Function updatePrometheusDoc

scripts/metricsdocgen/main.go:141–189

(doc []byte, metricFamilies []*dto.MetricFamily)

}

func updatePrometheusDoc(doc []byte, metricFamilies []*dto.MetricFamily) ([]byte, error) {
	i := bytes.Index(doc, generatorPrefix)
	if i < 0 {
		return nil, xerrors.New("generator prefix tag not found")
	}
	tableStartIndex := i + len(generatorPrefix) + 1

	j := bytes.Index(doc[tableStartIndex:], generatorSuffix)
	if j < 0 {
		return nil, xerrors.New("generator suffix tag not found")
	}
	tableEndIndex := tableStartIndex + j

	var buffer bytes.Buffer
	_, _ = buffer.Write(doc[:tableStartIndex])
	_ = buffer.WriteByte('\n')

	_, _ = buffer.WriteString("| Name | Type | Description | Labels |\n")
	_, _ = buffer.WriteString("| - | - | - | - |\n")
	for _, mf := range metricFamilies {
		_, _ = buffer.WriteString("| ")
		_, _ = buffer.Write([]byte("`" + *mf.Name + "`"))
		_, _ = buffer.WriteString(" | ")
		_, _ = buffer.Write([]byte(strings.ToLower(mf.Type.String())))
		_, _ = buffer.WriteString(" | ")
		if mf.Help != nil {
			_, _ = buffer.Write([]byte(*mf.Help))
		}
		_, _ = buffer.WriteString(" | ")

		labels := map[string]struct{}{}
		metrics := mf.GetMetric()
		for _, m := range metrics {
			for _, label := range m.Label {
				labels["`"+*label.Name+"`"] = struct{}{}
			}
		}

		if len(labels) > 0 {
			_, _ = buffer.WriteString(strings.Join(maps.SortedKeys(labels), " "))
		}

		_, _ = buffer.WriteString(" |\n")
	}

	_ = buffer.WriteByte('\n')
	_, _ = buffer.Write(doc[tableEndIndex:])
	return buffer.Bytes(), nil
}

func writePrometheusDoc(doc []byte) error {
	return atomicwrite.File(prometheusDocFile, doc)