Added ASG template, explicit types in module arguments

asg/files/instance-config.yml.tpl

@@ -0,0 +1,2 @@
+#instance-config
+${custom_script}

asg/main.tf

@@ -0,0 +1,292 @@
+/**
+ */
+
+variable "name" {
+  description = "The cluster name, e.g cdn"
+  type = "string"
+}
+
+variable "environment" {
+  description = "Environment tag, e.g prod"
+  type = "string"
+}
+
+variable "vpc_id" {
+  description = "VPC ID"
+  type = "string"
+}
+
+variable "image_id" {
+  description = "AMI Image ID"
+  type = "string"
+}
+
+variable "subnet_ids" {
+  description = "list of subnet IDs"
+  type = "list"
+}
+
+variable "key_name" {
+  description = "SSH key name to use"
+  type = "string"
+}
+
+variable "ingress_cidr" {
+  description = "Comma separated list of ingress cidrs"
+  type = "string"
+}
+
+variable "iam_instance_profile" {
+  description = "Instance profile ARN to use in the launch configuration"
+  type = "string"
+}
+
+variable "region" {
+  description = "AWS Region"
+  type = "string"
+}
+
+variable "availability_zones" {
+  description = "list of AZs"
+  type = "list"
+}
+
+variable "instance_type" {
+  description = "The instance type to use, e.g t2.small"
+  type = "string"
+}
+
+variable "instance_ebs_optimized" {
+  description = "When set to true the instance will be launched with EBS optimized turned on"
+  default     = true
+}
+
+variable "min_size" {
+  description = "Minimum instance count"
+  default     = 3
+}
+
+variable "max_size" {
+  description = "Maxmimum instance count"
+  default     = 100
+}
+
+variable "desired_capacity" {
+  description = "Desired instance count"
+  default     = 3
+}
+
+variable "associate_public_ip_address" {
+  description = "Should created instances be publicly accessible (if the SG allows)"
+  default     = false
+}
+
+variable "custom_script" {
+  description = "Custom instance bootupt script"
+  default     = ""
+  type = "string"
+}
+
+variable "load_balancers" {
+  description = "ASG ELBs"
+  default     = []
+}
+
+variable "health_check_grace_period" {
+  description = "Time (in seconds) after instance comes into service before checking health"
+  default     = 300
+}
+
+variable "target_group_arns" {
+  description = "Application load balancer target group ARN(s)  if any"
+  default     = []
+}
+
+variable "termination_policies" {
+  description = "OldestInstance, NewestInstance, OldestLaunchConfiguration, ClosestToNextInstanceHour, Default"
+  default     = ["OldestLaunchConfiguration", "Default"]
+}
+
+variable "wait_for_capacity_timeout" {
+  description = "A maximum duration that Terraform should wait for ASG instances to be healthy before timing out"
+  default     = "10m"
+}
+
+resource "aws_security_group" "asg" {
+  name        = "${var.name}-asg"
+  vpc_id      = "${var.vpc_id}"
+  description = "Allows traffic from and to the EC2 instances of the ${var.name} ASG"
+
+  ingress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = -1
+    cidr_blocks = ["${split(",", var.ingress_cidr)}"]
+  }
+
+  egress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = -1
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  tags {
+    Name        = "ASG (${var.name})"
+    Environment = "${var.environment}"
+  }
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+data "template_file" "instance_config" {
+  template = "${file("${path.module}/files/instance-config.yml.tpl")}"
+
+  vars {
+    custom_script = "${var.custom_script}"
+  }
+}
+
+resource "aws_launch_configuration" "main" {
+  name_prefix = "${format("%s-", var.name)}"
+
+  image_id                    = "${var.image_id}"
+  instance_type               = "${var.instance_type}"
+  ebs_optimized               = "${var.instance_ebs_optimized}"
+  iam_instance_profile        = "${var.iam_instance_profile}"
+  key_name                    = "${var.key_name}"
+  security_groups             = ["${aws_security_group.asg.id}"]
+  user_data                   = "${data.template_file.instance_config.rendered}"
+  associate_public_ip_address = "${var.associate_public_ip_address}"
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+resource "aws_autoscaling_group" "main" {
+  name = "${var.name}"
+
+  availability_zones        = ["${var.availability_zones}"]
+  vpc_zone_identifier       = ["${var.subnet_ids}"]
+  launch_configuration      = "${aws_launch_configuration.main.id}"
+  min_size                  = "${var.min_size}"
+  max_size                  = "${var.max_size}"
+  desired_capacity          = "${var.desired_capacity}"
+  health_check_grace_period = "${var.health_check_grace_period}"
+  health_check_type         = "ELB"
+  load_balancers            = ["${var.load_balancers}"]
+  target_group_arns         = ["${var.target_group_arns}"]
+  termination_policies      = "${var.termination_policies}"
+  wait_for_capacity_timeout = "${var.wait_for_capacity_timeout}"
+
+  tag {
+    key                 = "Name"
+    value               = "${var.name}"
+    propagate_at_launch = true
+  }
+
+  tag {
+    key                 = "Cluster"
+    value               = "${var.name}"
+    propagate_at_launch = true
+  }
+
+  tag {
+    key                 = "Environment"
+    value               = "${var.environment}"
+    propagate_at_launch = true
+  }
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+resource "aws_autoscaling_policy" "scale_up" {
+  name                   = "${var.name}-scaleup"
+  scaling_adjustment     = 1
+  adjustment_type        = "ChangeInCapacity"
+  cooldown               = 300
+  autoscaling_group_name = "${aws_autoscaling_group.main.name}"
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+resource "aws_autoscaling_policy" "scale_down" {
+  name                   = "${var.name}-scaledown"
+  scaling_adjustment     = -1
+  adjustment_type        = "ChangeInCapacity"
+  cooldown               = 300
+  autoscaling_group_name = "${aws_autoscaling_group.main.name}"
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+resource "aws_cloudwatch_metric_alarm" "cpu_high" {
+  alarm_name          = "${var.name}-cpureservation-high"
+  comparison_operator = "GreaterThanOrEqualToThreshold"
+  evaluation_periods  = "2"
+  metric_name         = "CPUUtilization"
+  namespace           = "AWS/EC2"
+  period              = "300"
+  statistic           = "Maximum"
+  threshold           = "60"
+
+  dimensions {
+    AutoScalingGroupName = "${aws_autoscaling_group.main.name}"
+  }
+
+  alarm_description = "Scale up if the cpu reservation is above 60% for 10 minutes"
+  alarm_actions     = ["${aws_autoscaling_policy.scale_up.arn}"]
+
+  lifecycle {
+    create_before_destroy = true
+  }
+
+  # This is required to make cloudwatch alarms creation sequential, AWS doesn't
+  # support modifying alarms concurrently.
+  depends_on = ["aws_autoscaling_group.main"]
+}
+
+resource "aws_cloudwatch_metric_alarm" "cpu_low" {
+  alarm_name          = "${var.name}-cpureservation-low"
+  comparison_operator = "LessThanOrEqualToThreshold"
+  evaluation_periods  = "2"
+  metric_name         = "CPUUtilization"
+  namespace           = "AWS/EC2"
+  period              = "300"
+  statistic           = "Maximum"
+  threshold           = "10"
+
+  dimensions {
+    AutoScalingGroupName = "${aws_autoscaling_group.main.name}"
+  }
+
+  alarm_description = "Scale down if the cpu reservation is below 10% for 10 minutes"
+  alarm_actions     = ["${aws_autoscaling_policy.scale_down.arn}"]
+
+  lifecycle {
+    create_before_destroy = true
+  }
+
+  # This is required to make cloudwatch alarms creation sequential, AWS doesn't
+  # support modifying alarms concurrently.
+  depends_on = ["aws_cloudwatch_metric_alarm.cpu_high"]
+}
+
+// The asg name, e.g cdn
+output "name" {
+  value = "${var.name}"
+}
+
+// The asg security group ID.
+output "security_group_id" {
+  value = "${aws_security_group.asg.id}"
+}

