GoogleContainerTools/skaffold · error

generating tag: %w

Error message

generating tag: %w

What it means

GenerateFullyQualifiedImageName delegates to the configured Tagger's GenerateTag and wraps any tagger failure as 'generating tag:'. This is the generic choke point: every tagger error (bad timezone, git failures, env template problems, hashing errors) surfaces through this wrapper.

Source

Thrown at pkg/skaffold/tag/tag.go:42

	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/schema/latest"
)

// ImageTags maps image names to tags
type ImageTags map[string]string

// Tagger is an interface for tag strategies to be implemented against
type Tagger interface {
	// GenerateTag generates a tag for an artifact.
	GenerateTag(ctx context.Context, image latest.Artifact) (string, error)
}

// GenerateFullyQualifiedImageName resolves the fully qualified image name for an artifact.
// The workingDir is the root directory of the artifact with respect to the Skaffold root,
// and imageName is the base name of the image.
func GenerateFullyQualifiedImageName(ctx context.Context, t Tagger, image latest.Artifact) (string, error) {
	tag, err := t.GenerateTag(ctx, image)
	if err != nil {
		return "", fmt.Errorf("generating tag: %w", err)
	}

	// Tag is already set in imageName
	if tag == "" {
		_, err := docker.ParseReference(image.ImageName)
		if err != nil {
			return "", fmt.Errorf("parsing image name: %w", err)
		}
		return image.ImageName, nil
	}

	fullImageName := fmt.Sprintf("%v:%v", image.ImageName, tag)
	_, err = docker.ParseReference(fullImageName)
	if err != nil {
		return "", fmt.Errorf("parsing image name: %w", err)
	}
	return fullImageName, nil
}

View on GitHub (pinned to a1189de023)

Solutions

1. Read the wrapped cause after 'generating tag:' to identify the actual failing tagger and fix that root cause
2. Verify the tagger config in skaffold.yaml matches your environment (git present, env vars set, timezone valid)
3. Switch to a simpler tagger (e.g. dateTime or sha256) to isolate which tagger prerequisite is failing
4. Run the build locally with the same workspace/CI env to reproduce the tagger failure

tag, err := tag.GenerateFullyQualifiedImageName(ctx, tagger, image)
if err != nil {
    var inner error
    if errors.Unwrap(err) != nil { inner = errors.Unwrap(err) }
    return fmt.Errorf("tagger %T failed: %w (root cause: %v)", tagger, err, inner)
}

When it happens

Trigger: Calling GenerateFullyQualifiedImageName(ctx, tagger, image) where tagger.GenerateTag returns any error — e.g. gitCommit in a non-git workspace, envTemplate with unset vars, dateTime with an invalid timeZone.

Common situations: Debugging skaffold build failures — this wrapping appears in logs above the root cause; CI misconfiguration where the tagger's prerequisites (git repo, env vars) are absent.

Related errors

• bad timezone provided: %q, error: %s
• parsing template: %w
• environment variables missing for template keys
• %q is not a valid git tagger variant
• unable to find git commit: %w

AI-assisted analysis of GoogleContainerTools/skaffold@a1189de023 (2026-09-05). Data as JSON: /api/errors/fdc24ca55a9af4a7. Report an issue: GitHub.