From 307b12d7824d70e03d3f23ae18f02d5d190a04c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wilson=20J=C3=BAnior?= <wilsonpjunior@gmail.com>
Date: Thu, 26 Dec 2019 17:05:54 -0300
Subject: [PATCH] Fix generation of rules for SLOs without latency

---
 slo/slo.go      | 2 +-
 slo/slo_test.go | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/slo/slo.go b/slo/slo.go
index 80d6694..d1a12c9 100644
--- a/slo/slo.go
+++ b/slo/slo.go
@@ -95,7 +95,7 @@ func (slo *SLO) GenerateAlertRules(sloClass *Class) []rulefmt.Rule {
 	}
 
 	latencyMethod := methods.Get(slo.LatencyRecord.AlertMethod)
-	if latencyMethod != nil {
+	if latencyMethod != nil && objectives.Latency != nil {
 		latencyRules := latencyMethod.AlertForLatency(slo.Name, objectives.Latency)
 		alertRules = append(alertRules, latencyRules...)
 	}
diff --git a/slo/slo_test.go b/slo/slo_test.go
index 9419763..d48a8f5 100644
--- a/slo/slo_test.go
+++ b/slo/slo_test.go
@@ -902,6 +902,12 @@ func TestSLOGenerateAlertRulesWithSLOCLass(t *testing.T) {
 			},
 		},
 	}
+	noLatencyClass := &Class{
+		Name: "LOW",
+		Objectives: Objectives{
+			Availability: 99,
+		},
+	}
 	slo := &SLO{
 		Name:  "my-team.my-service.payment",
 		Class: "HIGH",
@@ -997,4 +1003,7 @@ func TestSLOGenerateAlertRulesWithSLOCLass(t *testing.T) {
 		},
 		Annotations: slo.Annotations,
 	})
+
+	alertRules = slo.GenerateAlertRules(noLatencyClass)
+	assert.Len(t, alertRules, 2)
 }