bastion/main.tf

@@ -24,14 +24,17 @@
 variable "instance_type" {
   default     = "t2.micro"
   description = "Instance type, see a list at: https://aws.amazon.com/ec2/instance-types/"
+  type = "string"
 }
 
 variable "region" {
   description = "AWS Region, e.g us-west-2"
+  type = "string"
 }
 
 variable "security_groups" {
-  description = "a comma separated lists of security group IDs"
+  description = "List of security group IDs"
+  type = "list"
 }
 
 variable "vpc_id" {
@@ -63,7 +66,7 @@ resource "aws_instance" "bastion" {
   instance_type          = "${var.instance_type}"
   subnet_id              = "${var.subnet_id}"
   key_name               = "${var.key_name}"
-  vpc_security_group_ids = ["${split(",",var.security_groups)}"]
+  vpc_security_group_ids = ["${var.security_groups}"]
   monitoring             = true
   user_data              = "${file(format("%s/user_data.sh", path.module))}"
 

dns/main.tf

@@ -40,5 +40,5 @@ output "zone_id" {
 
 // A comma separated list of the zone name servers.
 output "name_servers" {
-  value = "${join(",",aws_route53_zone.main.name_servers)}"
+  value = ["${aws_route53_zone.main.name_servers}"]
 }

ecs-cluster/main.tf

@@ -51,7 +51,8 @@ variable "key_name" {
 }
 
 variable "security_groups" {
-  description = "Comma separated list of security groups"
+  description = "List of security groups"
+  type = "list"
 }
 
 variable "iam_instance_profile" {
@@ -135,7 +136,7 @@ resource "aws_security_group" "cluster" {
     from_port       = 0
     to_port         = 0
     protocol        = -1
-    security_groups = ["${split(",", var.security_groups)}"]
+    security_groups = ["${var.security_groups}"]
   }
 
   egress {