feat: defaults when node_count is 1

aws-redis.yml

@@ -109,7 +109,7 @@ provision:
     prohibit_update: true
   - field_name: multi_az_enabled
     type: boolean
-    details: Whether to enable Multi-AZ Support for the replication group. If true, `node_count` must be greater than 1.
+    details: Whether to enable Multi-AZ Support for the replication group. Only applies when `node_count` is greater than 1.
     default: true
   - field_name: kms_key_id
     type: string
@@ -118,7 +118,7 @@ provision:
     prohibit_update: true
   - field_name: automatic_failover_enabled
     type: boolean
-    details: Automatically promote replica to primary if the existing primary fails. If enabled, node_count must be greater than 1.
+    details: Automatically promote replica to primary if the existing primary fails. Only applies when `node_count` is greater than 1.
     default: true
   - <<: &nullable_string
       type: string

terraform-tests/redis_test.go

@@ -7,7 +7,6 @@ import (
 	tfjson "github.com/hashicorp/terraform-json"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
-	"github.com/onsi/gomega/gbytes"
 	. "github.com/onsi/gomega/gstruct"
 )
 
@@ -244,20 +243,6 @@ var _ = Describe("Redis", Label("redis-terraform"), Ordered, func() {
 		})
 	})
 
-	Context("multi_az_enabled", func() {
-		When("invalid combination", func() {
-			It("should not be passed", func() {
-				vars := buildVars(defaultVars, map[string]any{"node_count": 1, "multi_az_enabled": true, "automatic_failover_enabled": false})
-				session, err := FailPlan(terraformProvisionDir, vars)
-
-				Expect(session.ExitCode()).NotTo(Equal(0), "Terraform plan should return and error upon exit")
-				Expect(session.Err).To(gbytes.Say("automatic_failover_enabled must be true if multi_az_enabled is true"))
-
-				Expect(err).NotTo(HaveOccurred())
-			})
-		})
-	})
-
 	Context("preferred_azs are passed", func() {
 		BeforeAll(func() {
 			plan = ShowPlan(terraformProvisionDir, buildVars(defaultVars, map[string]any{
@@ -400,6 +385,21 @@ var _ = Describe("Redis", Label("redis-terraform"), Ordered, func() {
 			})
 		})
 	})
+
+	Context("node_count is 1", func() {
+		BeforeAll(func() {
+			plan = ShowPlan(terraformProvisionDir, buildVars(defaultVars, map[string]any{
+				"node_count": 1,
+			}))
+		})
+
+		It("sets `automatic_failover_enabled` and `multi_az_enabled` to false", func() {
+			Expect(AfterValuesForType(plan, resource)).To(MatchKeys(IgnoreExtras, Keys{
+				"automatic_failover_enabled": BeFalse(),
+				"multi_az_enabled":           BeFalse(),
+			}))
+		})
+	})
 })
 
 func getExpectedResources() []string {

terraform/redis/cluster/provision/main.tf

@@ -44,8 +44,8 @@ resource "random_password" "auth_token" {
 }
 
 resource "aws_elasticache_replication_group" "redis" {
-  automatic_failover_enabled  = var.automatic_failover_enabled
-  multi_az_enabled            = var.multi_az_enabled
+  automatic_failover_enabled  = var.node_count == 1 ? false : var.automatic_failover_enabled
+  multi_az_enabled            = var.node_count == 1 ? false : var.multi_az_enabled
   replication_group_id        = var.instance_name
   description                 = format("%s redis", var.instance_name)
   node_type                   = local.node_type