Prometheus: Add flag to compare streaming and buffered responses (#51711)

* Add flag to compare streaming and buffered

* Move log

* Fix lint

* Fix tests

* Remove debug logs

pkg/services/featuremgmt/registry.go

@@ -191,6 +191,11 @@ var (
 			Description: "Enable streaming JSON parser for Prometheus datasource",
 			State:       FeatureStateBeta,
 		},
+		{
+			Name:        "prometheusStreamingJSONParserTest",
+			Description: "Run both old and streaming requests and log differences",
+			State:       FeatureStateBeta,
+		},
 		{
 			Name:            "validateDashboardsOnSave",
 			Description:     "Validate dashboard JSON POSTed to api/dashboards/db",

pkg/services/featuremgmt/toggles_gen.go

@@ -143,6 +143,10 @@ const (
 	// Enable streaming JSON parser for Prometheus datasource
 	FlagPrometheusStreamingJSONParser = "prometheusStreamingJSONParser"
 
+	// FlagPrometheusStreamingJSONParserTest
+	// Run both old and streaming requests and log differences
+	FlagPrometheusStreamingJSONParserTest = "prometheusStreamingJSONParserTest"
+
 	// FlagValidateDashboardsOnSave
 	// Validate dashboard JSON POSTed to api/dashboards/db
 	FlagValidateDashboardsOnSave = "validateDashboardsOnSave"