Method processFile

collector/textfile.go:288–315

processFile processes a single file, returning its modification time on success.

(dir, name string, ch chan<- prometheus.Metric)

// processFile processes a single file, returning its modification time on success.
func (c *textFileCollector) processFile(dir, name string, ch chan<- prometheus.Metric) (*time.Time, map[string]*dto.MetricFamily, error) {
	path := filepath.Join(dir, name)
	f, err := os.Open(path)
	if err != nil {
		return nil, nil, fmt.Errorf("failed to open textfile data file %q: %w", path, err)
	}
	defer f.Close()

	parser := expfmt.NewTextParser(model.LegacyValidation)
	families, err := parser.TextToMetricFamilies(f)
	if err != nil {
		return nil, nil, fmt.Errorf("failed to parse textfile data from %q: %w", path, err)
	}

	if hasTimestamps(families) {
		return nil, nil, fmt.Errorf("textfile %q contains unsupported client-side timestamps, skipping entire file", path)
	}

	// Only stat the file once it has been parsed and validated, so that
	// a failure does not appear fresh.
	stat, err := f.Stat()
	if err != nil {
		return nil, families, fmt.Errorf("failed to stat %q: %w", path, err)
	}

	t := stat.ModTime()
	return &t, families, nil
}

// hasTimestamps returns true when metrics contain unsupported timestamps.
func hasTimestamps(parsedFamilies map[string]*dto.MetricFamily) bool {