Golint: unixfs/io

License: MIT
Signed-off-by: Hector Sanjuan <hector@protocol.ai>

unixfs/io/bufdagreader.go

@@ -10,7 +10,9 @@ type bufDagReader struct {
 	*bytes.Reader
 }
 
-func NewBufDagReader(b []byte) *bufDagReader {
+// newBufDagReader returns a DAG reader for the given byte slice.
+// BufDagReader is used to read RawNodes.
+func newBufDagReader(b []byte) *bufDagReader {
 	return &bufDagReader{bytes.NewReader(b)}
 }
 

unixfs/io/dagreader.go

@@ -14,10 +14,15 @@ import (
 	ipld "gx/ipfs/Qme5bWv7wtjUNGsK2BNGVUFPKiuxWrsqrtvYwCLRw8YFES/go-ipld-format"
 )
 
-var ErrIsDir = errors.New("this dag node is a directory")
-
-var ErrCantReadSymlinks = errors.New("cannot currently read symlinks")
+// Common errors
+var (
+	ErrIsDir            = errors.New("this dag node is a directory")
+	ErrCantReadSymlinks = errors.New("cannot currently read symlinks")
+)
 
+// A DagReader represents a ReadSeekCloser which offers additional methods
+// like Size. Different implementations of readers are used for the different
+// types of unixfs/protobuf-encoded nodes.
 type DagReader interface {
 	ReadSeekCloser
 	Size() uint64
@@ -25,6 +30,7 @@ type DagReader interface {
 	Offset() int64
 }
 
+// A ReadSeekCloser implements interfaces to read, write, seek and close.
 type ReadSeekCloser interface {
 	io.Reader
 	io.Seeker
@@ -37,7 +43,7 @@ type ReadSeekCloser interface {
 func NewDagReader(ctx context.Context, n ipld.Node, serv ipld.NodeGetter) (DagReader, error) {
 	switch n := n.(type) {
 	case *mdag.RawNode:
-		return NewBufDagReader(n.RawData()), nil
+		return newBufDagReader(n.RawData()), nil
 	case *mdag.ProtoNode:
 		pb := new(ftpb.Data)
 		if err := proto.Unmarshal(n.Data(), pb); err != nil {

unixfs/io/dagreader_test.go

@@ -102,7 +102,7 @@ func TestSeekAndReadLarge(t *testing.T) {
 		t.Fatal("seeked read failed")
 	}
 
-	pbdr := reader.(*pbDagReader)
+	pbdr := reader.(*PBDagReader)
 	var count int
 	for i, p := range pbdr.promises {
 		if i > 20 && i < 30 {

unixfs/io/dirbuilder.go

@@ -8,8 +8,8 @@ import (
 	mdag "github.com/ipfs/go-ipfs/merkledag"
 	format "github.com/ipfs/go-ipfs/unixfs"
 	hamt "github.com/ipfs/go-ipfs/unixfs/hamt"
-	cid "gx/ipfs/QmcZfnkapfECQGcLZaf9B79NRg7cRa9EnZh4LSbkCzwNvY/go-cid"
 
+	cid "gx/ipfs/QmcZfnkapfECQGcLZaf9B79NRg7cRa9EnZh4LSbkCzwNvY/go-cid"
 	ipld "gx/ipfs/Qme5bWv7wtjUNGsK2BNGVUFPKiuxWrsqrtvYwCLRw8YFES/go-ipld-format"
 )
 
@@ -25,11 +25,14 @@ var UseHAMTSharding = false
 // DefaultShardWidth is the default value used for hamt sharding width.
 var DefaultShardWidth = 256
 
+// Directory allows to work with UnixFS directory nodes, adding and removing
+// children. It allows to work with different directory schemes,
+// like the classic or the HAMT one.
 type Directory struct {
 	dserv   ipld.DAGService
 	dirnode *mdag.ProtoNode
 
