func addLink(ctx context.Context, ds dag.DAGService, root *dag.ProtoNode, childname string, childnd node.Node) (*dag.ProtoNode, error) {
if childname == "" {
return nil, errors.New("cannot create link with no name!")
}
// ensure that the node we are adding is in the dagservice
_, err := ds.Add(childnd)
if err != nil {
return nil, err
}
_ = ds.Remove(root)
// ensure no link with that name already exists
_ = root.RemoveNodeLink(childname) // ignore error, only option is ErrNotFound
if err := root.AddNodeLinkClean(childname, childnd); err != nil {
return nil, err
}
if _, err := ds.Add(root); err != nil {
return nil, err
}
return root, nil
}
func (e *Editor) rmLink(ctx context.Context, root *dag.ProtoNode, path []string) (*dag.ProtoNode, error) {
if len(path) == 1 {
// base case, remove node in question
err := root.RemoveNodeLink(path[0])
if err != nil {
return nil, err
}
_, err = e.tmp.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
// search for node in both tmp dagstore and source dagstore
nd, err := root.GetLinkedProtoNode(ctx, e.tmp, path[0])
if err == dag.ErrNotFound {
nd, err = root.GetLinkedProtoNode(ctx, e.src, path[0])
}
if err != nil {
return nil, err
}
nnode, err := e.rmLink(ctx, nd, path[1:])
if err != nil {
return nil, err
}
_ = e.tmp.Remove(root)
_ = root.RemoveNodeLink(path[0])
err = root.AddNodeLinkClean(path[0], nnode)
if err != nil {
return nil, err
}
_, err = e.tmp.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
func (e *Editor) insertNodeAtPath(ctx context.Context, root *dag.ProtoNode, path []string, toinsert node.Node, create func() *dag.ProtoNode) (*dag.ProtoNode, error) {
if len(path) == 1 {
return addLink(ctx, e.tmp, root, path[0], toinsert)
}
nd, err := root.GetLinkedProtoNode(ctx, e.tmp, path[0])
if err != nil {
// if 'create' is true, we create directories on the way down as needed
if err == dag.ErrLinkNotFound && create != nil {
nd = create()
err = nil // no longer an error case
} else if err == dag.ErrNotFound {
// try finding it in our source dagstore
nd, err = root.GetLinkedProtoNode(ctx, e.src, path[0])
}
// if we receive an ErrNotFound, then our second 'GetLinkedNode' call
// also fails, we want to error out
if err != nil {
return nil, err
}
}
ndprime, err := e.insertNodeAtPath(ctx, nd, path[1:], toinsert, create)
if err != nil {
return nil, err
}
_ = e.tmp.Remove(root)
_ = root.RemoveNodeLink(path[0])
err = root.AddNodeLinkClean(path[0], ndprime)
if err != nil {
return nil, err
}
_, err = e.tmp.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
