fix: utilize 'msg' parameter in handleRequestNext and pass it to callback

Signed-off-by: Ales Verbic <[email protected]>

Author: verbotenj

protocol/chainsync/chainsync.go

@@ -219,7 +219,7 @@ type RollBackwardFunc func(CallbackContext, common.Point, Tip) error
 type RollForwardFunc func(CallbackContext, uint, interface{}, Tip) error
 
 type FindIntersectFunc func(CallbackContext, []common.Point) (common.Point, Tip, error)
-type RequestNextFunc func(CallbackContext) error
+type RequestNextFunc func(CallbackContext, *MsgRequestNext) error
 
 // New returns a new ChainSync object
 func New(protoOptions protocol.ProtocolOptions, cfg *Config) *ChainSync {

protocol/chainsync/messages_test.go

@@ -17,14 +17,15 @@ package chainsync
 import (
 	"encoding/hex"
 	"fmt"
-	"github.com/blinklabs-io/gouroboros/cbor"
-	"github.com/blinklabs-io/gouroboros/ledger"
-	"github.com/blinklabs-io/gouroboros/protocol"
-	"github.com/blinklabs-io/gouroboros/protocol/common"
 	"os"
 	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/blinklabs-io/gouroboros/cbor"
+	"github.com/blinklabs-io/gouroboros/ledger"
+	"github.com/blinklabs-io/gouroboros/protocol"
+	"github.com/blinklabs-io/gouroboros/protocol/common"
 )
 
 type testDefinition struct {

protocol/chainsync/server.go

@@ -131,7 +131,12 @@ func (s *Server) handleRequestNext(msg protocol.Message) error {
 			"received chain-sync RequestNext message but no callback function is defined",
 		)
 	}
-	return s.config.RequestNextFunc(s.callbackContext)
+	msgRequestNext, ok := msg.(*MsgRequestNext)
+	if !ok {
+		return fmt.Errorf("expected MsgRequestNext, got %T", msg)
+	}
+	// Pass the message to the callback function
+	return s.config.RequestNextFunc(s.callbackContext, msgRequestNext)
 }
 
 func (s *Server) handleFindIntersect(msg protocol.Message) error {

protocol/chainsync/server_test.go

@@ -0,0 +1,88 @@
+// Copyright 2024 Blink Labs Software
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chainsync
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHandleRequestNext_ValidMessage(t *testing.T) {
+	called := false
+	var receivedMsg *MsgRequestNext
+
+	server := &Server{
+		config: &Config{
+			RequestNextFunc: func(ctx CallbackContext, msg *MsgRequestNext) error {
+				called = true
+				receivedMsg = msg
+				// Ensure that the CBOR data is not empty
+				if len(msg.Cbor()) == 0 {
+					return fmt.Errorf("expected non-empty CBOR data")
+				}
+				return nil
+			},
+		},
+		callbackContext: CallbackContext{},
+	}
+
+	msg := &MsgRequestNext{}
+	// Fake CBOR data
+	rawCborData := []byte{0x01, 0x02, 0x03}
+	msg.SetCbor(rawCborData)
+
+	err := server.handleRequestNext(msg)
+
+	assert.NoError(t, err, "expected no error")
+	assert.True(t, called, "expected RequestNextFunc to be called")
+	assert.Equal(t, msg, receivedMsg, "expected received message to be the same as sent message")
+	assert.Equal(t, rawCborData, receivedMsg.Cbor(), "expected raw CBOR data to be passed correctly")
+}
+
+func TestHandleRequestNext_InvalidMessageType(t *testing.T) {
+	server := &Server{
+		config: &Config{
+			RequestNextFunc: func(ctx CallbackContext, msg *MsgRequestNext) error {
+				return nil
+			},
+		},
+		callbackContext: CallbackContext{},
+	}
+
+	msg := &MsgFindIntersect{}
+	err := server.handleRequestNext(msg)
+	expectedError := fmt.Sprintf("expected MsgRequestNext, got %T", msg)
+
+	assert.Error(t, err, "expected an error due to invalid message type")
+	assert.EqualError(t, err, expectedError)
+}
+
+func TestHandleRequestNext_NilCallback(t *testing.T) {
+	server := &Server{
+		config: &Config{
+			RequestNextFunc: nil,
+		},
+		callbackContext: CallbackContext{},
+	}
+
+	msg := &MsgRequestNext{}
+	err := server.handleRequestNext(msg)
+	expectedError := "received chain-sync RequestNext message but no callback function is defined"
+
+	assert.Error(t, err, "expected an error due to nil callback")
+	assert.EqualError(t, err, expectedError)
+}