Add support for Limit field on RuleGroup which got introduced in prometheus/prometheus#9260 (#5528)

Signed-off-by: Krishna Teja Puttagunta <[email protected]>

Author: krishnateja325

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changelog
 
 ## master / unreleased
+* [FEATURE] Ruler: Add support for Limit field on RuleGroup. #5528
 * [FEATURE] AlertManager: Add support for Webex, Discord and Telegram Receiver. #5493
 * [FEATURE] Ingester: added `-admin-limit-message` to customize the message contained in limit errors.#5460
 * [CHANGE] AlertManager: include reason label in cortex_alertmanager_notifications_failed_total.#5409

pkg/ruler/api.go

@@ -69,6 +69,7 @@ type RuleGroup struct {
 	Interval       float64   `json:"interval"`
 	LastEvaluation time.Time `json:"lastEvaluation"`
 	EvaluationTime float64   `json:"evaluationTime"`
+	Limit          int64     `json:"limit"`
 }
 
 type rule interface{}
@@ -203,6 +204,7 @@ func (a *API) PrometheusRules(w http.ResponseWriter, req *http.Request) {
 			Interval:       g.Group.Interval.Seconds(),
 			LastEvaluation: g.GetEvaluationTimestamp(),
 			EvaluationTime: g.GetEvaluationDuration().Seconds(),
+			Limit:          g.Group.Limit,
 		}
 
 		for i, rl := range g.ActiveRules {

pkg/ruler/api_test.go

@@ -127,10 +127,63 @@ func TestRuler_rules_special_characters(t *testing.T) {
 			},
 		},
 	})
-
 	require.Equal(t, string(expectedResponse), string(body))
 }
 
+func TestRuler_rules_limit(t *testing.T) {
+	store := newMockRuleStore(mockRulesLimit)
+	cfg := defaultRulerConfig(t)
+
+	r := newTestRuler(t, cfg, store, nil)
+	defer services.StopAndAwaitTerminated(context.Background(), r) //nolint:errcheck
+
+	a := NewAPI(r, r.store, log.NewNopLogger())
+
+	req := requestFor(t, http.MethodGet, "https://localhost:8080/api/prom/api/v1/rules", nil, "user1")
+	w := httptest.NewRecorder()
+	a.PrometheusRules(w, req)
+
+	resp := w.Result()
+	body, _ := io.ReadAll(resp.Body)
+	// Check status code and status response
+	responseJSON := response{}
+	err := json.Unmarshal(body, &responseJSON)
+	require.NoError(t, err)
+	require.Equal(t, http.StatusOK, resp.StatusCode)
+	require.Equal(t, responseJSON.Status, "success")
+
+	// Testing the running rules for user1 in the mock store
+	expectedResponse, _ := json.Marshal(response{
+		Status: "success",
+		Data: &RuleDiscovery{
+			RuleGroups: []*RuleGroup{
+				{
+					Name:  "group1",
+					File:  "namespace1",
+					Limit: 5,
+					Rules: []rule{
+						&recordingRule{
+							Name:   "UP_RULE",
+							Query:  "up",
+							Health: "unknown",
+							Type:   "recording",
+						},
+						&alertingRule{
+							Name:   "UP_ALERT",
+							Query:  "up < 1",
+							State:  "inactive",
+							Health: "unknown",
+							Type:   "alerting",
+							Alerts: []*Alert{},
+						},
+					},
+					Interval: 60,
+				},
+			},
+		},
+	})
+	require.Equal(t, string(expectedResponse), string(body))
+}
 func TestRuler_alerts(t *testing.T) {
 	store := newMockRuleStore(mockRules)
 	cfg := defaultRulerConfig(t)

pkg/ruler/ruler.go

@@ -708,6 +708,7 @@ func (r *Ruler) getLocalRules(userID string, rulesRequest RulesRequest) ([]*Grou
 				Namespace: string(decodedNamespace),
 				Interval:  interval,
 				User:      userID,
+				Limit:     int64(group.Limit()),
 			},
 
 			EvaluationTimestamp: group.GetLastEvaluation(),

pkg/ruler/rulespb/compat.go

@@ -19,6 +19,7 @@ func ToProto(user string, namespace string, rl rulefmt.RuleGroup) *RuleGroupDesc
 		Interval:  time.Duration(rl.Interval),
 		Rules:     formattedRuleToProto(rl.Rules),
 		User:      user,
+		Limit:     int64(rl.Limit),
 	}
 	return &rg
 }
@@ -45,6 +46,7 @@ func FromProto(rg *RuleGroupDesc) rulefmt.RuleGroup {
 		Name:     rg.GetName(),
 		Interval: model.Duration(rg.Interval),
 		Rules:    make([]rulefmt.RuleNode, len(rg.GetRules())),
+		Limit:    int(rg.Limit),
 	}
 
 	for i, rl := range rg.GetRules() {

pkg/ruler/rulespb/rules.pb.go

@@ -27,6 +27,7 @@ message RuleGroupDesc {
   // to create custom `ManagerOpts` based on rule configs which can then be passed
   // to the Prometheus Manager.
   repeated google.protobuf.Any options = 9;
+  int64 limit =10;
 }
 
 // RuleDesc is a proto representation of a Prometheus Rule

pkg/ruler/rulespb/rules.proto

@@ -110,6 +110,27 @@ var (
 			},
 		},
 	}
+	mockRulesLimit = map[string]rulespb.RuleGroupList{
+		"user1": {
+			&rulespb.RuleGroupDesc{
+				Name:      "group1",
+				Namespace: "namespace1",
+				User:      "user1",
+				Limit:     5,
+				Rules: []*rulespb.RuleDesc{
+					{
+						Record: "UP_RULE",
+						Expr:   "up",
+					},
+					{
+						Alert: "UP_ALERT",
+						Expr:  "up < 1",
+					},
+				},
+				Interval: interval,
+			},
+		},
+	}
 )
 
 func newMockRuleStore(rules map[string]rulespb.RuleGroupList) *mockRuleStore {