coreapi unixfs: remove Cat, use sessions

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>

core/commands/cat.go

@@ -10,6 +10,7 @@ import (
 	"github.com/ipfs/go-ipfs/core/coreapi/interface"
 
 	cmds "gx/ipfs/QmRRovo1DE6i5cMjCbf19mQCSuszF6SKwdZNUMS7MtBnH1/go-ipfs-cmds"
+	"gx/ipfs/QmZMWMvWMVKCbHetJ4RgndbuEF1io2UpUxwQwtNjtYPzSC/go-ipfs-files"
 	"gx/ipfs/Qmde5VP1qUkyQXKCfmEUA7bP64V2HAptbJ7phuPp7jXWwg/go-ipfs-cmdkit"
 )
 
@@ -123,6 +124,12 @@ var CatCmd = &cmds.Command{
 	},
 }
 
+type catFile interface {
+	files.SizeFile
+
+	io.Seeker
+}
+
 func cat(ctx context.Context, api iface.CoreAPI, paths []string, offset int64, max int64) ([]io.Reader, uint64, error) {
 	readers := make([]io.Reader, 0, len(paths))
 	length := uint64(0)
@@ -135,32 +142,46 @@ func cat(ctx context.Context, api iface.CoreAPI, paths []string, offset int64, m
 			return nil, 0, err
 		}
 
-		read, err := api.Unixfs().Cat(ctx, fpath)
+		f, err := api.Unixfs().Get(ctx, fpath)
+		if err != nil {
+			return nil, 0, err
+		}
+
+		file := f.(catFile)
+
+		fsize, err := file.Size()
 		if err != nil {
 			return nil, 0, err
 		}
-		if offset > int64(read.Size()) {
-			offset = offset - int64(read.Size())
+
+		if offset > fsize {
+			offset = offset - fsize
 			continue
 		}
-		count, err := read.Seek(offset, io.SeekStart)
+
+		count, err := file.Seek(offset, io.SeekStart)
 		if err != nil {
 			return nil, 0, err
 		}
 		offset = 0
 
-		size := uint64(read.Size() - uint64(count))
+		fsize, err = file.Size()
+		if err != nil {
+			return nil, 0, err
+		}
+
+		size := uint64(fsize - count)
 		length += size
 		if max > 0 && length >= uint64(max) {
-			var r io.Reader = read
+			var r io.Reader = file
 			if overshoot := int64(length - uint64(max)); overshoot != 0 {
-				r = io.LimitReader(read, int64(size)-overshoot)
+				r = io.LimitReader(file, int64(size)-overshoot)
 				length = uint64(max)
 			}
 			readers = append(readers, r)
 			break
 		}
-		readers = append(readers, read)
+		readers = append(readers, file)
 	}
 	return readers, length, nil
 }

core/coreapi/interface/unixfs.go

@@ -31,10 +31,6 @@ type UnixfsAPI interface {
 	// to operations performed on the returned file
 	Get(context.Context, Path) (files.File, error)
 
-	// Cat returns a reader for the file
-	// TODO: Remove in favour of Get (if we use Get on a file we still have reader directly, so..)
-	Cat(context.Context, Path) (Reader, error)
-
 	// Ls returns the list of links in a directory
 	Ls(context.Context, Path) ([]*ipld.Link, error)
 }

core/coreapi/unixfs.go

@@ -139,25 +139,8 @@ func (api *UnixfsAPI) Get(ctx context.Context, p coreiface.Path) (files.File, er
 		return nil, err
 	}
 
-	return newUnixfsFile(ctx, api.node.DAG, nd, "", nil)
-}
-
-// Cat returns the data contained by an IPFS or IPNS object(s) at path `p`.
-func (api *UnixfsAPI) Cat(ctx context.Context, p coreiface.Path) (coreiface.Reader, error) {
-	dget := api.node.DAG // TODO: use a session here once routing perf issues are resolved
-
-	dagnode, err := api.core().ResolveNode(ctx, p)
-	if err != nil {
-		return nil, err
-	}
-
-	r, err := uio.NewDagReader(ctx, dagnode, dget)
-	if err == uio.ErrIsDir {
-		return nil, coreiface.ErrIsDir
-	} else if err != nil {
-		return nil, err
-	}
-	return r, nil
+	ses := dag.NewReadOnlyDagService(dag.NewSession(ctx, api.node.DAG))
+	return newUnixfsFile(ctx, ses, nd, "", nil)
 }
 
 // Ls returns the contents of an IPFS or IPNS object(s) at path p, with the format:

core/coreapi/unixfs_test.go

@@ -623,7 +623,7 @@ func TestAddHashOnly(t *testing.T) {
 	}
 }
 
-func TestCatEmptyFile(t *testing.T) {
+func TestGetEmptyFile(t *testing.T) {
 	ctx := context.Background()
 	node, api, err := makeAPI(ctx)
 	if err != nil {
@@ -640,7 +640,7 @@ func TestCatEmptyFile(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	r, err := api.Unixfs().Cat(ctx, emptyFilePath)
+	r, err := api.Unixfs().Get(ctx, emptyFilePath)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -655,7 +655,7 @@ func TestCatEmptyFile(t *testing.T) {
 	}
 }
 
