Add Elasticache resources for Discourse to Mesos cluster

discourse.tf

@@ -0,0 +1,19 @@
+module "discourse-production" {
+    source                              = "./modules/discourse"
+
+    environment                         = "production"
+    vpc_id                              = "${aws_vpc.apps-production-vpc.id}"
+    discourse_elasticache_instance_size = "cache.t2.medium"
+    service_security_group_id           = "${module.mesos-cluster-production.mesos-cluster-slave-sg-id}"
+    elasticache_subnet_group            = "${aws_elasticache_subnet_group.elasticache-production-subnet-group.name}"
+}
+
+module "discourse-staging" {
+    source                              = "./modules/discourse"
+
+    environment                         = "staging"
+    vpc_id                              = "${aws_vpc.apps-staging-vpc.id}"
+    discourse_elasticache_instance_size = "cache.t2.micro"
+    service_security_group_id           = "${module.mesos-cluster-staging.mesos-cluster-slave-sg-id}"
+    elasticache_subnet_group            = "${aws_elasticache_subnet_group.elasticache-staging-subnet-group.name}"
+}

mesos-cluster.tf

@@ -14,6 +14,7 @@ module "mesos-cluster-staging" {
     subnet2              = "${aws_subnet.apps-staging-1c.id}"
     subnet3              = "${aws_subnet.apps-staging-1d.id}"
 }
+
 module "mesos-cluster-production" {
     source               = "./modules/mesos-cluster"
     # provider vars

modules/discourse/main.tf

@@ -0,0 +1,47 @@
+variable "vpc_id" {}
+variable "discourse_elasticache_instance_size" {}
+variable "elasticache_subnet_group" {}
+variable "service_security_group_id" {}
+variable "environment" {}
+
+resource "aws_security_group" "discourse-redis-sg" {
+    name                     = "discourse-redis-shared-sg"
+    description              = "discourse elasticache SG"
+    vpc_id                   = "${var.vpc_id}"
+}
+
+resource "aws_security_group_rule" "discourse-redis-sg-allowredisfromslaves" {
+    type                     = "ingress"
+    from_port                = 6379
+    to_port                  = 6379
+    protocol                 = "tcp"
+    source_security_group_id = "${var.service_security_group_id}"
+    security_group_id        = "${aws_security_group.discourse-redis-sg.id}"
+}
+
+resource "aws_security_group_rule" "discourse-redis-sg-allowegress" {
+    type                     = "egress"
+    from_port                = 0
+    to_port                  = 0
+    protocol                 = "-1"
+    source_security_group_id = "${var.service_security_group_id}"
+    security_group_id        = "${aws_security_group.discourse-redis-sg.id}"
+}
+
+resource "aws_elasticache_cluster" "discourse-redis-ec" {
+    cluster_id                 = "discourse-${var.environment}"
+    engine                     = "redis"
+    engine_version             = "2.8.24"
+    node_type                  = "${var.discourse_elasticache_instance_size}"
+    port                       = 6379
+    num_cache_nodes            = 1
+    parameter_group_name       = "default.redis2.8"
+    subnet_group_name          = "${var.elasticache_subnet_group}"
+    security_group_ids         = ["${aws_security_group.discourse-redis-sg.id}"]
+    tags {
+        Name                   = "discourse-${var.environment}-redis"
+        app                    = "redis"
+        env                    = "${var.environment}"
+        project                = "discourse"
+    }
+}

monitoring.tf

@@ -1,9 +1,3 @@
-resource "aws_elasticache_subnet_group" "elasticache-shared-subnet-group" {
-  name                 = "elasticache-shared-subnet-group"
-  subnet_ids           = ["${aws_subnet.apps-shared-1a.id}", "${aws_subnet.apps-shared-1c.id}", "${aws_subnet.apps-shared-1d.id}"]
-  description          = "Subnet group for shared VPC"
-}
-
 resource "aws_security_group" "sensu-redis-sg" {
   name                 = "sensu-redis-shared-sg"
   description          = "Sensu elasticache SG"

network.tf

@@ -371,3 +371,23 @@ resource "aws_route_table_association" "apps-shared-1d-rtbassoc" {
     route_table_id = "${aws_route_table.apps-shared-rt.id}"
     subnet_id      = "${aws_subnet.apps-shared-1d.id}"
 }
+
+# Elasticache subnet groups
+
+resource "aws_elasticache_subnet_group" "elasticache-shared-subnet-group" {
+  name                 = "elasticache-shared-subnet-group"
+  subnet_ids           = ["${aws_subnet.apps-shared-1a.id}", "${aws_subnet.apps-shared-1c.id}", "${aws_subnet.apps-shared-1d.id}"]
+  description          = "Subnet group for shared VPC"
+}
+
+resource "aws_elasticache_subnet_group" "elasticache-staging-subnet-group" {
+  name                 = "elasticache-staging-subnet-group"
+  subnet_ids           = ["${aws_subnet.apps-staging-1a.id}", "${aws_subnet.apps-staging-1c.id}", "${aws_subnet.apps-staging-1d.id}"]
+  description          = "Subnet group for staging VPC"
+}
+
+resource "aws_elasticache_subnet_group" "elasticache-production-subnet-group" {
+  name                 = "elasticache-production-subnet-group"
+  subnet_ids           = ["${aws_subnet.apps-production-1a.id}", "${aws_subnet.apps-production-1c.id}", "${aws_subnet.apps-production-1d.id}"]
+  description          = "Subnet group for production VPC"
+}