dagger/dagger · error

engine volume name must not be empty

Error message

engine volume name must not be empty

What it means

ValidateEngineVolumeName rejected an engine volume address because the name portion is the empty string. This is a validation guard: every engine volume reference must carry a non-empty name before it can be parsed into an engine volume ID or config.

Source

Thrown at core/volume.go:81

	return &ast.Type{
		NamedType: "Volume",
		NonNull:   true,
	}
}

func (*Volume) TypeDescription() string {
	return "A filesystem volume that can be mounted into containers."
}

// VolumeContentDigestFromCacheKey returns opt-in cache equivalence evidence.
// It is deliberately not a session-resource handle.
func VolumeContentDigestFromCacheKey(cacheKey string) digest.Digest {
	return hashutil.HashStrings(cacheKey)
}

func ValidateEngineVolumeName(name string) error {
	if name == "" {
		return fmt.Errorf("engine volume name must not be empty")
	}
	if len(name) > engineVolumeMaxPathLength {
		return fmt.Errorf("engine volume name must not exceed %d bytes", engineVolumeMaxPathLength)
	}
	for _, component := range strings.Split(name, "/") {
		if component == "" {
			return fmt.Errorf("engine volume name must use non-empty slash-separated components")
		}
		if len(component) > engineVolumeMaxNameLength {
			return fmt.Errorf("engine volume name component %q must not exceed %d bytes", component, engineVolumeMaxNameLength)
		}
		if component == "fs" {
			return fmt.Errorf("engine volume name component %q is reserved", component)
		}
		for i := range len(component) {
			char := component[i]
			valid := char >= 'A' && char <= 'Z' || char >= 'a' && char <= 'z' || char >= '0' && char <= '9'
			if i > 0 {

View on GitHub (pinned to 82ba2681db)

Solutions

1. Provide a non-empty volume name
2. Check for an unset name variable defaulting to "" in the pipeline

When it happens

Trigger: Thrown at core/volume.go:81 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of dagger/dagger@82ba2681db (2026-09-05). Data as JSON: /api/errors/61af02d658334c26. Report an issue: GitHub.