initial AWS terraform (#180)

* initial AWS terraform

terraform/aws/modules/instance_group/main.tf

@@ -0,0 +1,58 @@
+terraform {
+  required_providers {
+    aws = {
+      source  = "hashicorp/aws"
+      version = "~> 4.0"
+    }
+  }
+}
+
+locals {
+  name = "${var.name}-${lower(var.role)}"
+}
+
+
+resource "aws_launch_configuration" "control_plane_launch_config" {
+  name_prefix          = local.name
+  image_id             = var.image_id
+  instance_type        = var.instance_type
+  iam_instance_profile = var.iam_instance_profile
+  metadata_options {
+    http_tokens = "required"
+  }
+
+
+  lifecycle {
+    create_before_destroy = true
+  }
+}
+
+resource "aws_autoscaling_group" "control_plane_autoscaling_group" {
+  name                 = local.name
+  launch_configuration = aws_launch_configuration.control_plane_launch_config.name
+  min_size             = 1
+  max_size             = 10
+  desired_capacity     = var.instance_count
+  vpc_zone_identifier  = [var.subnetwork]
+  target_group_arns    = var.target_group_arns
+
+  lifecycle {
+    create_before_destroy = true
+  }
+
+  tag {
+    key                 = "Name"
+    value               = local.name
+    propagate_at_launch = true
+  }
+  tag {
+    key                 = "constellation-role"
+    value               = var.role
+    propagate_at_launch = true
+  }
+  tag {
+    key                 = "constellation-uid"
+    value               = var.uid
+    propagate_at_launch = true
+  }
+}

terraform/aws/modules/instance_group/variables.tf

@@ -0,0 +1,49 @@
+variable "name" {
+  type        = string
+  description = "Base name of the instance group."
+}
+
+variable "role" {
+  type        = string
+  description = "The role of the instance group. Has to be 'ControlPlane' or 'Worker'."
+}
+
+variable "uid" {
+  type        = string
+  description = "UID of the cluster. This is used for tags."
+}
+
+variable "instance_type" {
+  type        = string
+  description = "Instance type for the nodes."
+}
+
+variable "instance_count" {
+  type        = number
+  description = "Number of instances in the instance group."
+}
+
+variable "image_id" {
+  type        = string
+  description = "Image ID for the nodes."
+}
+
+variable "disk_size" {
+  type        = number
+  description = "Disk size for the nodes, in GB."
+}
+
+variable "target_group_arns" {
+  type        = list(string)
+  description = "ARN of the target group."
+}
+
+variable "subnetwork" {
+  type        = string
+  description = "Name of the subnetwork to use."
+}
+
+variable "iam_instance_profile" {
+  type        = string
+  description = "IAM instance profile for the nodes."
+}