Handle case where parent is in previous epoch

multiepoch-getBlock.go

@@ -363,7 +363,9 @@ func (multi *MultiEpoch) handleGetBlock(ctx context.Context, conn *requestContex
 	{
 		// get parent slot
 		parentSlot := uint64(block.Meta.Parent_slot)
-		if parentSlot != 0 {
+		if parentSlot != 0 && CalcEpochForSlot(parentSlot) == epochNumber {
+			// NOTE: if the parent is in the same epoch, we can get it from the same epoch handler as the block;
+			// otherwise, we need to get it from the previous epoch (TODO: implement this)
 			parentBlock, err := epochHandler.GetBlock(WithSubrapghPrefetch(ctx, false), parentSlot)
 			if err != nil {
 				return &jsonrpc2.Error{
@@ -384,6 +386,8 @@ func (multi *MultiEpoch) handleGetBlock(ctx context.Context, conn *requestContex
 				parentEntryHash := solana.HashFromBytes(parentEntryNode.Hash)
 				blockResp.PreviousBlockhash = parentEntryHash.String()
 			}
+		} else {
+			klog.Infof("parent slot is in a different epoch, not implemented yet")
 		}
 	}
 	tim.time("get parent block")