refactor: Create tracked reader interface

Signed-off-by: Terry Howe <terrylhowe@gmail.com>

cmd/oras/internal/display/status/track/reader.go

@@ -23,6 +23,14 @@ import (
 	"oras.land/oras/cmd/oras/internal/display/status/progress"
 )
 
+type Reader interface {
+	io.Reader
+	Done()
+	Close()
+	Start()
+	StopManager()
+}
+
 type reader struct {
 	base         io.Reader
 	offset       int64
@@ -34,28 +42,20 @@ type reader struct {
 }
 
 // NewReader returns a new reader with tracked progress.
-func NewReader(r io.Reader, descriptor ocispec.Descriptor, actionPrompt string, donePrompt string, tty *os.File) (*reader, error) {
+func NewReader(r io.Reader, descriptor ocispec.Descriptor, actionPrompt string, donePrompt string, tty *os.File) (Reader, error) {
 	manager, err := progress.NewManager(tty)
 	if err != nil {
 		return nil, err
 	}
-	return managedReader(r, descriptor, manager, actionPrompt, donePrompt)
-}
-
-func managedReader(r io.Reader, descriptor ocispec.Descriptor, manager progress.Manager, actionPrompt string, donePrompt string) (*reader, error) {
-	messenger, err := manager.Add()
-	if err != nil {
-		return nil, err
-	}
-
-	return &reader{
+	tr := reader{
 		base:         r,
 		descriptor:   descriptor,
 		actionPrompt: actionPrompt,
 		donePrompt:   donePrompt,
 		manager:      manager,
-		messenger:    messenger,
-	}, nil
+	}
+	tr.messenger, err = manager.Add()
+	return &tr, err
 }
 
 // StopManager stops the messenger channel and related manager.

cmd/oras/internal/display/status/track/target.go

@@ -35,6 +35,7 @@ type GraphTarget interface {
 
 type graphTarget struct {
 	oras.GraphTarget
+	tty          *os.File
 	manager      progress.Manager
 	actionPrompt string
 	donePrompt   string
@@ -52,6 +53,7 @@ func NewTarget(t oras.GraphTarget, actionPrompt, donePrompt string, tty *os.File
 	}
 	gt := &graphTarget{
 		GraphTarget:  t,
+		tty:          tty,
 		manager:      manager,
 		actionPrompt: actionPrompt,
 		donePrompt:   donePrompt,
@@ -74,7 +76,7 @@ func (t *graphTarget) Mount(ctx context.Context, desc ocispec.Descriptor, fromRe
 
 // Push pushes the content to the base oras.GraphTarget with tracking.
 func (t *graphTarget) Push(ctx context.Context, expected ocispec.Descriptor, content io.Reader) error {
-	r, err := managedReader(content, expected, t.manager, t.actionPrompt, t.donePrompt)
+	r, err := NewReader(content, expected, t.actionPrompt, t.donePrompt, t.tty)
 	if err != nil {
 		return err
 	}
@@ -89,7 +91,7 @@ func (t *graphTarget) Push(ctx context.Context, expected ocispec.Descriptor, con
 
 // PushReference pushes the content to the base oras.GraphTarget with tracking.
 func (rgt *referenceGraphTarget) PushReference(ctx context.Context, expected ocispec.Descriptor, content io.Reader, reference string) error {
-	r, err := managedReader(content, expected, rgt.manager, rgt.actionPrompt, rgt.donePrompt)
+	r, err := NewReader(content, expected, rgt.actionPrompt, rgt.donePrompt, rgt.tty)
 	if err != nil {
 		return err
 	}