refactor: use command output in status output (#1314)

Signed-off-by: Billy Zha <jinzha1@microsoft.com>

cmd/oras/internal/display/handler.go

@@ -32,7 +32,7 @@ func NewPushHandler(format string, tty *os.File, out io.Writer, verbose bool) (s
 	if tty != nil {
 		statusHandler = status.NewTTYPushHandler(tty)
 	} else if format == "" {
-		statusHandler = status.NewTextPushHandler(verbose)
+		statusHandler = status.NewTextPushHandler(out, verbose)
 	} else {
 		statusHandler = status.NewDiscardHandler()
 	}
@@ -56,7 +56,7 @@ func NewAttachHandler(format string, tty *os.File, out io.Writer, verbose bool)
 	if tty != nil {
 		statusHandler = status.NewTTYAttachHandler(tty)
 	} else if format == "" {
-		statusHandler = status.NewTextAttachHandler(verbose)
+		statusHandler = status.NewTextAttachHandler(out, verbose)
 	} else {
 		statusHandler = status.NewDiscardHandler()
 	}

cmd/oras/internal/display/status/print.go

@@ -19,6 +19,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"os"
 	"sync"
 
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
@@ -27,28 +28,30 @@ import (
 	"oras.land/oras-go/v2/registry"
 )
 
-var printLock sync.Mutex
-
 // PrintFunc is the function type returned by StatusPrinter.
 type PrintFunc func(ocispec.Descriptor) error
 
-// Print objects to display concurrent-safely.
-func Print(a ...any) error {
-	printLock.Lock()
-	defer printLock.Unlock()
-	_, err := fmt.Println(a...)
-	return err
+// Printer prints for status handlers.
+type Printer struct {
+	out  io.Writer
+	lock sync.Mutex
 }
 
-// StatusPrinter returns a tracking function for transfer status.
-func StatusPrinter(status string, verbose bool) PrintFunc {
-	return func(desc ocispec.Descriptor) error {
-		return PrintStatus(desc, status, verbose)
-	}
+// NewPrinter creates a new Printer.
+func NewPrinter(out io.Writer) *Printer {
+	return &Printer{out: out}
+}
+
+// Println prints objects concurrent-safely with newline.
+func (p *Printer) Println(a ...any) error {
+	p.lock.Lock()
+	defer p.lock.Unlock()
+	_, err := fmt.Fprintln(p.out, a...)
+	return err
 }
 
 // PrintStatus prints transfer status.
-func PrintStatus(desc ocispec.Descriptor, status string, verbose bool) error {
+func (p *Printer) PrintStatus(desc ocispec.Descriptor, status string, verbose bool) error {
 	name, ok := desc.Annotations[ocispec.AnnotationTitle]
 	if !ok {
 		// no status for unnamed content
@@ -57,7 +60,14 @@ func PrintStatus(desc ocispec.Descriptor, status string, verbose bool) error {
 		}
 		name = desc.MediaType
 	}
-	return Print(status, ShortDigest(desc), name)
+	return p.Println(status, ShortDigest(desc), name)
+}
+
+// StatusPrinter returns a tracking function for transfer status.
+func (p *Printer) StatusPrinter(status string, verbose bool) PrintFunc {
+	return func(desc ocispec.Descriptor) error {
+		return p.PrintStatus(desc, status, verbose)
+	}
 }
 
 // PrintSuccessorStatus prints transfer status of successors.
@@ -78,18 +88,6 @@ func PrintSuccessorStatus(ctx context.Context, desc ocispec.Descriptor, fetcher
 	return nil
 }
 
