Add metrics to get issues by label (#17201)

* Add metrics to get issues by label

* Add comment on IssueByLabelCount

* Code review - Unify "AS" in SQL (#17201)

* Code review - Remove useless join (#17201)

* Code review - Disable issue_by_label by default in settings (#17201)

* use e

* restore empty line

* update docs

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: techknowlogick <matti@mdranta.net>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

custom/conf/app.example.ini

@@ -2041,6 +2041,8 @@ PATH =
 ;ENABLED = false
 ;; If you want to add authorization, specify a token here
 ;TOKEN =
+;; Enable issue by label metrics; default is false
+;ENABLED_ISSUE_BY_LABEL = false
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -853,6 +853,7 @@ NB: You must have `DISABLE_ROUTER_LOG` set to `false` for this option to take ef
 ## Metrics (`metrics`)
 
 - `ENABLED`: **false**: Enables /metrics endpoint for prometheus.
+- `ENABLED_ISSUE_BY_LABEL`: **false**: Enable issue by label metrics
 - `TOKEN`: **\<empty\>**: You need to specify the token, if you want to include in the authorization the metrics . The same token need to be used in prometheus parameters `bearer_token` or `bearer_token_file`.
 
 ## API (`api`)

models/statistic.go

@@ -7,6 +7,7 @@ package models
 import (
  "code.gitea.io/gitea/models/db"
  "code.gitea.io/gitea/models/login"
+ "code.gitea.io/gitea/modules/setting"
 )
 
 // Statistic contains the database statistics
@@ -20,9 +21,16 @@ type Statistic struct {
  Milestone, Label, HookTask,
  Team, UpdateTask, Project,
  ProjectBoard, Attachment int64
+ IssueByLabel []IssueByLabelCount
  }
 }
 
+// IssueByLabelCount contains the number of issue group by label
+type IssueByLabelCount struct {
+ Count int64
+ Label string
+}
+
 // GetStatistic returns the database statistics
 func GetStatistic() (stats Statistic) {
  e := db.GetEngine(db.DefaultContext)
@@ -39,6 +47,17 @@ func GetStatistic() (stats Statistic) {
  Count int64
  IsClosed bool
  }
+
+ if setting.Metrics.EnabledIssueByLabel {
+ stats.Counter.IssueByLabel = []IssueByLabelCount{}
+
+ _ = e.Select("COUNT(*) AS count, l.name AS label").
+ Join("LEFT", "label l", "l.id=il.label_id").
+ Table("issue_label il").
+ GroupBy("l.name").
+ Find(&stats.Counter.IssueByLabel)
+ }
+
  issueCounts := []IssueCount{}
 
  _ = e.Select("COUNT(*) AS count, is_closed").Table("issue").GroupBy("is_closed").Find(&issueCounts)

modules/metrics/collector.go

@@ -24,6 +24,7 @@ type Collector struct {
  Issues *prometheus.Desc
  IssuesOpen *prometheus.Desc
  IssuesClosed *prometheus.Desc
+ IssuesByLabel *prometheus.Desc
  Labels *prometheus.Desc
  LoginSources *prometheus.Desc
  Milestones *prometheus.Desc
@@ -45,6 +46,7 @@ type Collector struct {
 
 // NewCollector returns a new Collector with all prometheus.Desc initialized
 func NewCollector() Collector {
+
  return Collector{
  Accesses: prometheus.NewDesc(
  namespace+"accesses",
@@ -81,6 +83,11 @@ func NewCollector() Collector {
  "Number of Issues",
  nil, nil,
  ),
+ IssuesByLabel: prometheus.NewDesc(
+ namespace+"issues_by_label",
+ "Number of Issues",
+ []string{"label"}, nil,
+ ),
  IssuesOpen: prometheus.NewDesc(
  namespace+"issues_open",
  "Number of open Issues",
@@ -177,7 +184,6 @@ func NewCollector() Collector {
  nil, nil,
  ),
  }
-
 }
 
 // Describe returns all possible prometheus.Desc
@@ -189,6 +195,7 @@ func (c Collector) Describe(ch chan<- *prometheus.Desc) {
  ch <- c.Follows
  ch <- c.HookTasks
  ch <- c.Issues
+ ch <- c.IssuesByLabel
  ch <- c.IssuesOpen
  ch <- c.IssuesClosed
  ch <- c.Labels
@@ -249,6 +256,14 @@ func (c Collector) Collect(ch chan<- prometheus.Metric) {
  prometheus.GaugeValue,
  float64(stats.Counter.Issue),
  )
+ for _, il := range stats.Counter.IssueByLabel {
+ ch <- prometheus.MustNewConstMetric(
+ c.IssuesByLabel,
+ prometheus.GaugeValue,
+ float64(il.Count),
+ il.Label,
+ )
+ }
  ch <- prometheus.MustNewConstMetric(
  c.IssuesClosed,
  prometheus.GaugeValue,

modules/setting/setting.go

@@ -390,11 +390,13 @@ var (
 
  // Metrics settings
  Metrics = struct {
- Enabled bool
- Token string
+ Enabled bool
+ Token string
+ EnabledIssueByLabel bool
  }{
- Enabled: false,
- Token: "",
+ Enabled: false,
+ Token: "",
+ EnabledIssueByLabel: false,
  }
 
  // I18n settings