Alerting: refactor rule API to create rule group in a single place (#48915)

* extract method toGettableRuleGroupConfig

pkg/services/ngalert/api/api_ruler.go

@@ -226,9 +226,6 @@ func (srv RulerSrv) RouteGetRulesGroupConfig(c *models.ReqContext) response.Resp
 		return ErrResp(http.StatusInternalServerError, err, "failed to get group alert rules")
 	}
 
-	var ruleGroupInterval model.Duration
-	ruleNodes := make([]apimodels.GettableExtendedRuleNode, 0, len(q.Result))
-
 	hasAccess := func(evaluator accesscontrol.Evaluator) bool {
 		return accesscontrol.HasAccess(srv.ac, c)(accesscontrol.ReqSignedIn, evaluator)
 	}
@@ -238,20 +235,16 @@ func (srv RulerSrv) RouteGetRulesGroupConfig(c *models.ReqContext) response.Resp
 		return ErrResp(http.StatusInternalServerError, err, "failed to get group alert rules")
 	}
 
+	groupRules := make([]*ngmodels.AlertRule, 0, len(q.Result))
 	for _, r := range q.Result {
 		if !authorizeDatasourceAccessForRule(r, hasAccess) {
 			continue
 		}
-		ruleGroupInterval = model.Duration(time.Duration(r.IntervalSeconds) * time.Second)
-		ruleNodes = append(ruleNodes, toGettableExtendedRuleNode(*r, namespace.Id, provenanceRecords))
+		groupRules = append(groupRules, r)
 	}
 
 	result := apimodels.RuleGroupConfigResponse{
-		GettableRuleGroupConfig: apimodels.GettableRuleGroupConfig{
-			Name:     ruleGroup,
-			Interval: ruleGroupInterval,
-			Rules:    ruleNodes,
-		},
+		GettableRuleGroupConfig: toGettableRuleGroupConfig(ruleGroup, groupRules, namespace.Id, provenanceRecords),
 	}
 	return response.JSON(http.StatusAccepted, result)
 }
@@ -293,7 +286,7 @@ func (srv RulerSrv) RouteGetRulesConfig(c *models.ReqContext) response.Response
 		return ErrResp(http.StatusInternalServerError, err, "failed to get alert rules")
 	}
 
-	configs := make(map[string]map[string]apimodels.GettableRuleGroupConfig)
+	configs := make(map[string]map[string][]*ngmodels.AlertRule)
 
 	hasAccess := func(evaluator accesscontrol.Evaluator) bool {
 		return accesscontrol.HasAccess(srv.ac, c)(accesscontrol.ReqSignedIn, evaluator)
@@ -308,44 +301,25 @@ func (srv RulerSrv) RouteGetRulesConfig(c *models.ReqContext) response.Response
 		if !authorizeDatasourceAccessForRule(r, hasAccess) {
 			continue
 		}
-		folder, ok := namespaceMap[r.NamespaceUID]
+		namespaceCfgs, ok := configs[r.NamespaceUID]
 		if !ok {
-			srv.log.Error("namespace not visible to the user", "user", c.SignedInUser.UserId, "namespace", r.NamespaceUID, "rule", r.UID)
-			continue
-		}
-		namespace := folder.Title
-		_, ok = configs[namespace]
-		if !ok {
-			ruleGroupInterval := model.Duration(time.Duration(r.IntervalSeconds) * time.Second)
-			configs[namespace] = make(map[string]apimodels.GettableRuleGroupConfig)
-			configs[namespace][r.RuleGroup] = apimodels.GettableRuleGroupConfig{
-				Name:     r.RuleGroup,
-				Interval: ruleGroupInterval,
-				Rules: []apimodels.GettableExtendedRuleNode{
-					toGettableExtendedRuleNode(*r, folder.Id, provenanceRecords),
-				},
-			}
-		} else {
-			ruleGroupConfig, ok := configs[namespace][r.RuleGroup]
-			if !ok {
-				ruleGroupInterval := model.Duration(time.Duration(r.IntervalSeconds) * time.Second)
-				configs[namespace][r.RuleGroup] = apimodels.GettableRuleGroupConfig{
-					Name:     r.RuleGroup,
-					Interval: ruleGroupInterval,
-					Rules: []apimodels.GettableExtendedRuleNode{
-						toGettableExtendedRuleNode(*r, folder.Id, provenanceRecords),
-					},
-				}
-			} else {
-				ruleGroupConfig.Rules = append(ruleGroupConfig.Rules, toGettableExtendedRuleNode(*r, folder.Id, provenanceRecords))
-				configs[namespace][r.RuleGroup] = ruleGroupConfig
-			}
+			namespaceCfgs = make(map[string][]*ngmodels.AlertRule)
+			configs[r.NamespaceUID] = namespaceCfgs
 		}
+		group := namespaceCfgs[r.RuleGroup]
+		group = append(group, r)
+		namespaceCfgs[r.RuleGroup] = group
 	}
 
-	for namespace, m := range configs {
-		for _, ruleGroupConfig := range m {
-			result[namespace] = append(result[namespace], ruleGroupConfig)
+	for namespaceUID, m := range configs {
+		folder, ok := namespaceMap[namespaceUID]
+		if !ok {
+			srv.log.Error("namespace not visible to the user", "user", c.SignedInUser.UserId, "namespace", namespaceUID)
+			continue
+		}
+		namespace := folder.Title
+		for groupName, groupRules := range m {
+			result[namespace] = append(result[namespace], toGettableRuleGroupConfig(groupName, groupRules, folder.Id, provenanceRecords))
 		}
 	}
 	return response.JSON(http.StatusOK, result)
@@ -526,6 +500,22 @@ func (srv RulerSrv) updateAlertRulesInGroup(c *models.ReqContext, namespace *mod
 	return response.JSON(http.StatusAccepted, util.DynMap{"message": "rule group updated successfully"})
 }
 
+func toGettableRuleGroupConfig(groupName string, rules []*ngmodels.AlertRule, namespaceID int64, provenanceRecords map[string]ngmodels.Provenance) apimodels.GettableRuleGroupConfig {
+	ruleNodes := make([]apimodels.GettableExtendedRuleNode, 0, len(rules))
+	var interval time.Duration
+	if len(rules) > 0 {
+		interval = time.Duration(rules[0].IntervalSeconds) * time.Second
+	}
+	for _, r := range rules {
+		ruleNodes = append(ruleNodes, toGettableExtendedRuleNode(*r, namespaceID, provenanceRecords))
+	}
+	return apimodels.GettableRuleGroupConfig{
+		Name:     groupName,
+		Interval: model.Duration(interval),
+		Rules:    ruleNodes,
+	}
+}
+
 func toGettableExtendedRuleNode(r ngmodels.AlertRule, namespaceID int64, provenanceRecords map[string]ngmodels.Provenance) apimodels.GettableExtendedRuleNode {
 	provenance := ngmodels.ProvenanceNone
 	if prov, exists := provenanceRecords[r.ResourceID()]; exists {