Refactor metrics doc generator

docs/metrics.md

@@ -1,14 +1,5 @@
-<!--
-	This is an auto-generated file.
-	PLEASE DO NOT EDIT THIS FILE.
-	See "Developing new metrics" below how to generate this file
--->
+# Kubevirt metrics
 
-# KubeVirt metrics
-This document aims to help users that are not familiar with all metrics exposed by different KubeVirt components.
-All metrics documented here are auto-generated by the utility tool `tools/doc-generator` and reflects exactly what is being exposed.
-
-## KubeVirt Metrics List
 ### kubevirt_info
 Version information.
 
@@ -268,6 +259,7 @@ Returns the labels of the persistent volume claims that are used for restoring v
 Amount of active VNC connections, broken down by namespace and vmi name. Type: Gauge.
 
 ## Developing new metrics
-After developing new metrics or changing old ones, please run `make generate` to regenerate this document.
 
-If you feel that the new metric doesn't follow these rules, please change `doc-generator` with your needs.
+All metrics documented here are auto-generated and reflect exactly what is being
+exposed. After developing new metrics or changing old ones please regenerate
+this document.

hack/generate.sh

@@ -140,8 +140,7 @@ ${KUBEVIRT_DIR}/tools/openapispec/openapispec --dump-api-spec-path ${KUBEVIRT_DI
 (cd ${KUBEVIRT_DIR}/tools/doc-generator/ && go_build)
 (
     cd ${KUBEVIRT_DIR}/docs
-    ${KUBEVIRT_DIR}/tools/doc-generator/doc-generator
-    mv newmetrics.md metrics.md
+    ${KUBEVIRT_DIR}/tools/doc-generator/doc-generator >metrics.md
 )
 
 rm -f ${KUBEVIRT_DIR}/manifests/generated/*

tools/doc-generator/BUILD.bazel

@@ -3,6 +3,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
 go_library(
     name = "go_default_library",
     srcs = [
+        "MetricsCollector.go",
         "doc-generator.go",
         "fakeDomainCollector.go",
     ],
@@ -19,7 +20,9 @@ go_library(
         "//pkg/virt-launcher/virtwrap/statsconv:go_default_library",
         "//pkg/virt-launcher/virtwrap/statsconv/util:go_default_library",
         "//staging/src/kubevirt.io/api/core/v1:go_default_library",
+        "//vendor/github.com/machadovilaca/operator-observability/pkg/docs:go_default_library",
         "//vendor/github.com/machadovilaca/operator-observability/pkg/operatormetrics:go_default_library",
+        "//vendor/github.com/machadovilaca/operator-observability/pkg/operatorrules:go_default_library",
         "//vendor/github.com/prometheus/client_golang/prometheus:go_default_library",
         "//vendor/libvirt.org/go/libvirt:go_default_library",
     ],

tools/doc-generator/MetricsCollector.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"sort"
+	"strings"
+
+	domainstats "kubevirt.io/kubevirt/pkg/monitoring/domainstats/prometheus" // import for prometheus metrics
+	_ "kubevirt.io/kubevirt/pkg/virt-controller/watch"
+)
+
+type metric struct {
+	name        string
+	description string
+	mType       string
+}
+
+type metricList []metric
+
+func getMetricsNotIncludeInEndpointByDefault() metricList {
+	metrics := metricList{
+		{
+			name:        domainstats.MigrateVmiDataProcessedMetricName,
+			description: "The total Guest OS data processed and migrated to the new VM.",
+			mType:       "Gauge",
+		},
+		{
+			name:        domainstats.MigrateVmiDataRemainingMetricName,
+			description: "The remaining guest OS data to be migrated to the new VM.",
+			mType:       "Gauge",
+		},
+		{
+			name:        domainstats.MigrateVmiDirtyMemoryRateMetricName,
+			description: "The rate of memory being dirty in the Guest OS.",
+			mType:       "Gauge",
+		},
+		{
+			name:        domainstats.MigrateVmiMemoryTransferRateMetricName,
+			description: "The rate at which the memory is being transferred.",
+			mType:       "Gauge",
+		},
+	}
+
+	return metrics
+}
+
+// Len implements sort.Interface.Len
+func (m metricList) Len() int {
+	return len(m)
+}
+
+// Less implements sort.Interface.Less
+func (m metricList) Less(i, j int) bool {
+	return m[i].name < m[j].name
+}
+
+// Swap implements sort.Interface.Swap
+func (m metricList) Swap(i, j int) {
+	m[i], m[j] = m[j], m[i]
+}
+
+func parseMetricDesc(line string) (string, string) {
+	split := strings.Split(line, " ")
+	name := split[2]
+	split[3] = strings.Title(split[3])
+	description := strings.Join(split[3:], " ")
+	return name, description
+}
+
+func parseMetricType(scan *bufio.Scanner, name string) string {
+	for scan.Scan() {
+		typeLine := scan.Text()
+		if strings.HasPrefix(typeLine, "# TYPE ") {
+			split := strings.Split(typeLine, " ")
+			if split[2] == name {
+				return strings.Title(split[3])
+			}
+		}
+	}
+	return ""
+}
+
+func parseVirtMetrics(r io.Reader, metrics *metricList) error {
+	scan := bufio.NewScanner(r)
+	for scan.Scan() {
+		helpLine := scan.Text()
+		if strings.HasPrefix(helpLine, "# HELP ") {
+			if strings.Contains(helpLine, "kubevirt_") {
+				metName, metDesc := parseMetricDesc(helpLine)
+				metType := parseMetricType(scan, metName)
+				*metrics = append(*metrics, metric{name: metName, description: metDesc, mType: metType})
+			}
+		}
+	}
+
+	if scan.Err() != nil {
+		return fmt.Errorf("failed to parse metrics from prometheus endpoint, %w", scan.Err())
+	}
+
+	sort.Sort(metrics)
+
+	// remove duplicates
+	for i := 0; i < len(*metrics)-1; i++ {
+		if (*metrics)[i].name == (*metrics)[i+1].name {
+			*metrics = append((*metrics)[:i], (*metrics)[i+1:]...)
+			i--
+		}
+	}
+
+	return nil
+}
+
+func checkError(err error) {
+	if err != nil {
+		panic(err)
+	}
+}