Code hygiene: return error instead of bool (#660)

node/grpc/server.go

@@ -2,6 +2,7 @@ package grpc
 
 import (
 	"context"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	"runtime"
@@ -302,10 +303,10 @@ func (s *Server) RetrieveChunks(ctx context.Context, in *pb.RetrieveChunksReques
 		return nil, errors.New("request rate limited")
 	}
 
-	chunks, format, ok := s.node.Store.GetChunks(ctx, batchHeaderHash, int(in.GetBlobIndex()), uint8(in.GetQuorumId()))
-	if !ok {
+	chunks, format, err := s.node.Store.GetChunks(ctx, batchHeaderHash, int(in.GetBlobIndex()), uint8(in.GetQuorumId()))
+	if err != nil {
 		s.node.Metrics.RecordRPCRequest("RetrieveChunks", "failure", time.Since(start))
-		return nil, fmt.Errorf("could not find chunks for batchHeaderHash %v, blob index: %v, quorumID: %v", batchHeaderHash, in.GetBlobIndex(), in.GetQuorumId())
+		return nil, fmt.Errorf("could not find chunks for batchHeaderHash %v, blob index: %v, quorumID: %v", hex.EncodeToString(batchHeaderHash[:]), in.GetBlobIndex(), in.GetQuorumId())
 	}
 	s.node.Metrics.RecordRPCRequest("RetrieveChunks", "success", time.Since(start))
 	return &pb.RetrieveChunksReply{Chunks: chunks, Encoding: format}, nil

node/store.go

@@ -347,26 +347,26 @@ func (s *Store) GetBlobHeader(ctx context.Context, batchHeaderHash [32]byte, blo
 	return data, nil
 }
 
-// GetChunks returns the list of byte arrays stored for given blobKey along with a boolean
-// indicating if the read was unsuccessful or the chunks were serialized correctly
-func (s *Store) GetChunks(ctx context.Context, batchHeaderHash [32]byte, blobIndex int, quorumID core.QuorumID) ([][]byte, node.ChunkEncoding, bool) {
+// GetChunks returns the list of byte arrays stored for given blobKey along with the encoding
+// format of the bytes.
+func (s *Store) GetChunks(ctx context.Context, batchHeaderHash [32]byte, blobIndex int, quorumID core.QuorumID) ([][]byte, node.ChunkEncoding, error) {
 	log := s.logger
 
 	blobKey, err := EncodeBlobKey(batchHeaderHash, blobIndex, quorumID)
 	if err != nil {
-		return nil, node.ChunkEncoding_UNKNOWN, false
+		return nil, node.ChunkEncoding_UNKNOWN, err
 	}
 	data, err := s.db.Get(blobKey)
 	if err != nil {
-		return nil, node.ChunkEncoding_UNKNOWN, false
+		return nil, node.ChunkEncoding_UNKNOWN, err
 	}
 	log.Debug("Retrieved chunk", "blobKey", hexutil.Encode(blobKey), "length", len(data))
 
 	chunks, format, err := DecodeChunks(data)
 	if err != nil {
-		return nil, format, false
+		return nil, format, err
 	}
-	return chunks, format, true
+	return chunks, format, nil
 }
 
 // HasKey returns if a given key has been stored.

node/store_test.go

@@ -331,12 +331,11 @@ func TestStoringBlob(t *testing.T) {
 
 func decodeChunks(t *testing.T, s *node.Store, batchHeaderHash [32]byte, blobIdx int, chunkEncoding pb.ChunkEncoding) []*encoding.Frame {
 	ctx := context.Background()
-	chunks, format, ok := s.GetChunks(ctx, batchHeaderHash, blobIdx, 0)
-	assert.True(t, ok)
+	chunks, format, err := s.GetChunks(ctx, batchHeaderHash, blobIdx, 0)
+	assert.Nil(t, err)
 	assert.Equal(t, 1, len(chunks))
 	assert.Equal(t, chunkEncoding, format)
 	var f *encoding.Frame
-	var err error
 	switch chunkEncoding {
 	case pb.ChunkEncoding_GOB:
 		f, err = new(encoding.Frame).Deserialize(chunks[0])