feat: support the progress writer for pull operation (#171)

Signed-off-by: chlins <[email protected]>

Author: chlins

internal/pb/pb.go

@@ -19,6 +19,7 @@ package pb
 import (
 	"fmt"
 	"io"
+	"os"
 	"sync"
 	"time"
 
@@ -46,9 +47,24 @@ type progressBar struct {
 }
 
 // NewProgressBar creates a new progress bar.
-func NewProgressBar() *ProgressBar {
+func NewProgressBar(writers ...io.Writer) *ProgressBar {
+	opts := []mpbv8.ContainerOption{
+		mpbv8.WithAutoRefresh(),
+		mpbv8.WithWidth(60),
+		mpbv8.WithRefreshRate(300 * time.Millisecond),
+	}
+
+	// If no writer specified, use stdout.
+	if len(writers) == 0 {
+		opts = append(opts, mpbv8.WithOutput(os.Stdout))
+	} else if len(writers) == 1 {
+		opts = append(opts, mpbv8.WithOutput(writers[0]))
+	} else {
+		opts = append(opts, mpbv8.WithOutput(io.MultiWriter(writers...)))
+	}
+
 	return &ProgressBar{
-		mpb:  mpbv8.New(mpbv8.WithWidth(60), mpbv8.WithRefreshRate(300*time.Millisecond)),
+		mpb:  mpbv8.New(opts...),
 		bars: make(map[string]*progressBar),
 	}
 }

pkg/backend/pull.go

@@ -60,7 +60,7 @@ func (b *backend) Pull(ctx context.Context, target string, cfg *config.Pull) err
 	}
 
 	// create the progress bar to track the progress of push.
-	pb := internalpb.NewProgressBar()
+	pb := internalpb.NewProgressBar(cfg.ProgressWriter)
 	pb.Start()
 	defer pb.Stop()
 

pkg/config/pull.go

@@ -18,6 +18,8 @@ package config
 
 import (
 	"fmt"
+	"io"
+	"os"
 
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
@@ -35,6 +37,7 @@ type Pull struct {
 	ExtractDir        string
 	ExtractFromRemote bool
 	Hooks             PullHooks
+	ProgressWriter    io.Writer
 }
 
 func NewPull() *Pull {
@@ -46,6 +49,7 @@ func NewPull() *Pull {
 		ExtractDir:        "",
 		ExtractFromRemote: false,
 		Hooks:             &emptyPullHook{},
+		ProgressWriter:    os.Stdout,
 	}
 }