+		},
 		{
 			name: "should return error if the latest block's number is not found",
 			num:  LatestBlockNumber,