terraform-aws-eks/workers_launch_template.tf

# Worker Groups using Launch Templates

resource "aws_autoscaling_group" "workers_launch_template" {
  count = local.worker_group_launch_template_count
  name_prefix = "${aws_eks_cluster.this.name}-${lookup(
    var.worker_groups_launch_template[count.index],
    "name",
    count.index,
  )}"
  desired_capacity = lookup(
    var.worker_groups_launch_template[count.index],
    "asg_desired_capacity",
    local.workers_group_defaults["asg_desired_capacity"],
  )
  max_size = lookup(
    var.worker_groups_launch_template[count.index],
    "asg_max_size",
    local.workers_group_defaults["asg_max_size"],
  )
  min_size = lookup(
    var.worker_groups_launch_template[count.index],
    "asg_min_size",
    local.workers_group_defaults["asg_min_size"],
  )
  force_delete = lookup(
    var.worker_groups_launch_template[count.index],
    "asg_force_delete",
    local.workers_group_defaults["asg_force_delete"],
  )
  target_group_arns = lookup(
    var.worker_groups_launch_template[count.index],
    "target_group_arns",
    local.workers_group_defaults["target_group_arns"]
  )
  service_linked_role_arn = lookup(
    var.worker_groups_launch_template[count.index],
    "service_linked_role_arn",
    local.workers_group_defaults["service_linked_role_arn"],
  )
  vpc_zone_identifier = lookup(
    var.worker_groups_launch_template[count.index],
    "subnets",
    local.workers_group_defaults["subnets"]
  )
  protect_from_scale_in = lookup(
    var.worker_groups_launch_template[count.index],
    "protect_from_scale_in",
    local.workers_group_defaults["protect_from_scale_in"],
  )
  suspended_processes = lookup(
    var.worker_groups_launch_template[count.index],
    "suspended_processes",
    local.workers_group_defaults["suspended_processes"]
  )
  enabled_metrics = lookup(
    var.worker_groups_launch_template[count.index],
    "enabled_metrics",
    local.workers_group_defaults["enabled_metrics"]
  )
  placement_group = lookup(
    var.worker_groups_launch_template[count.index],
    "placement_group",
    local.workers_group_defaults["placement_group"],
  )
  termination_policies = lookup(
    var.worker_groups_launch_template[count.index],
    "termination_policies",
    local.workers_group_defaults["termination_policies"]
  )

  launch_template {
    id = aws_launch_template.workers_launch_template.*.id[count.index]
    version = lookup(
      var.worker_groups_launch_template[count.index],
      "launch_template_version",
      local.workers_group_defaults["launch_template_version"],
    )
  }

  tags = concat(
    [
      {
        "key" = "Name"
        "value" = "${aws_eks_cluster.this.name}-${lookup(
          var.worker_groups_launch_template[count.index],
          "name",
          count.index,
        )}-eks_asg"
        "propagate_at_launch" = true
      },
      {
        "key"                 = "kubernetes.io/cluster/${aws_eks_cluster.this.name}"
        "value"               = "owned"
        "propagate_at_launch" = true
      },
      {
        "key" = "k8s.io/cluster-autoscaler/${lookup(
          var.worker_groups_launch_template[count.index],
          "autoscaling_enabled",
          local.workers_group_defaults["autoscaling_enabled"],
        ) ? "enabled" : "disabled"}"
        "value"               = "true"
        "propagate_at_launch" = false
      },
      {
        "key"                 = "k8s.io/cluster-autoscaler/${aws_eks_cluster.this.name}"
        "value"               = aws_eks_cluster.this.name
        "propagate_at_launch" = false
      },
      {
        "key" = "k8s.io/cluster-autoscaler/node-template/resources/ephemeral-storage"
        "value" = "${lookup(
          var.worker_groups_launch_template[count.index],
          "root_volume_size",
          local.workers_group_defaults["root_volume_size"],
        )}Gi"
        "propagate_at_launch" = false
      },
    ],
    local.asg_tags,
    lookup(
      var.worker_groups_launch_template[count.index],
      "tags",
      local.workers_group_defaults["tags"]
    )
  )

  lifecycle {
    create_before_destroy = true
    ignore_changes        = [desired_capacity]
  }
}

resource "aws_launch_template" "workers_launch_template" {
  count = local.worker_group_launch_template_count
  name_prefix = "${aws_eks_cluster.this.name}-${lookup(
    var.worker_groups_launch_template[count.index],
    "name",
    count.index,
  )}"

