MM-57214: Integrate Redis into Terraform deployment (#708)

https://mattermost.atlassian.net/browse/MM-57214

config/deployer.sample.json

@@ -20,6 +20,12 @@
     "RestoreTimeoutMinutes": 45,
     "ClusterTimeoutMinutes": 45
   },
+  "RedisSettings": {
+    "Enabled": false,
+    "NodeType": "cache.m7g.2xlarge",
+    "ParameterGroupName": "default.redis7",
+    "EngineVersion": "7.1"
+  },
   "JobServerSettings":{
     "InstanceCount": 0,
     "InstanceType": "c7i.xlarge"

deployment/config.go

@@ -75,6 +75,7 @@ type Config struct {
 	// the deployment process.
 	LoadTestDownloadURL   string `default:"https://github.com/mattermost/mattermost-load-test-ng/releases/download/v1.19.0/mattermost-load-test-ng-v1.19.0-linux-amd64.tar.gz" validate:"url"`
 	ElasticSearchSettings ElasticSearchSettings
+	RedisSettings         RedisSettings
 	JobServerSettings     JobServerSettings
 	LogSettings           logger.Settings
 	Report                report.Config
@@ -249,6 +250,17 @@ type ElasticSearchSettings struct {
 	ClusterTimeoutMinutes int `default:"45" validate:"range:[0,)"`
 }
 
+type RedisSettings struct {
+	// Enabled indicates whether to add Redis or not.
+	Enabled bool
+	// NodeType indicates the instance type.
+	NodeType string `default:"cache.m7g.2xlarge"`
+	// ParameterGroupName indicates the parameter group to attach.
+	ParameterGroupName string `default:"default.redis7"`
+	// EngineVersion indicates the engine version.
+	EngineVersion string `default:"7.1"`
+}
+
 // JobServerSettings contains the necessary data to deploy a job
 // server.
 type JobServerSettings struct {

deployment/terraform/assets/cluster.tf

@@ -129,7 +129,10 @@ resource "aws_instance" "metrics_server" {
       "sudo dpkg -i inbucket_2.1.0_linux_amd64.deb",
       "wget https://github.com/justwatchcom/elasticsearch_exporter/releases/download/v1.1.0/elasticsearch_exporter-1.1.0.linux-amd64.tar.gz",
       "sudo mkdir /opt/elasticsearch_exporter",
-      "sudo tar -zxvf elasticsearch_exporter-1.1.0.linux-amd64.tar.gz -C /opt/elasticsearch_exporter --strip-components=1",
+      "sudo tar -zxf elasticsearch_exporter-1.1.0.linux-amd64.tar.gz -C /opt/elasticsearch_exporter --strip-components=1",
+      "wget https://github.com/oliver006/redis_exporter/releases/download/v1.58.0/redis_exporter-v1.58.0.linux-amd64.tar.gz",
+      "sudo mkdir /opt/redis_exporter",
+      "sudo tar -zxf redis_exporter-v1.58.0.linux-amd64.tar.gz -C /opt/redis_exporter --strip-components=1",
       "sudo systemctl daemon-reload",
       "sudo systemctl enable grafana-server",
       "sudo service grafana-server start",
@@ -248,6 +251,19 @@ resource "aws_iam_user_policy" "s3userpolicy" {
 EOF
 }
 
+resource "aws_elasticache_cluster" "redis_server" {
+  cluster_id           = "${var.cluster_name}-redis"
+  engine               = "redis"
+  node_type            = "${var.redis_node_type}"
+  count                = var.redis_enabled ? 1 : 0
+  num_cache_nodes      = 1
+  parameter_group_name = "${var.redis_param_group_name}"
+  engine_version       = "${var.redis_engine_version}"
+  port                 = 6379
+
+  security_group_ids = [aws_security_group.redis[0].id]
+}
+
 resource "aws_rds_cluster" "db_cluster" {
   count               = var.app_instance_count > 0 && var.db_instance_count > 0 && var.db_cluster_identifier == "" ? 1 : 0
   cluster_identifier  = var.db_cluster_identifier != "" ? "" : "${var.cluster_name}-db"
@@ -536,6 +552,20 @@ resource "aws_security_group_rule" "metrics-egress" {
   security_group_id = aws_security_group.metrics[0].id
 }
 
+resource "aws_security_group" "redis" {
+  name        = "${var.cluster_name}-redis-security-group"
+  description = "Security group for redis instance"
+
+  ingress {
+    from_port       = 6379
+    to_port         = 6379
+    protocol        = "tcp"
+    security_groups = [aws_security_group.app[0].id, aws_security_group.metrics[0].id]
+  }
+
+  count = 1
+}
+
 resource "aws_security_group" "elastic" {
   name        = "${var.cluster_name}-elastic-security-group"
   description = "Security group for elastic instance"

deployment/terraform/assets/outputs.tf

@@ -31,6 +31,10 @@ output "elasticRoleARN" {
   value = aws_iam_role.es_role.arn
 }
 
+output "redisServer" {
+  value = aws_elasticache_cluster.redis_server
+}
+
 output "s3bucket" {
   value = aws_s3_bucket.s3bucket
 }