grafana/k6 · error

InvalidConfig

InvalidConfig

Error message

unable to validate threshold expressions; reason: %w

What it means

Wraps an error raised while Thresholds.Validate checks each threshold expression against a metric from the registry. It is a generic wrapper: the real cause (carried by %w) is typically a parse failure of a threshold expression during validation, meaning the expression string does not match the 'aggregation method operator value' grammar.

Source

Thrown at metrics/thresholds.go:247

		t.parsed = parsed
	}

	return nil
}

// ErrInvalidThreshold indicates a threshold is not valid
var ErrInvalidThreshold = errors.New("invalid threshold")

// Validate ensures a threshold definition is consistent with the metric it applies to.
// Given a metric registry and a metric name to apply the expressions too, Validate will
// assert that each threshold expression uses an aggregation method that's supported by the
// provided metric. It returns an error otherwise.
// Note that this function expects the passed in thresholds to have been parsed already, and
// have their Parsed (ThresholdExpression) field already filled.
func (ts *Thresholds) Validate(metricName string, r *Registry) error {
	parsedMetricName, _, err := ParseMetricName(metricName)
	if err != nil {
		parseErr := fmt.Errorf("unable to validate threshold expressions; reason: %w", err)
		return errext.WithExitCodeIfNone(parseErr, exitcodes.InvalidConfig)
	}

	// Obtain the metric the thresholds apply to from the registry.
	// if the metric doesn't exist, then we return an error indicating
	// the InvalidConfig exitcode should be used.
	metric := r.Get(parsedMetricName)
	if metric == nil {
		err := fmt.Errorf("%w defined on %s; reason: no metric name %q found", ErrInvalidThreshold, metricName, metricName)
		return errext.WithExitCodeIfNone(err, exitcodes.InvalidConfig)
	}

	for _, threshold := range ts.Thresholds {
		// Return a digestable error if we attempt to validate a threshold
		// that hasn't been parsed yet.
		if threshold.parsed == nil {
			thresholdExpression, err := parseThresholdExpression(threshold.Source)
			if err != nil {

View on GitHub (pinned to 01ffac6f24)

Solutions

1. Inspect the wrapped error to see which threshold expression failed to parse
2. Rewrite threshold expressions in the form 'method<op>value', e.g. 'p(95)<500' or 'rate<0.01'
3. Use only supported aggregation methods (avg, min, max, med, p(N), count, rate, value)

When it happens

Trigger: Thrown at metrics/thresholds.go:247 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@01ffac6f24 (2026-08-18). Data as JSON: /api/errors/c6d19769ba651798. Report an issue: GitHub.