Instrumentation: Adds environment_info metric (#28355)

Signed-off-by: bergquist <carl.bergquist@gmail.com>

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/infra/metrics/metrics.go

@@ -513,6 +513,26 @@ func SetBuildInformation(version, revision, branch string) {
 	grafanaBuildVersion.WithLabelValues(version, revision, branch, runtime.Version(), edition).Set(1)
 }
 
+// SetEnvironmentInformation exposes environment values provided by the operators as an `_info` metric.
+// If there are no environment metrics labels configured, this metric will not be exposed.
+func SetEnvironmentInformation(labels map[string]string) error {
+	if len(labels) == 0 {
+		return nil
+	}
+
+	grafanaEnvironmentInfo := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name:        "environment_info",
+		Help:        "A metric with a constant '1' value labeled by environment information about the running instance.",
+		Namespace:   ExporterName,
+		ConstLabels: labels,
+	})
+
+	prometheus.MustRegister(grafanaEnvironmentInfo)
+
+	grafanaEnvironmentInfo.Set(1)
+	return nil
+}
+
 func SetPluginBuildInformation(pluginID, pluginType, version string) {
 	grafanaPluginBuildInfoDesc.WithLabelValues(pluginID, pluginType, version).Set(1)
 }

pkg/server/server.go

@@ -22,6 +22,7 @@ import (
 	_ "github.com/grafana/grafana/pkg/extensions"
 	"github.com/grafana/grafana/pkg/infra/localcache"
 	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/infra/metrics"
 	_ "github.com/grafana/grafana/pkg/infra/metrics"
 	_ "github.com/grafana/grafana/pkg/infra/remotecache"
 	_ "github.com/grafana/grafana/pkg/infra/serverlock"
@@ -117,6 +118,9 @@ func (s *Server) init(cfg *Config) error {
 
 	s.loadConfiguration()
 	s.writePIDFile()
+	if err := metrics.SetEnvironmentInformation(s.cfg.MetricsGrafanaEnvironmentInfo); err != nil {
+		return err
+	}
 
 	login.Init()
 	social.NewOAuthService()

pkg/setting/setting.go

@@ -17,6 +17,7 @@ import (
 	"time"
 
 	"github.com/go-macaron/session"
+	"github.com/prometheus/common/model"
 	ini "gopkg.in/ini.v1"
 
 	"github.com/grafana/grafana/pkg/components/gtime"
@@ -267,17 +268,20 @@ type Cfg struct {
 	CookieSameSiteDisabled           bool
 	CookieSameSiteMode               http.SameSite
 
-	TempDataLifetime                 time.Duration
+	TempDataLifetime         time.Duration
+	PluginsEnableAlpha       bool
+	PluginsAppsSkipVerifyTLS bool
+	PluginSettings           PluginSettings
+	PluginsAllowUnsigned     []string
+	DisableSanitizeHtml      bool
+	EnterpriseLicensePath    string
+
+	// Metrics
 	MetricsEndpointEnabled           bool
 	MetricsEndpointBasicAuthUsername string
 	MetricsEndpointBasicAuthPassword string
 	MetricsEndpointDisableTotalStats bool
-	PluginsEnableAlpha               bool
-	PluginsAppsSkipVerifyTLS         bool
-	PluginSettings                   PluginSettings
-	PluginsAllowUnsigned             []string
-	DisableSanitizeHtml              bool
-	EnterpriseLicensePath            string
+	MetricsGrafanaEnvironmentInfo    map[string]string
 
 	// Dashboards
 	DefaultHomeDashboardPath string
@@ -411,6 +415,29 @@ func applyEnvVariableOverrides(file *ini.File) error {
 	return nil
 }
 
+func (cfg *Cfg) readGrafanaEnvironmentMetrics() error {
+	environmentMetricsSection := cfg.Raw.Section("metrics.environment_info")
+	keys := environmentMetricsSection.Keys()
+	cfg.MetricsGrafanaEnvironmentInfo = make(map[string]string, len(keys))
+
+	for _, key := range keys {
+		labelName := model.LabelName(key.Name())
+		labelValue := model.LabelValue(key.Value())
+
+		if !labelName.IsValid() {
+			return fmt.Errorf("invalid label name in [metrics.environment_info] configuration. name %q", labelName)
+		}
+
+		if !labelValue.IsValid() {
+			return fmt.Errorf("invalid label value in [metrics.environment_info] configuration. name %q value %q", labelName, labelValue)
+		}
+
+		cfg.MetricsGrafanaEnvironmentInfo[string(labelName)] = string(labelValue)
+	}
+
+	return nil
+}
+
 func (cfg *Cfg) readAnnotationSettings() {
 	dashboardAnnotation := cfg.Raw.Section("annotations.dashboard")
 	apiIAnnotation := cfg.Raw.Section("annotations.api")
@@ -781,6 +808,9 @@ func (cfg *Cfg) Load(args *CommandLineArgs) error {
 	cfg.readSmtpSettings()
 	cfg.readQuotaSettings()
 	cfg.readAnnotationSettings()
+	if err := cfg.readGrafanaEnvironmentMetrics(); err != nil {
+		return err
+	}
 
 	if VerifyEmailEnabled && !cfg.Smtp.Enabled {
 		log.Warnf("require_email_validation is enabled but smtp is disabled")