Merge pull request #2384 from ipfs/feat/dag-refactor

refactor merkledag fetching methods

archive/tar/writer.go

@@ -39,7 +39,7 @@ func (w *Writer) writeDir(nd *mdag.Node, fpath string) error {
 		return err
 	}
 
-	for i, ng := range w.Dag.GetDAG(w.ctx, nd) {
+	for i, ng := range mdag.GetDAG(w.ctx, w.Dag, nd) {
 		child, err := ng.Get(w.ctx)
 		if err != nil {
 			return err

io/dagreader.go

@@ -90,7 +90,7 @@ func NewDagReader(ctx context.Context, n *mdag.Node, serv mdag.DAGService) (*Dag
 
 func NewDataFileReader(ctx context.Context, n *mdag.Node, pb *ftpb.Data, serv mdag.DAGService) *DagReader {
 	fctx, cancel := context.WithCancel(ctx)
-	promises := serv.GetDAG(fctx, n)
+	promises := mdag.GetDAG(fctx, serv, n)
 	return &DagReader{
 		node:     n,
 		serv:     serv,