grafana/k6 · error

length of hash algorithm is less than 4: {v}

Error message

length of hash algorithm is less than 4: {v}

What it means

Error "length of hash algorithm is less than 4: {v}" thrown in grafana/k6.

Source

Thrown at internal/js/modules/k6/webcrypto/jwk.go:97

	exported.Set("kty", JWKOctKeyType)
	exported.Set("ext", key.Extractable)
	exported.Set("key_ops", key.Usages)

	algV, err := extractAlg(key.Algorithm, len(rawKey))
	if err != nil {
		return nil, fmt.Errorf("failed to extract algorithm: %w", err)
	}
	exported.Set("alg", algV)

	return exported, nil
}

func extractAlg(inAlg any, keyLen int) (string, error) {
	switch alg := inAlg.(type) {
	case hasHash:
		v := alg.hash()
		if len(v) < 4 {
			return "", errors.New("length of hash algorithm is less than 4: " + v)
		}
		return "HS" + v[4:], nil
	case hasAlg:
		v := alg.alg()
		if len(v) < 4 {
			return "", errors.New("length of named algorithm is less than 4: " + v)
		}

		return fmt.Sprintf("A%d%s", (8 * keyLen), v[4:]), nil
	default:
		return "", fmt.Errorf("unsupported algorithm: %v", inAlg)
	}
}

// ecJWK represents an EC JWK key.
// It is used to unmarshal ECDSA and ECDH keys to and from JWK format.
type ecJWK struct {
	// Key type

View on GitHub (pinned to 93accf6570)

When it happens

Trigger: Thrown at internal/js/modules/k6/webcrypto/jwk.go:97 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@93accf6570 (2026-08-15). Data as JSON: /api/errors/d921d09d3e2f19be. Report an issue: GitHub.