test: update tests for custom rule_group interval

This updates tests include `interval`'s and also includes a test to make
sure the rules render correctly when interval is not included.

Author: wbollock

internal/prometheus/storage_test.go

@@ -33,7 +33,7 @@ func TestIOWriterGroupedRulesYAMLRepoStore(t *testing.T) {
 		"Having a single SLI recording rule should render correctly.": {
 			slos: []prometheus.StorageSLO{
 				{
-					SLO: prometheus.SLO{ID: "test1"},
+					SLO: prometheus.SLO{ID: "test1", RuleGroupInterval: "2m"},
 					Rules: prometheus.SLORules{
 						SLIErrorRecRules: []rulefmt.Rule{
 							{
@@ -52,6 +52,7 @@ func TestIOWriterGroupedRulesYAMLRepoStore(t *testing.T) {
 
 groups:
 - name: sloth-slo-sli-recordings-test1
+  interval: 2m
   rules:
   - record: test:record
     expr: test-expr
@@ -91,7 +92,7 @@ groups:
 		"Having a single SLO alert rule should render correctly.": {
 			slos: []prometheus.StorageSLO{
 				{
-					SLO: prometheus.SLO{ID: "test1"},
+					SLO: prometheus.SLO{ID: "test1", RuleGroupInterval: "2m"},
 					Rules: prometheus.SLORules{
 						AlertRules: []rulefmt.Rule{
 							{
@@ -111,6 +112,7 @@ groups:
 
 groups:
 - name: sloth-slo-alerts-test1
+  interval: 2m
   rules:
   - alert: testAlert
     expr: test-expr
@@ -120,11 +122,40 @@ groups:
       test-annot: one
 `,
 		},
+		"Having a single a blank or empty rule_group interval render correctly.": {
+			slos: []prometheus.StorageSLO{
+				{
+					SLO: prometheus.SLO{ID: "test1", RuleGroupInterval: ""},
+					Rules: prometheus.SLORules{
+						SLIErrorRecRules: []rulefmt.Rule{
+							{
+								Record: "test:record",
+								Expr:   "test-expr",
+								Labels: map[string]string{"test-label": "one"},
+							},
+						},
+					},
+				},
+			},
+			expYAML: `
+---
+# Code generated by Sloth (dev): https://github.com/slok/sloth.
+# DO NOT EDIT.
+
+groups:
+- name: sloth-slo-sli-recordings-test1
+  rules:
+  - record: test:record
+    expr: test-expr
+    labels:
+      test-label: one
+`,
+		},
 
 		"Having a multiple SLO alert and recording rules should render correctly.": {
 			slos: []prometheus.StorageSLO{
 				{
-					SLO: prometheus.SLO{ID: "testa"},
+					SLO: prometheus.SLO{ID: "testa", RuleGroupInterval: "3m"},
 					Rules: prometheus.SLORules{
 						SLIErrorRecRules: []rulefmt.Rule{
 							{
@@ -167,7 +198,7 @@ groups:
 					},
 				},
 				{
-					SLO: prometheus.SLO{ID: "testb"},
+					SLO: prometheus.SLO{ID: "testb", RuleGroupInterval: "1h"},
 					Rules: prometheus.SLORules{
 						SLIErrorRecRules: []rulefmt.Rule{
 							{
@@ -201,6 +232,7 @@ groups:
 
 groups:
 - name: sloth-slo-sli-recordings-testa
+  interval: 3m
   rules:
   - record: test:record-a1
     expr: test-expr-a1
@@ -211,6 +243,7 @@ groups:
     labels:
       test-label: a-2
 - name: sloth-slo-meta-recordings-testa
+  interval: 3m
   rules:
   - record: test:record-a3
     expr: test-expr-a3
@@ -221,6 +254,7 @@ groups:
     labels:
       test-label: a-4
 - name: sloth-slo-alerts-testa
+  interval: 3m
   rules:
   - alert: testAlertA1
     expr: test-expr-a1
@@ -235,18 +269,21 @@ groups:
     annotations:
       test-annot: a-2
 - name: sloth-slo-sli-recordings-testb
+  interval: 1h
   rules:
   - record: test:record-b1
     expr: test-expr-b1
     labels:
       test-label: b-1
 - name: sloth-slo-meta-recordings-testb
+  interval: 1h
   rules:
   - record: test:record-b2
     expr: test-expr-b2
     labels:
       test-label: b-2
 - name: sloth-slo-alerts-testb
+  interval: 1h
   rules:
   - alert: testAlertB1
     expr: test-expr-b1