Fix for "" AMI ID error in PR 115 (#117)

* Fix for "" AMI ID

* update changelog

Author: max-rocket-internet

CHANGELOG.md

@@ -9,14 +9,13 @@ project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
-- A useful addition (slam dunk, @self 🔥)
 - add support for [`amazon-eks-node-*` AMI with bootstrap script](https://aws.amazon.com/blogs/opensource/improvements-eks-worker-node-provisioning/) (by @erks)
-- expose `kubelet_extra_args` worker group option (replacing `kubelet_node_labels`) to allow specifying arbitrary kubelet options (e.g. taints and labels) (by @erks) 
+- expose `kubelet_extra_args` worker group option (replacing `kubelet_node_labels`) to allow specifying arbitrary kubelet options (e.g. taints and labels) (by @erks)
 
 ### Changed
 
-- A subtle but thoughtful change. (Boomshakalaka, @self 🏀)
 - allow a custom AMI to be specified as a default (by @erks)
+- Bugfix for above change (by @max-rocket-internet)
 - **Breaking change** Removed support for `eks-worker-*` AMI. The cluster specifying a custom AMI based off of `eks-worker-*` AMI will have to rebuild the AMI from `amazon-eks-node-*`.  (by @erks)
 - **Breaking change** Removed `kubelet_node_labels` worker group option in favor of `kubelet_extra_args`. (by @erks)
 

local.tf

@@ -9,25 +9,25 @@ locals {
   kubeconfig_name          = "${var.kubeconfig_name == "" ? "eks_${var.cluster_name}" : var.kubeconfig_name}"
 
   workers_group_defaults_defaults = {
-    name                 = "count.index" # Name of the worker group. Literal count.index will never be used but if name is not set, the count.index interpolation will be used.
-    ami_id               = ""            # AMI ID for the eks workers. If none is provided, Terraform will search for the latest version of their EKS optimized worker AMI.
-    asg_desired_capacity = "1"           # Desired worker capacity in the autoscaling group.
-    asg_max_size         = "3"           # Maximum worker capacity in the autoscaling group.
-    asg_min_size         = "1"           # Minimum worker capacity in the autoscaling group.
-    instance_type        = "m4.large"    # Size of the workers instances.
-    spot_price           = ""            # Cost of spot instance.
-    root_volume_size     = "100"         # root volume size of workers instances.
-    root_volume_type     = "gp2"         # root volume type of workers instances, can be 'standard', 'gp2', or 'io1'
-    root_iops            = "0"           # The amount of provisioned IOPS. This must be set with a volume_type of "io1".
-    key_name             = ""            # The key name that should be used for the instances in the autoscaling group
-    pre_userdata         = ""            # userdata to pre-append to the default userdata.
-    additional_userdata  = ""            # userdata to append to the default userdata.
-    ebs_optimized        = true          # sets whether to use ebs optimization on supported types.
-    enable_monitoring    = true          # Enables/disables detailed monitoring.
-    public_ip            = false         # Associate a public ip address with a worker
-    kubelet_extra_args   = ""            # This string is passed directly to kubelet if set. Useful for adding labels or taints.
-    subnets              = ""            # A comma delimited string of subnets to place the worker nodes in. i.e. subnet-123,subnet-456,subnet-789
-    autoscaling_enabled  = false         # Sets whether policy and matching tags will be added to allow autoscaling.
+    name                 = "count.index"                   # Name of the worker group. Literal count.index will never be used but if name is not set, the count.index interpolation will be used.
+    ami_id               = "${data.aws_ami.eks_worker.id}" # AMI ID for the eks workers. If none is provided, Terraform will search for the latest version of their EKS optimized worker AMI.
+    asg_desired_capacity = "1"                             # Desired worker capacity in the autoscaling group.
+    asg_max_size         = "3"                             # Maximum worker capacity in the autoscaling group.
+    asg_min_size         = "1"                             # Minimum worker capacity in the autoscaling group.
+    instance_type        = "m4.large"                      # Size of the workers instances.
+    spot_price           = ""                              # Cost of spot instance.
+    root_volume_size     = "100"                           # root volume size of workers instances.
+    root_volume_type     = "gp2"                           # root volume type of workers instances, can be 'standard', 'gp2', or 'io1'
+    root_iops            = "0"                             # The amount of provisioned IOPS. This must be set with a volume_type of "io1".
+    key_name             = ""                              # The key name that should be used for the instances in the autoscaling group
+    pre_userdata         = ""                              # userdata to pre-append to the default userdata.
+    additional_userdata  = ""                              # userdata to append to the default userdata.
+    ebs_optimized        = true                            # sets whether to use ebs optimization on supported types.
+    enable_monitoring    = true                            # Enables/disables detailed monitoring.
+    public_ip            = false                           # Associate a public ip address with a worker
+    kubelet_extra_args   = ""                              # This string is passed directly to kubelet if set. Useful for adding labels or taints.
+    subnets              = ""                              # A comma delimited string of subnets to place the worker nodes in. i.e. subnet-123,subnet-456,subnet-789
+    autoscaling_enabled  = false                           # Sets whether policy and matching tags will be added to allow autoscaling.
   }
 
   workers_group_defaults = "${merge(local.workers_group_defaults_defaults, var.workers_group_defaults)}"

workers.tf

@@ -26,7 +26,7 @@ resource "aws_launch_configuration" "workers" {
   associate_public_ip_address = "${lookup(var.worker_groups[count.index], "public_ip", lookup(local.workers_group_defaults, "public_ip"))}"
   security_groups             = ["${local.worker_security_group_id}"]
   iam_instance_profile        = "${aws_iam_instance_profile.workers.id}"
-  image_id                    = "${lookup(var.worker_groups[count.index], "ami_id", lookup(local.workers_group_defaults, "ami_id", data.aws_ami.eks_worker.id))}"
+  image_id                    = "${lookup(var.worker_groups[count.index], "ami_id", lookup(local.workers_group_defaults, "ami_id"))}"
   instance_type               = "${lookup(var.worker_groups[count.index], "instance_type", lookup(local.workers_group_defaults, "instance_type"))}"
   key_name                    = "${lookup(var.worker_groups[count.index], "key_name", lookup(local.workers_group_defaults, "key_name"))}"
   user_data_base64            = "${base64encode(element(data.template_file.userdata.*.rendered, count.index))}"