-	shard *hamt.HamtShard
+	shard *hamt.Shard
 }
 
 // NewDirectory returns a Directory. It needs a DAGService to add the Children
@@ -37,7 +40,7 @@ func NewDirectory(dserv ipld.DAGService) *Directory {
 	db := new(Directory)
 	db.dserv = dserv
 	if UseHAMTSharding {
-		s, err := hamt.NewHamtShard(dserv, DefaultShardWidth)
+		s, err := hamt.NewShard(dserv, DefaultShardWidth)
 		if err != nil {
 			panic(err) // will only panic if DefaultShardWidth is a bad value
 		}
@@ -113,7 +116,7 @@ func (d *Directory) AddChild(ctx context.Context, name string, nd ipld.Node) err
 }
 
 func (d *Directory) switchToSharding(ctx context.Context) error {
-	s, err := hamt.NewHamtShard(d.dserv, DefaultShardWidth)
+	s, err := hamt.NewShard(d.dserv, DefaultShardWidth)
 	if err != nil {
 		return err
 	}
@@ -136,6 +139,7 @@ func (d *Directory) switchToSharding(ctx context.Context) error {
 	return nil
 }
 
+// ForEachLink applies the given function to Links in the directory.
 func (d *Directory) ForEachLink(ctx context.Context, f func(*ipld.Link) error) error {
 	if d.shard == nil {
 		for _, l := range d.dirnode.Links() {
@@ -149,6 +153,7 @@ func (d *Directory) ForEachLink(ctx context.Context, f func(*ipld.Link) error) e
 	return d.shard.ForEachLink(ctx, f)
 }
 
+// Links returns the all the links in the directory node.
 func (d *Directory) Links(ctx context.Context) ([]*ipld.Link, error) {
 	if d.shard == nil {
 		return d.dirnode.Links(), nil
@@ -157,6 +162,9 @@ func (d *Directory) Links(ctx context.Context) ([]*ipld.Link, error) {
 	return d.shard.EnumLinks(ctx)
 }
 
+// Find returns the ipld.Node with the given name, if it is contained in this
+// directory. Find only searches in the most inmediate links, and not
+// recursively in the tree.
 func (d *Directory) Find(ctx context.Context, name string) (ipld.Node, error) {
 	if d.shard == nil {
 		lnk, err := d.dirnode.GetNodeLink(name)
@@ -179,6 +187,7 @@ func (d *Directory) Find(ctx context.Context, name string) (ipld.Node, error) {
 	return lnk.GetNode(ctx, d.dserv)
 }
 
+// RemoveChild removes the child with the given name.
 func (d *Directory) RemoveChild(ctx context.Context, name string) error {
 	if d.shard == nil {
 		return d.dirnode.RemoveNodeLink(name)

unixfs/io/doc.go

-// package unixfs/io implements convenience objects for working with the ipfs
+// Package io implements convenience objects for working with the ipfs
 // unixfs data format.
 package io

unixfs/io/pbdagreader.go

@@ -15,8 +15,8 @@ import (
 	ipld "gx/ipfs/Qme5bWv7wtjUNGsK2BNGVUFPKiuxWrsqrtvYwCLRw8YFES/go-ipld-format"
 )
 
-// DagReader provides a way to easily read the data contained in a dag.
-type pbDagReader struct {
+// PBDagReader provides a way to easily read the data contained in a dag.
+type PBDagReader struct {
 	serv ipld.NodeGetter
 
 	// the node being read
@@ -48,16 +48,16 @@ type pbDagReader struct {
 	cancel func()
 }
 
-var _ DagReader = (*pbDagReader)(nil)
+var _ DagReader = (*PBDagReader)(nil)
 
 // NewPBFileReader constructs a new PBFileReader.
-func NewPBFileReader(ctx context.Context, n *mdag.ProtoNode, pb *ftpb.Data, serv ipld.NodeGetter) *pbDagReader {
+func NewPBFileReader(ctx context.Context, n *mdag.ProtoNode, pb *ftpb.Data, serv ipld.NodeGetter) *PBDagReader {
 	fctx, cancel := context.WithCancel(ctx)
 	curLinks := getLinkCids(n)
-	return &pbDagReader{
+	return &PBDagReader{
 		node:     n,
 		serv:     serv,
-		buf:      NewBufDagReader(pb.GetData()),
+		buf:      newBufDagReader(pb.GetData()),
 		promises: make([]*ipld.NodePromise, len(curLinks)),
 		links:    curLinks,
 		ctx:      fctx,
@@ -68,7 +68,7 @@ func NewPBFileReader(ctx context.Context, n *mdag.ProtoNode, pb *ftpb.Data, serv
 
 const preloadSize = 10
 
-func (dr *pbDagReader) preloadNextNodes(ctx context.Context) {
+func (dr *PBDagReader) preloadNextNodes(ctx context.Context) {
 	beg := dr.linkPosition
 	end := beg + preloadSize
 	if end >= len(dr.links) {
@@ -82,7 +82,7 @@ func (dr *pbDagReader) preloadNextNodes(ctx context.Context) {
 
