Merge pull request #794 from jbenet/feat/refs-faster

teach ipfs refs -r how to use GetBlocks

core/commands/refs.go

@@ -227,6 +227,14 @@ type RefWriter struct {
 
 // WriteRefs writes refs of the given object to the underlying writer.
 func (rw *RefWriter) WriteRefs(n *dag.Node) (int, error) {
+	if rw.Recursive {
+		return rw.writeRefsRecursive(n)
+	} else {
+		return rw.writeRefsSingle(n)
+	}
+}
+
+func (rw *RefWriter) writeRefsRecursive(n *dag.Node) (int, error) {
 	nkey, err := n.Key()
 	if err != nil {
 		return 0, err
@@ -236,29 +244,23 @@ func (rw *RefWriter) WriteRefs(n *dag.Node) (int, error) {
 		return 0, nil
 	}
 
-	count := 0
-	for _, l := range n.Links {
-		lk := u.Key(l.Hash)
-
+	var count int
+	for i, ng := range rw.DAG.GetDAG(rw.Ctx, n) {
+		lk := u.Key(n.Links[i].Hash)
 		if rw.skip(lk) {
 			continue
 		}
 
-		if err := rw.WriteEdge(nkey, lk, l.Name); err != nil {
+		if err := rw.WriteEdge(nkey, lk, n.Links[i].Name); err != nil {
 			return count, err
 		}
-		count++
 
-		if !rw.Recursive {
-			continue
-		}
-
-		child, err := l.GetNode(rw.DAG)
+		nd, err := ng.Get()
 		if err != nil {
 			return count, err
 		}
 
-		c, err := rw.WriteRefs(child)
+		c, err := rw.writeRefsRecursive(nd)
 		count += c
 		if err != nil {
 			return count, err
@@ -267,6 +269,32 @@ func (rw *RefWriter) WriteRefs(n *dag.Node) (int, error) {
 	return count, nil
 }
 
+func (rw *RefWriter) writeRefsSingle(n *dag.Node) (int, error) {
+	nkey, err := n.Key()
+	if err != nil {
+		return 0, err
+	}
+
+	if rw.skip(nkey) {
+		return 0, nil
+	}
+
+	count := 0
+	for _, l := range n.Links {
+		lk := u.Key(l.Hash)
+
+		if rw.skip(lk) {
+			continue
+		}
+
+		if err := rw.WriteEdge(nkey, lk, l.Name); err != nil {
+			return count, err
+		}
+		count++
+	}
+	return count, nil
+}
+
 // skip returns whether to skip a key
 func (rw *RefWriter) skip(k u.Key) bool {
 	if !rw.Unique {