-func TestCatDir(t *testing.T) {
+func TestGetDir(t *testing.T) {
 	ctx := context.Background()
 	node, api, err := makeAPI(ctx)
 	if err != nil {
@@ -677,13 +677,18 @@ func TestCatDir(t *testing.T) {
 		t.Fatalf("expected path %s, got: %s", emptyDir.Cid(), p.String())
 	}
 
-	_, err = api.Unixfs().Cat(ctx, coreiface.IpfsPath(emptyDir.Cid()))
-	if err != coreiface.ErrIsDir {
+	r, err := api.Unixfs().Get(ctx, coreiface.IpfsPath(emptyDir.Cid()))
+	if err != nil {
+		t.Error(err)
+	}
+
+	_, err = r.Read(make([]byte, 2))
+	if err != files.ErrNotReader {
 		t.Fatalf("expected ErrIsDir, got: %s", err)
 	}
 }
 
-func TestCatNonUnixfs(t *testing.T) {
+func TestGetNonUnixfs(t *testing.T) {
 	ctx := context.Background()
 	node, api, err := makeAPI(ctx)
 	if err != nil {
@@ -696,7 +701,7 @@ func TestCatNonUnixfs(t *testing.T) {
 		t.Error(err)
 	}
 
-	_, err = api.Unixfs().Cat(ctx, coreiface.IpfsPath(nd.Cid()))
+	_, err = api.Unixfs().Get(ctx, coreiface.IpfsPath(nd.Cid()))
 	if !strings.Contains(err.Error(), "proto: required field") {
 		t.Fatalf("expected protobuf error, got: %s", err)
 	}
@@ -713,7 +718,7 @@ func TestCatOffline(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	_, err = api.Unixfs().Cat(ctx, p)
+	_, err = api.Unixfs().Get(ctx, p)
 	if err != coreiface.ErrOffline {
 		t.Fatalf("expected ErrOffline, got: %s", err)
 	}

core/corehttp/gateway_handler.go

@@ -178,14 +178,12 @@ func (i *gatewayHandler) getOrHeadHandler(ctx context.Context, w http.ResponseWr
 		return
 	}
 
-	dr, err := i.api.Unixfs().Cat(ctx, resolvedPath)
-	dir := false
+	dr, err := i.api.Unixfs().Get(ctx, resolvedPath)
+	dir := dr.IsDirectory()
 	switch err {
 	case nil:
 		// Cat() worked
 		defer dr.Close()
-	case coreiface.ErrIsDir:
-		dir = true
 	default:
 		webError(w, "ipfs cat "+escapedURLPath, err, http.StatusNotFound)
 		return
@@ -270,7 +268,7 @@ func (i *gatewayHandler) getOrHeadHandler(ctx context.Context, w http.ResponseWr
 		} else {
 			name = getFilename(urlPath)
 		}
-		i.serveFile(w, r, name, modtime, dr)
+		i.serveFile(w, r, name, modtime, dr.(io.ReadSeeker))
 		return
 	}
 
@@ -297,7 +295,7 @@ func (i *gatewayHandler) getOrHeadHandler(ctx context.Context, w http.ResponseWr
 			return
 		}
 
-		dr, err := i.api.Unixfs().Cat(ctx, coreiface.IpfsPath(ixnd.Cid()))
+		dr, err := i.api.Unixfs().Get(ctx, coreiface.IpfsPath(ixnd.Cid()))
 		if err != nil {
 			internalWebError(w, err)
 			return
@@ -305,7 +303,7 @@ func (i *gatewayHandler) getOrHeadHandler(ctx context.Context, w http.ResponseWr
 		defer dr.Close()
 
 		// write to request
-		http.ServeContent(w, r, "index.html", modtime, dr)
+		http.ServeContent(w, r, "index.html", modtime, dr.(io.ReadSeeker))
 		return
 	default:
 		internalWebError(w, err)

fuse/readonly/ipfs_test.go

@@ -175,7 +175,7 @@ func TestIpfsStressRead(t *testing.T) {
 					errs <- err
 				}
 
-				read, err := api.Unixfs().Cat(nd.Context(), item)
+				read, err := api.Unixfs().Get(nd.Context(), item)
 				if err != nil {
 					errs <- err
 				}

test/integration/addcat_test.go

@@ -147,7 +147,7 @@ func DirectAddCat(data []byte, conf testutil.LatencyConfig) error {
 		return err
 	}
 
-	readerCatted, err := catterApi.Unixfs().Cat(ctx, ap)
+	readerCatted, err := catterApi.Unixfs().Get(ctx, ap)
 	if err != nil {
 		return err
 	}

test/integration/bench_cat_test.go

@@ -94,7 +94,7 @@ func benchCat(b *testing.B, data []byte, conf testutil.LatencyConfig) error {
 	}
 
 	b.StartTimer()
-	readerCatted, err := catterApi.Unixfs().Cat(ctx, ap)
+	readerCatted, err := catterApi.Unixfs().Get(ctx, ap)
 	if err != nil {
 		return err
 	}

test/integration/three_legged_cat_test.go

@@ -126,7 +126,7 @@ func RunThreeLeggedCat(data []byte, conf testutil.LatencyConfig) error {
 		return err
 	}
 
-	readerCatted, err := catterApi.Unixfs().Cat(ctx, ap)
+	readerCatted, err := catterApi.Unixfs().Get(ctx, ap)
 	if err != nil {
 		return err
 	}