 // precalcNextBuf follows the next link in line and loads it from the
 // DAGService, setting the next buffer to read from
-func (dr *pbDagReader) precalcNextBuf(ctx context.Context) error {
+func (dr *PBDagReader) precalcNextBuf(ctx context.Context) error {
 	if dr.buf != nil {
 		dr.buf.Close() // Just to make sure
 		dr.buf = nil
@@ -119,7 +119,7 @@ func (dr *pbDagReader) precalcNextBuf(ctx context.Context) error {
 			dr.buf = NewPBFileReader(dr.ctx, nxt, pb, dr.serv)
 			return nil
 		case ftpb.Data_Raw:
-			dr.buf = NewBufDagReader(pb.GetData())
+			dr.buf = newBufDagReader(pb.GetData())
 			return nil
 		case ftpb.Data_Metadata:
 			return errors.New("shouldnt have had metadata object inside file")
@@ -145,17 +145,17 @@ func getLinkCids(n ipld.Node) []*cid.Cid {
 }
 
 // Size return the total length of the data from the DAG structured file.
-func (dr *pbDagReader) Size() uint64 {
+func (dr *PBDagReader) Size() uint64 {
 	return dr.pbdata.GetFilesize()
 }
 
 // Read reads data from the DAG structured file
-func (dr *pbDagReader) Read(b []byte) (int, error) {
+func (dr *PBDagReader) Read(b []byte) (int, error) {
 	return dr.CtxReadFull(dr.ctx, b)
 }
 
 // CtxReadFull reads data from the DAG structured file
-func (dr *pbDagReader) CtxReadFull(ctx context.Context, b []byte) (int, error) {
+func (dr *PBDagReader) CtxReadFull(ctx context.Context, b []byte) (int, error) {
 	if dr.buf == nil {
 		if err := dr.precalcNextBuf(ctx); err != nil {
 			return 0, err
@@ -189,7 +189,8 @@ func (dr *pbDagReader) CtxReadFull(ctx context.Context, b []byte) (int, error) {
 	}
 }
 
-func (dr *pbDagReader) WriteTo(w io.Writer) (int64, error) {
+// WriteTo writes to the given writer.
+func (dr *PBDagReader) WriteTo(w io.Writer) (int64, error) {
 	if dr.buf == nil {
 		if err := dr.precalcNextBuf(dr.ctx); err != nil {
 			return 0, err
@@ -220,12 +221,14 @@ func (dr *pbDagReader) WriteTo(w io.Writer) (int64, error) {
 	}
 }
 
-func (dr *pbDagReader) Close() error {
+// Close closes the reader.
+func (dr *PBDagReader) Close() error {
 	dr.cancel()
 	return nil
 }
 
-func (dr *pbDagReader) Offset() int64 {
+// Offset returns the current reader offset
+func (dr *PBDagReader) Offset() int64 {
 	return dr.offset
 }
 
@@ -233,7 +236,7 @@ func (dr *pbDagReader) Offset() int64 {
 // interface matches standard unix seek
 // TODO: check if we can do relative seeks, to reduce the amount of dagreader
 // recreations that need to happen.
-func (dr *pbDagReader) Seek(offset int64, whence int) (int64, error) {
+func (dr *PBDagReader) Seek(offset int64, whence int) (int64, error) {
 	switch whence {
 	case io.SeekStart:
 		if offset < 0 {
@@ -253,17 +256,17 @@ func (dr *pbDagReader) Seek(offset int64, whence int) (int64, error) {
 			if dr.buf != nil {
 				dr.buf.Close()
 			}
-			dr.buf = NewBufDagReader(pb.GetData()[offset:])
+			dr.buf = newBufDagReader(pb.GetData()[offset:])
 
 			// start reading links from the beginning
 			dr.linkPosition = 0
 			dr.offset = offset
 			return offset, nil
-		} else {
-			// skip past root block data
-			left -= int64(len(pb.Data))
 		}
 
+		// skip past root block data
+		left -= int64(len(pb.Data))
+
 		// iterate through links and find where we need to be
 		for i := 0; i < len(pb.Blocksizes); i++ {
 			if pb.Blocksizes[i] > uint64(left) {