hashicorp/terraform · error

unrecognized type: %s

Error message

unrecognized type: %s

What it means

Returned by pathFromFlatmapKeyValue (paths.go:148) in the default branch of its type switch — the cty.Type matched none of primitive, object, tuple, map, list, or set. This indicates an unrecognized or unsupported type in the flatmap-key-to-path conversion path, such as a capsule type or a dynamic pseudo-type that was not resolved.

Source

Thrown at internal/configs/hcl2shim/paths.go:148

func pathFromFlatmapKeyValue(key string, ty cty.Type) (cty.Path, error) {
	var path cty.Path
	var err error

	switch {
	case ty.IsPrimitiveType():
		err = fmt.Errorf("invalid step %q with type %#v", key, ty)
	case ty.IsObjectType():
		path, err = pathFromFlatmapKeyObject(key, ty.AttributeTypes())
	case ty.IsTupleType():
		path, err = pathFromFlatmapKeyTuple(key, ty.TupleElementTypes())
	case ty.IsMapType():
		path, err = pathFromFlatmapKeyMap(key, ty)
	case ty.IsListType():
		path, err = pathFromFlatmapKeyList(key, ty)
	case ty.IsSetType():
		path, err = pathFromFlatmapKeySet(key, ty)
	default:
		err = fmt.Errorf("unrecognized type: %s", ty.FriendlyName())
	}

	if err != nil {
		return path, err
	}

	return path, nil
}

func pathFromFlatmapKeyTuple(key string, etys []cty.Type) (cty.Path, error) {
	var path cty.Path
	var err error

	k, rest := pathSplit(key)

	// we don't need to convert the index keys to paths
	if k == "#" {
		return path, nil

View on GitHub (pinned to c9def3e214)

Solutions

1. Print ty.FriendlyName() (shown in the message) and confirm the type is one flatmap paths can handle.
2. Resolve any DynamicPseudoType to a concrete type before it reaches the path shim.
3. Replace unsupported capsule types in schema attributes with standard cty kinds, or handle them in a dedicated code path.
4. Validate provider schemas with InternalValidate in tests to catch exotic types early.

Example fix

// before — attr Type set to a custom capsule type
attr := &configschema.Attribute{Type: myCapsule}

// after — use a standard cty kind
attr := &configschema.Attribute{Type: cty.Map(cty.String)}

// Only the 6 standard kinds are path-navigable
func isPathNavigable(ty cty.Type) bool {
    return ty.IsPrimitiveType() || ty.IsObjectType() || ty.IsTupleType() ||
        ty.IsMapType() || ty.IsListType() || ty.IsSetType()
}

func isPathNavigable(ty cty.Type) bool {
    return ty.IsPrimitiveType() || ty.IsObjectType() || ty.IsTupleType() ||
        ty.IsMapType() || ty.IsListType() || ty.IsSetType()
}

When it happens

Trigger: Calling requiresReplacePath / pathFromFlatmapKeyValue with a cty.Type that is not one of the six standard structural/primitive kinds. Reached when a schema attribute's type is a capsule or unresolved dynamic reaching the path-shim layer.

Common situations: Custom cty capsule types leaking into schema attributes. cty.DynamicPseudoType used where a concrete type was expected. Internally inconsistent type descriptors from a buggy provider schema.

Related errors

• Failed to marshal index step key %#v: %s
• cannot decode %s from flatmap
• [%s] %s
• attribute %q not found
• invalid step %q with type %#v

AI-assisted analysis of hashicorp/terraform@c9def3e214 (2026-08-07). Data as JSON: /api/errors/edc3daffc14dd628. Report an issue: GitHub.