progress: explicitly fail if tty requested but not available

The NewPrinter function is mostly borrowed from buildkit. However, at
some point, it seems that the implementations drifted.

This patch updates buildx to be more similar in behavior to it's
buildkit counterpart, specifically, it will explicitly fail if a TTY
output is requested using "--progress=tty", but the output is not
available.

To gracefully fallback to plain progress in this scenario,
"--progress=plain" is required.

Signed-off-by: Justin Chadwell <me@jedevc.com>

commands/bake.go

@@ -75,7 +75,10 @@ func runBake(dockerCli command.Cli, targets []string, in bakeOptions) (err error
 
 	ctx2, cancel := context.WithCancel(context.TODO())
 	defer cancel()
-	printer := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, in.progress)
+	printer, err := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, in.progress)
+	if err != nil {
+		return err
+	}
 
 	defer func() {
 		if printer != nil {

commands/build.go

@@ -109,7 +109,7 @@ func runBuild(dockerCli command.Cli, in buildOptions) (err error) {
 		return errors.Errorf("--no-cache and --no-cache-filter cannot currently be used together")
 	}
 
-	if in.quiet && in.progress != "auto" && in.progress != "quiet" {
+	if in.quiet && in.progress != progress.PrinterModeAuto && in.progress != progress.PrinterModeQuiet {
 		return errors.Errorf("progress=%s and quiet cannot be used together", in.progress)
 	} else if in.quiet {
 		in.progress = "quiet"
@@ -284,7 +284,10 @@ func buildTargets(ctx context.Context, dockerCli command.Cli, opts map[string]bu
 	ctx2, cancel := context.WithCancel(context.TODO())
 	defer cancel()
 
-	printer := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, progressMode)
+	printer, err := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, progressMode)
+	if err != nil {
+		return "", nil, err
+	}
 
 	var mu sync.Mutex
 	var idx int

commands/imagetools/create.go

@@ -182,7 +182,10 @@ func runCreate(dockerCli command.Cli, in createOptions, args []string) error {
 
 	ctx2, cancel := context.WithCancel(context.TODO())
 	defer cancel()
-	printer := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, in.progress)
+	printer, err := progress.NewPrinter(ctx2, os.Stderr, os.Stderr, in.progress)
+	if err != nil {
+		return err
+	}
 
 	eg, _ := errgroup.WithContext(ctx)
 	pw := progress.WithPrefix(printer, "internal", true)

commands/util.go

@@ -460,7 +460,10 @@ func boot(ctx context.Context, ngi *nginfo) (bool, error) {
 		return false, nil
 	}
 
-	printer := progress.NewPrinter(context.TODO(), os.Stderr, os.Stderr, "auto")
+	printer, err := progress.NewPrinter(context.TODO(), os.Stderr, os.Stderr, progress.PrinterModeAuto)
+	if err != nil {
+		return false, err
+	}
 
 	baseCtx := ctx
 	eg, _ := errgroup.WithContext(ctx)
@@ -477,7 +480,7 @@ func boot(ctx context.Context, ngi *nginfo) (bool, error) {
 		}(idx)
 	}
 
-	err := eg.Wait()
+	err = eg.Wait()
 	err1 := printer.Wait()
 	if err == nil {
 		err = err1

util/progress/printer.go

@@ -11,6 +11,7 @@ import (
 	"github.com/moby/buildkit/client"
 	"github.com/moby/buildkit/util/progress/progressui"
 	"github.com/opencontainers/go-digest"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -69,7 +70,7 @@ func (p *Printer) ClearLogSource(v interface{}) {
 	}
 }
 
-func NewPrinter(ctx context.Context, w io.Writer, out console.File, mode string) *Printer {
+func NewPrinter(ctx context.Context, w io.Writer, out console.File, mode string) (*Printer, error) {
 	statusCh := make(chan *client.SolveStatus)
 	doneCh := make(chan struct{})
 
@@ -83,7 +84,6 @@ func NewPrinter(ctx context.Context, w io.Writer, out console.File, mode string)
 		mode = v
 	}
 
-	go func() {
 	var c console.Console
 	switch mode {
 	case PrinterModeQuiet:
@@ -91,13 +91,19 @@ func NewPrinter(ctx context.Context, w io.Writer, out console.File, mode string)
 	case PrinterModeAuto, PrinterModeTty:
 		if cons, err := console.ConsoleFromFile(out); err == nil {
 			c = cons
+		} else {
+			if mode == PrinterModeTty {
+				return nil, errors.Wrap(err, "failed to get console")
+			}
 		}
 	}
+
+	go func() {
 		resumeLogs := logutil.Pause(logrus.StandardLogger())
 		// not using shared context to not disrupt display but let is finish reporting errors
 		pw.warnings, pw.err = progressui.DisplaySolveStatus(ctx, "", c, w, statusCh)
 		resumeLogs()
 		close(doneCh)
 	}()
-	return pw
+	return pw, nil
 }