cmds/get: fix context timeout problem

Get had a random timeout of 60s. This commit fixes that, wiring
up our contexts correctly.

License: MIT
Signed-off-by: Juan Batiz-Benet <juan@benet.ai>

core/commands/get.go

@@ -120,8 +120,7 @@ may also specify the level of compression by specifying '-l=<1-9>'.
 			bar.Start()
 			defer bar.Finish()
 
-			_, err = io.Copy(file, pbReader)
-			if err != nil {
+			if _, err := io.Copy(file, pbReader); err != nil {
 				res.SetError(err, cmds.ErrNormal)
 				return
 			}
@@ -140,10 +139,8 @@ may also specify the level of compression by specifying '-l=<1-9>'.
 
 		bar.Start()
 		defer bar.Finish()
-
 		extractor := &tar.Extractor{outPath}
-		err = extractor.Extract(reader)
-		if err != nil {
+		if err := extractor.Extract(reader); err != nil {
 			res.SetError(err, cmds.ErrNormal)
 		}
 	},
@@ -169,7 +166,7 @@ func get(ctx context.Context, node *core.IpfsNode, p path.Path, compression int)
 		return nil, err
 	}
 
-	return utar.NewReader(p, node.DAG, dagnode, compression)
+	return utar.NewReader(ctx, p, node.DAG, dagnode, compression)
 }
 
 // getZip is equivalent to `ipfs getdag $hash | gzip`

thirdparty/tar/extractor.go

@@ -39,15 +39,13 @@ func (te *Extractor) Extract(reader io.Reader) error {
 		}
 
 		if header.Typeflag == tar.TypeDir {
-			err = te.extractDir(header, i, exists)
-			if err != nil {
+			if err := te.extractDir(header, i, exists); err != nil {
 				return err
 			}
 			continue
 		}
 
-		err = te.extractFile(header, tarReader, i, exists, pathIsDir)
-		if err != nil {
+		if err := te.extractFile(header, tarReader, i, exists, pathIsDir); err != nil {
 			return err
 		}
 	}

unixfs/tar/reader.go

@@ -9,7 +9,7 @@ import (
 	"time"
 
 	proto "github.com/ipfs/go-ipfs/Godeps/_workspace/src/github.com/gogo/protobuf/proto"
-	"github.com/ipfs/go-ipfs/Godeps/_workspace/src/golang.org/x/net/context"
+	cxt "github.com/ipfs/go-ipfs/Godeps/_workspace/src/golang.org/x/net/context"
 
 	mdag "github.com/ipfs/go-ipfs/merkledag"
 	path "github.com/ipfs/go-ipfs/path"
@@ -28,7 +28,7 @@ type Reader struct {
 	err        error
 }
 
-func NewReader(path path.Path, dag mdag.DAGService, dagnode *mdag.Node, compression int) (*Reader, error) {
+func NewReader(ctx cxt.Context, path path.Path, dag mdag.DAGService, dagnode *mdag.Node, compression int) (*Reader, error) {
 
 	reader := &Reader{
 		signalChan: make(chan struct{}),
@@ -49,12 +49,11 @@ func NewReader(path path.Path, dag mdag.DAGService, dagnode *mdag.Node, compress
 	// writeToBuf will write the data to the buffer, and will signal when there
 	// is new data to read
 	_, filename := gopath.Split(path.String())
-	go reader.writeToBuf(dagnode, filename, 0)
-
+	go reader.writeToBuf(ctx, dagnode, filename, 0)
 	return reader, nil
 }
 
-func (r *Reader) writeToBuf(dagnode *mdag.Node, path string, depth int) {
+func (r *Reader) writeToBuf(ctx cxt.Context, dagnode *mdag.Node, path string, depth int) {
 	pb := new(upb.Data)
 	err := proto.Unmarshal(dagnode.Data, pb)
 	if err != nil {
@@ -80,16 +79,13 @@ func (r *Reader) writeToBuf(dagnode *mdag.Node, path string, depth int) {
 		}
 		r.flush()
 
-		ctx, cancel := context.WithTimeout(context.TODO(), time.Second*60)
-		defer cancel()
-
 		for i, ng := range r.dag.GetDAG(ctx, dagnode) {
 			childNode, err := ng.Get(ctx)
 			if err != nil {
 				r.emitError(err)
 				return
 			}
-			r.writeToBuf(childNode, gopath.Join(path, dagnode.Links[i].Name), depth+1)
+			r.writeToBuf(ctx, childNode, gopath.Join(path, dagnode.Links[i].Name), depth+1)
 		}
 		return
 	}
@@ -108,7 +104,7 @@ func (r *Reader) writeToBuf(dagnode *mdag.Node, path string, depth int) {
 	}
 	r.flush()
 
-	reader, err := uio.NewDagReader(context.TODO(), dagnode, r.dag)
+	reader, err := uio.NewDagReader(ctx, dagnode, r.dag)
 	if err != nil {
 		r.emitError(err)
 		return