func addLink(ctx context.Context, ds dag.DAGService, root *dag.Node, childname string, childnd *dag.Node) (*dag.Node, 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 ImportTar(r io.Reader, ds dag.DAGService) (*dag.Node, error) {
rall, err := ioutil.ReadAll(r)
if err != nil {
return nil, err
}
r = bytes.NewReader(rall)
tr := tar.NewReader(r)
root := new(dag.Node)
root.Data = []byte("ipfs/tar")
e := dagutil.NewDagEditor(root, ds)
for {
h, err := tr.Next()
if err != nil {
if err == io.EOF {
break
}
return nil, err
}
header := new(dag.Node)
headerBytes, err := marshalHeader(h)
if err != nil {
return nil, err
}
header.Data = headerBytes
if h.Size > 0 {
spl := chunk.NewRabin(tr, uint64(chunk.DefaultBlockSize))
nd, err := importer.BuildDagFromReader(ds, spl)
if err != nil {
return nil, err
}
err = header.AddNodeLinkClean("data", nd)
if err != nil {
return nil, err
}
}
_, err = ds.Add(header)
if err != nil {
return nil, err
}
path := escapePath(h.Name)
err = e.InsertNodeAtPath(context.Background(), path, header, func() *dag.Node { return new(dag.Node) })
if err != nil {
return nil, err
}
}
return e.Finalize(ds)
}
func AddMetadataTo(n *core.IpfsNode, skey string, m *ft.Metadata) (string, error) {
ukey := key.B58KeyDecode(skey)
nd, err := n.DAG.Get(n.Context(), ukey)
if err != nil {
return "", err
}
mdnode := new(dag.Node)
mdata, err := ft.BytesForMetadata(m)
if err != nil {
return "", err
}
mdnode.Data = mdata
if err := mdnode.AddNodeLinkClean("file", nd); err != nil {
return "", err
}
nk, err := n.DAG.Add(mdnode)
if err != nil {
return "", err
}
return nk.B58String(), nil
}
func insertNodeAtPath(ctx context.Context, ds dag.DAGService, root *dag.Node, path []string, toinsert key.Key, create func() *dag.Node) (*dag.Node, error) {
if len(path) == 1 {
return addLink(ctx, ds, root, path[0], toinsert)
}
nd, err := root.GetLinkedNode(ctx, ds, path[0])
if err != nil {
// if 'create' is true, we create directories on the way down as needed
if err == dag.ErrNotFound && create != nil {
nd = create()
} else {
return nil, err
}
}
ndprime, err := insertNodeAtPath(ctx, ds, nd, path[1:], toinsert, create)
if err != nil {
return nil, err
}
_ = root.RemoveNodeLink(path[0])
err = root.AddNodeLinkClean(path[0], ndprime)
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
func (e *Editor) rmLink(ctx context.Context, root *dag.Node, path []string) (*dag.Node, 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.GetLinkedNode(ctx, e.tmp, path[0])
if err == dag.ErrNotFound {
nd, err = root.GetLinkedNode(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.Node, path []string, toinsert *dag.Node, create func() *dag.Node) (*dag.Node, error) {
if len(path) == 1 {
return addLink(ctx, e.tmp, root, path[0], toinsert)
}
nd, err := root.GetLinkedNode(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.GetLinkedNode(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
}
func addLink(ctx context.Context, ds dag.DAGService, root *dag.Node, childname string, childk key.Key) (*dag.Node, error) {
ctx, cancel := context.WithTimeout(ctx, time.Second*30)
childnd, err := ds.Get(ctx, childk)
if err != nil {
cancel()
return nil, err
}
cancel()
err = root.AddNodeLinkClean(childname, childnd)
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
func rmLink(ctx context.Context, ds dag.DAGService, root *dag.Node, path []string) (*dag.Node, error) {
if len(path) == 1 {
// base case, remove node in question
err := root.RemoveNodeLink(path[0])
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
nd, err := root.GetLinkedNode(ctx, ds, path[0])
if err != nil {
return nil, err
}
nnode, err := rmLink(ctx, ds, nd, path[1:])
if err != nil {
return nil, err
}
_ = root.RemoveNodeLink(path[0])
err = root.AddNodeLinkClean(path[0], nnode)
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
func insertNodeAtPath(ctx context.Context, ds dag.DAGService, root *dag.Node, path []string, toinsert key.Key) (*dag.Node, error) {
if len(path) == 1 {
return addLink(ctx, ds, root, path[0], toinsert)
}
child, err := root.GetNodeLink(path[0])
if err != nil {
return nil, err
}
nd, err := child.GetNode(ctx, ds)
if err != nil {
return nil, err
}
ndprime, err := insertNodeAtPath(ctx, ds, nd, path[1:], toinsert)
if err != nil {
return nil, err
}
err = root.RemoveNodeLink(path[0])
if err != nil {
return nil, err
}
err = root.AddNodeLinkClean(path[0], ndprime)
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
func addLink(ctx context.Context, ds dag.DAGService, root *dag.Node, childname string, childk key.Key) (*dag.Node, error) {
if childname == "" {
return nil, errors.New("cannot create link with no name!")
}
childnd, err := ds.Get(ctx, childk)
if err != nil {
return nil, err
}
// ensure no link with that name already exists
_ = root.RemoveNodeLink(childname) // ignore error, only option is ErrNotFound
err = root.AddNodeLinkClean(childname, childnd)
if err != nil {
return nil, err
}
_, err = ds.Add(root)
if err != nil {
return nil, err
}
return root, nil
}
// dagTruncate truncates the given node to 'size' and returns the modified Node
func dagTruncate(ctx context.Context, nd *mdag.Node, size uint64, ds mdag.DAGService) (*mdag.Node, error) {
if len(nd.Links) == 0 {
// TODO: this can likely be done without marshaling and remarshaling
pbn, err := ft.FromBytes(nd.Data)
if err != nil {
return nil, err
}
nd.Data = ft.WrapData(pbn.Data[:size])
return nd, nil
}
var cur uint64
end := 0
var modified *mdag.Node
ndata := new(ft.FSNode)
for i, lnk := range nd.Links {
child, err := lnk.GetNode(ctx, ds)
if err != nil {
return nil, err
}
childsize, err := ft.DataSize(child.Data)
if err != nil {
return nil, err
}
// found the child we want to cut
if size < cur+childsize {
nchild, err := dagTruncate(ctx, child, size-cur, ds)
if err != nil {
return nil, err
}
ndata.AddBlockSize(size - cur)
modified = nchild
end = i
break
}
cur += childsize
ndata.AddBlockSize(childsize)
}
_, err := ds.Add(modified)
if err != nil {
return nil, err
}
nd.Links = nd.Links[:end]
err = nd.AddNodeLinkClean("", modified)
if err != nil {
return nil, err
}
d, err := ndata.GetBytes()
if err != nil {
return nil, err
}
nd.Data = d
// invalidate cache and recompute serialized data
_, err = nd.Encoded(true)
if err != nil {
return nil, err
}
return nd, nil
}