Loki: Add lokiQueryHints feature flag (#78953)

* add `lokiQueryHints` feature flag

* language provider tests

* fix unwrap tests

* add feature toggle

pkg/services/featuremgmt/registry.go

@@ -1270,5 +1270,16 @@ var (
 			RequiresRestart:   true,
 			Created:           time.Date(2023, time.November, 30, 12, 0, 0, 0, time.UTC),
 		},
+		{
+			// this is mainly used a a way to quickly disable query hints as a safe guard for our infrastructure
+			Name:           "lokiQueryHints",
+			Description:    "Enables query hints for Loki",
+			Stage:          FeatureStageGeneralAvailability,
+			FrontendOnly:   true,
+			Expression:     "true",
+			Owner:          grafanaObservabilityLogsSquad,
+			AllowSelfServe: false,
+			Created:        time.Date(2023, time.December, 18, 12, 0, 0, 0, time.UTC),
+		},
 	}
 )

pkg/services/featuremgmt/toggles_gen.csv

@@ -150,3 +150,4 @@ tableSharedCrosshair,experimental,@grafana/grafana-bi-squad,2023-12-12,false,fal
 regressionTransformation,privatePreview,@grafana/grafana-bi-squad,2023-11-24,false,false,false,true
 displayAnonymousStats,GA,@grafana/identity-access-team,2023-11-29,false,false,false,true
 alertStateHistoryAnnotationsFromLoki,experimental,@grafana/alerting-squad,2023-11-30,false,false,true,false
+lokiQueryHints,GA,@grafana/observability-logs,2023-12-18,false,false,false,true

pkg/services/featuremgmt/toggles_gen.go

@@ -610,4 +610,8 @@ const (
 	// FlagAlertStateHistoryAnnotationsFromLoki
 	// Enable using Loki as the source for panel annotations generated by alert rules
 	FlagAlertStateHistoryAnnotationsFromLoki = "alertStateHistoryAnnotationsFromLoki"
+
+	// FlagLokiQueryHints
+	// Enables query hints for Loki
+	FlagLokiQueryHints = "lokiQueryHints"
 )