  network_interfaces {
    associate_public_ip_address = lookup(
      var.worker_groups_launch_template[count.index],
      "public_ip",
      local.workers_group_defaults["public_ip"],
    )
    delete_on_termination = lookup(
      var.worker_groups_launch_template[count.index],
      "eni_delete",
      local.workers_group_defaults["eni_delete"],
    )
    security_groups = flatten([
      local.worker_security_group_id,
      var.worker_additional_security_group_ids,
      lookup(
        var.worker_groups_launch_template[count.index],
        "additional_security_group_ids",
        local.workers_group_defaults["additional_security_group_ids"],
      ),
    ])
  }

  iam_instance_profile {
    name = coalescelist(
      aws_iam_instance_profile.workers_launch_template.*.name,
      data.aws_iam_instance_profile.custom_worker_group_launch_template_iam_instance_profile.*.name,
    )[count.index]
  }

  image_id = lookup(
    var.worker_groups_launch_template[count.index],
    "ami_id",
    local.workers_group_defaults["ami_id"],
  )
  instance_type = lookup(
    var.worker_groups_launch_template[count.index],
    "instance_type",
    local.workers_group_defaults["instance_type"],
  )
  key_name = lookup(
    var.worker_groups_launch_template[count.index],
    "key_name",
    local.workers_group_defaults["key_name"],
  )
  user_data = base64encode(
    data.template_file.launch_template_userdata.*.rendered[count.index],
  )
  ebs_optimized = lookup(
    var.worker_groups_launch_template[count.index],
    "ebs_optimized",
    lookup(
      local.ebs_optimized,
      lookup(
        var.worker_groups_launch_template[count.index],
        "instance_type",
        local.workers_group_defaults["instance_type"],
      ),
      false,
    ),
  )

  credit_specification {
    cpu_credits = lookup(
      var.worker_groups_launch_template[count.index],
      "cpu_credits",
      local.workers_group_defaults["cpu_credits"]
    )
  }

  monitoring {
    enabled = lookup(
      var.worker_groups_launch_template[count.index],
      "enable_monitoring",
      local.workers_group_defaults["enable_monitoring"],
    )
  }

  placement {
    tenancy = lookup(
      var.worker_groups_launch_template[count.index],
      "launch_template_placement_tenancy",
      local.workers_group_defaults["launch_template_placement_tenancy"],
    )
    group_name = lookup(
      var.worker_groups_launch_template[count.index],
      "launch_template_placement_group",
      local.workers_group_defaults["launch_template_placement_group"],
    )
  }

  block_device_mappings {
    device_name = lookup(
      var.worker_groups_launch_template[count.index],
      "root_block_device_name",
      local.workers_group_defaults["root_block_device_name"],
    )

    ebs {
      volume_size = lookup(
        var.worker_groups_launch_template[count.index],
        "root_volume_size",
        local.workers_group_defaults["root_volume_size"],
      )
      volume_type = lookup(
        var.worker_groups_launch_template[count.index],
        "root_volume_type",
        local.workers_group_defaults["root_volume_type"],
      )
      iops = lookup(
        var.worker_groups_launch_template[count.index],
        "root_iops",
        local.workers_group_defaults["root_iops"],
      )
      encrypted = lookup(
        var.worker_groups_launch_template[count.index],
        "root_encrypted",
        local.workers_group_defaults["root_encrypted"],
      )
      kms_key_id = lookup(
        var.worker_groups_launch_template[count.index],
        "root_kms_key_id",
        local.workers_group_defaults["root_kms_key_id"],
      )
      delete_on_termination = true
    }
  }

  tag_specifications {
    resource_type = "volume"

    tags = merge(
      {
        "Name" = "${aws_eks_cluster.this.name}-${lookup(
          var.worker_groups_launch_template[count.index],
          "name",
          count.index,
        )}-eks_asg"
      },
      var.tags,
    )
  }

  tags = var.tags

  lifecycle {
    create_before_destroy = true
  }
}

resource "aws_iam_instance_profile" "workers_launch_template" {
  count       = var.manage_worker_iam_resources ? local.worker_group_launch_template_count : 0
  name_prefix = aws_eks_cluster.this.name
  role = lookup(
    var.worker_groups_launch_template[count.index],
    "iam_role_id",
    local.workers_group_defaults["iam_role_id"],
  )
  path = var.iam_path
}