Alerting: Handle NoData and Error evaluation results (#33194)

* set processing time

* merge labels and set on response

* use state cache for adding alerts to rules

* minor cleanup

* add support for NoData and Error results

* rename test

* bring in changes from other PRs tha have been merged

* pr feedback

* add integration test

* close state tracker cleanup on context.Done

* fixup test

* not those annotations

pkg/services/ngalert/api/api_prometheus.go

@@ -51,7 +51,9 @@ func (srv PrometheusSrv) RouteGetRuleStatuses(c *models.ReqContext) response.Res
 		DiscoveryBase: apimodels.DiscoveryBase{
 			Status: "success",
 		},
-		Data: apimodels.RuleDiscovery{},
+		Data: apimodels.RuleDiscovery{
+			RuleGroups: []*apimodels.RuleGroup{},
+		},
 	}
 
 	ruleGroupQuery := ngmodels.ListOrgRuleGroupsQuery{
@@ -99,7 +101,7 @@ func (srv PrometheusSrv) RouteGetRuleStatuses(c *models.ReqContext) response.Res
 			newRule := apimodels.Rule{
 				Name:           rule.Title,
 				Labels:         rule.Labels,
-				Health:         "ok", // TODO: update this in the future when error and noData states are being evaluated and set
+				Health:         "ok",
 				Type:           apiv1.RuleTypeAlerting,
 				LastEvaluation: time.Time{},
 			}
@@ -131,9 +133,9 @@ func (srv PrometheusSrv) RouteGetRuleStatuses(c *models.ReqContext) response.Res
 				case eval.Alerting:
 					alertingRule.State = "firing"
 				case eval.Error:
-					// handle Error case based on configuration in alertRule
+					newRule.Health = "error"
 				case eval.NoData:
-					// handle NoData case based on configuration in alertRule
+					newRule.Health = "nodata"
 				}
 				alertingRule.Alerts = append(alertingRule.Alerts, alert)
 			}