func CollectMetricsFromFile()

in sharedlibraries/configurablemetrics/configurablemetrics.go [90:131]

• 35 lines of code
• 9 McCabe index (conditional complexity)

func CollectMetricsFromFile(ctx context.Context, reader FileReader, path string, metrics []*cmpb.EvalMetric) map[string]string {
	labels := BuildMetricMap(metrics)
	if len(metrics) == 0 {
		return labels
	}

	file, err := reader(path)
	if err != nil {
		log.CtxLogger(ctx).Warnw("Could not read the file", "path", path, "error", err)
		return labels
	}
	defer file.Close()

	metricsByLabel := make(map[string]*cmpb.EvalMetric, len(metrics))
	for _, m := range metrics {
		metricsByLabel[m.GetMetricInfo().GetLabel()] = m
	}

	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		if len(metricsByLabel) == 0 {
			break
		}
		line := strings.TrimSpace(scanner.Text())
		for l, m := range metricsByLabel {
			v, ok := Evaluate(ctx, m, Output{StdOut: line})
			labels[l] = v
			// For a result that evaluates as true, do not attempt to collect this metric again.
			// This assumes that at most one metric will be collected per line scanned.
			if ok {
				delete(metricsByLabel, l)
				break
			}
		}
	}

	if err := scanner.Err(); err != nil {
		log.CtxLogger(ctx).Warnw("Could not read the file", "path", path, "error", err)
	}

	return labels
}