Merge pull request #55 from ipfs/feat/error-on-failed-preload

Fail to construct preload hamt shards when traversal fails

hamt/shardeddir.go

@@ -65,10 +65,13 @@ func NewUnixFSHAMTShardWithPreload(ctx context.Context, substrate dagpb.PBNode,
  return n, err
  }
 
- traverse := n.Length()
+ traverse, err := n.(*_UnixFSHAMTShard).length()
  if traverse == -1 {
  return n, fmt.Errorf("could not fully explore hamt during preload")
  }
+ if err != nil {
+ return n, err
+ }
 
  return n, nil
 }
@@ -261,9 +264,9 @@ func (n UnixFSHAMTShard) ListIterator() ipld.ListIterator {
 
 // Length returns the length of a list, or the number of entries in a map,
 // or -1 if the node is not of list nor map kind.
-func (n UnixFSHAMTShard) Length() int64 {
+func (n UnixFSHAMTShard) length() (int64, error) {
  if n.cachedLength != -1 {
- return n.cachedLength
+ return n.cachedLength, nil
  }
  maxPadLen := maxPadLength(n.data)
  total := int64(0)
@@ -272,20 +275,34 @@ func (n UnixFSHAMTShard) Length() int64 {
  _, pbLink := itr.Next()
  isValue, err := isValueLink(pbLink, maxPadLen)
  if err != nil {
- continue
+ return 0, err
  }
  if isValue {
  total++
  } else {
  child, err := n.loadChild(pbLink)
  if err != nil {
- continue
+ return 0, err
  }
- total += child.Length()
+ cl, err := child.length()
+ if err != nil {
+ return 0, err
+ }
+ total += cl
  }
  }
  n.cachedLength = total
- return total
+ return total, nil
+}
+
+// Length returns the length of a list, or the number of entries in a map,
+// or -1 if the node is not of list nor map kind.
+func (n UnixFSHAMTShard) Length() int64 {
+ len, err := n.length()
+ if err != nil {
+ return 0
+ }
+ return len
 }
 
 func (n UnixFSHAMTShard) IsAbsent() bool {