-// NewTagStatusPrinter creates a wrapper type for printing tag status.
-func NewTagStatusPrinter(target oras.Target) oras.Target {
-	if repo, ok := target.(registry.Repository); ok {
-		return &tagManifestStatusForRepo{
-			Repository: repo,
-		}
-	}
-	return &tagManifestStatusForTarget{
-		Target: target,
-	}
-}
-
 // NewTagStatusHintPrinter creates a wrapper type for printing
 // tag status and hint.
 func NewTagStatusHintPrinter(target oras.Target, refPrefix string) oras.Target {
@@ -148,3 +146,34 @@ func (p *tagManifestStatusForTarget) Tag(ctx context.Context, desc ocispec.Descr
 	}
 	return Print("Tagged", reference)
 }
+
+// NewTagStatusPrinter creates a wrapper type for printing tag status.
+func NewTagStatusPrinter(target oras.Target) oras.Target {
+	if repo, ok := target.(registry.Repository); ok {
+		return &tagManifestStatusForRepo{
+			Repository: repo,
+		}
+	}
+	return &tagManifestStatusForTarget{
+		Target: target,
+	}
+}
+
+// printer is used by the code being deprecated. Related functions should be
+// removed when no-longer referenced.
+var printer = NewPrinter(os.Stdout)
+
+// Print objects to display concurrent-safely.
+func Print(a ...any) error {
+	return printer.Println(a...)
+}
+
+// StatusPrinter returns a tracking function for transfer status.
+func StatusPrinter(status string, verbose bool) PrintFunc {
+	return printer.StatusPrinter(status, verbose)
+}
+
+// PrintStatus prints transfer status.
+func PrintStatus(desc ocispec.Descriptor, status string, verbose bool) error {
+	return printer.PrintStatus(desc, status, verbose)
+}

cmd/oras/internal/display/status/text.go

@@ -17,7 +17,7 @@ package status
 
 import (
 	"context"
-	"fmt"
+	"io"
 	"sync"
 
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
@@ -28,12 +28,14 @@ import (
 // TextPushHandler handles text status output for push events.
 type TextPushHandler struct {
 	verbose bool
+	printer *Printer
 }
 
 // NewTextPushHandler returns a new handler for push command.
-func NewTextPushHandler(verbose bool) PushHandler {
+func NewTextPushHandler(out io.Writer, verbose bool) PushHandler {
 	return &TextPushHandler{
 		verbose: verbose,
+		printer: NewPrinter(out),
 	}
 }
 
@@ -42,14 +44,12 @@ func (ph *TextPushHandler) OnFileLoading(name string) error {
 	if !ph.verbose {
 		return nil
 	}
-	_, err := fmt.Println("Preparing", name)
-	return err
+	return ph.printer.Println("Preparing", name)
 }
 
 // OnEmptyArtifact is called when an empty artifact is being uploaded.
 func (ph *TextPushHandler) OnEmptyArtifact() error {
-	_, err := fmt.Println("Uploading empty artifact")
-	return err
+	return ph.printer.Println("Uploading empty artifact")
 }
 
 // TrackTarget returns a tracked target.
@@ -68,21 +68,21 @@ func (ph *TextPushHandler) UpdateCopyOptions(opts *oras.CopyGraphOptions, fetche
 	committed := &sync.Map{}
 	opts.OnCopySkipped = func(ctx context.Context, desc ocispec.Descriptor) error {
 		committed.Store(desc.Digest.String(), desc.Annotations[ocispec.AnnotationTitle])
-		return PrintStatus(desc, promptExists, ph.verbose)
+		return ph.printer.PrintStatus(desc, promptExists, ph.verbose)
 	}
 	opts.PreCopy = func(ctx context.Context, desc ocispec.Descriptor) error {
-		return PrintStatus(desc, promptUploading, ph.verbose)
+		return ph.printer.PrintStatus(desc, promptUploading, ph.verbose)
 	}
 	opts.PostCopy = func(ctx context.Context, desc ocispec.Descriptor) error {
 		committed.Store(desc.Digest.String(), desc.Annotations[ocispec.AnnotationTitle])
-		if err := PrintSuccessorStatus(ctx, desc, fetcher, committed, StatusPrinter(promptSkipped, ph.verbose)); err != nil {
+		if err := PrintSuccessorStatus(ctx, desc, fetcher, committed, ph.printer.StatusPrinter(promptSkipped, ph.verbose)); err != nil {
 			return err
 		}
-		return PrintStatus(desc, promptUploaded, ph.verbose)
+		return ph.printer.PrintStatus(desc, promptUploaded, ph.verbose)
 	}
 }
 
 // NewTextAttachHandler returns a new handler for attach command.
-func NewTextAttachHandler(verbose bool) AttachHandler {
-	return NewTextPushHandler(verbose)
+func NewTextAttachHandler(out io.Writer, verbose bool) AttachHandler {
+	return NewTextPushHandler(out, verbose)
 }