Rename CLC files and favor Terraform list index syntax

* Rename Container Linux Config (CLC) files to *.yaml to align
with Fedora CoreOS Config (FCC) files and for syntax highlighting
* Replace common uses of Terraform `element` (which wraps around)
with `list[index]` syntax to surface index errors

aws/container-linux/kubernetes/ami.tf

@@ -4,8 +4,8 @@ locals {
   # flatcar-stable -> Flatcar Linux AMI
   ami_id = local.flavor == "flatcar" ? data.aws_ami.flatcar.image_id : data.aws_ami.coreos.image_id
 
-  flavor  = element(split("-", var.os_image), 0)
-  channel = element(split("-", var.os_image), 1)
+  flavor  = split("-", var.os_image)[0]
+  channel = split("-", var.os_image)[1]
 }
 
 data "aws_ami" "coreos" {

aws/container-linux/kubernetes/controllers.tf

@@ -10,7 +10,7 @@ resource "aws_route53_record" "etcds" {
   ttl  = 300
 
   # private IPv4 address for etcd
-  records = [element(aws_instance.controllers.*.private_ip, count.index)]
+  records = [aws_instance.controllers.*.private_ip[count.index]]
 }
 
 # Controller instances
@@ -24,7 +24,7 @@ resource "aws_instance" "controllers" {
   instance_type = var.controller_type
 
   ami       = local.ami_id
-  user_data = element(data.ct_config.controller-ignitions.*.rendered, count.index)
+  user_data = data.ct_config.controller-ignitions.*.rendered[count.index]
 
   # storage
   root_block_device {
@@ -36,7 +36,7 @@ resource "aws_instance" "controllers" {
 
   # network
   associate_public_ip_address = true
-  subnet_id                   = element(aws_subnet.public.*.id, count.index)
+  subnet_id                   = aws_subnet.public.*.id[count.index]
   vpc_security_group_ids      = [aws_security_group.controller.id]
 
   lifecycle {
@@ -50,10 +50,7 @@ resource "aws_instance" "controllers" {
 # Controller Ignition configs
 data "ct_config" "controller-ignitions" {
   count        = var.controller_count
-  content = element(
-    data.template_file.controller-configs.*.rendered,
-    count.index,
-  )
+  content      = data.template_file.controller-configs.*.rendered[count.index]
   pretty_print = false
   snippets     = var.controller_clc_snippets
 }
@@ -62,7 +59,7 @@ data "ct_config" "controller-ignitions" {
 data "template_file" "controller-configs" {
   count = var.controller_count
 
-  template = file("${path.module}/cl/controller.yaml.tmpl")
+  template = file("${path.module}/cl/controller.yaml")
 
   vars = {
     # Cannot use cyclic dependencies on controllers or their DNS records

aws/container-linux/kubernetes/network.tf

@@ -62,6 +62,6 @@ resource "aws_route_table_association" "public" {
   count = length(data.aws_availability_zones.all.names)
 
   route_table_id = aws_route_table.default.id
-  subnet_id      = element(aws_subnet.public.*.id, count.index)
+  subnet_id      = aws_subnet.public.*.id[count.index]
 }
 

aws/container-linux/kubernetes/nlb.tf

@@ -88,7 +88,7 @@ resource "aws_lb_target_group_attachment" "controllers" {
   count = var.controller_count
 
   target_group_arn = aws_lb_target_group.controllers.arn
-  target_id        = element(aws_instance.controllers.*.id, count.index)
+  target_id        = aws_instance.controllers.*.id[count.index]
   port             = 6443
 }
 

aws/container-linux/kubernetes/workers/ami.tf

@@ -4,8 +4,8 @@ locals {
   # flatcar-stable -> Flatcar Linux AMI
   ami_id = local.flavor == "flatcar" ? data.aws_ami.flatcar.image_id : data.aws_ami.coreos.image_id
 
-  flavor  = element(split("-", var.os_image), 0)
-  channel = element(split("-", var.os_image), 1)
+  flavor  = split("-", var.os_image)[0]
+  channel = split("-", var.os_image)[1]
 }
 
 data "aws_ami" "coreos" {

aws/container-linux/kubernetes/workers/workers.tf

@@ -78,7 +78,7 @@ data "ct_config" "worker-ignition" {
 
 # Worker Container Linux config
 data "template_file" "worker-config" {
-  template = file("${path.module}/cl/worker.yaml.tmpl")
+  template = file("${path.module}/cl/worker.yaml")
 
   vars = {
     kubeconfig             = indent(10, var.kubeconfig)

azure/container-linux/kubernetes/controllers.tf

@@ -11,16 +11,13 @@ resource "azurerm_dns_a_record" "etcds" {
   ttl  = 300
 
   # private IPv4 address for etcd
-  records = [element(
-    azurerm_network_interface.controllers.*.private_ip_address,
-    count.index,
-  )]
+  records = [azurerm_network_interface.controllers.*.private_ip_address[count.index]]
 }
 
 locals {
   # Channel for a Container Linux derivative
   # coreos-stable -> Container Linux Stable
-  channel = element(split("-", var.os_image), 1)
+  channel = split("-", var.os_image)[1]
 }
 
 # Controller availability set to spread controllers
@@ -63,12 +60,12 @@ resource "azurerm_virtual_machine" "controllers" {
   }
 
   # network
-  network_interface_ids = [element(azurerm_network_interface.controllers.*.id, count.index)]
+  network_interface_ids = [azurerm_network_interface.controllers.*.id[count.index]]
 
   os_profile {
     computer_name  = "${var.cluster_name}-controller-${count.index}"
     admin_username = "core"
-    custom_data    = element(data.ct_config.controller-ignitions.*.rendered, count.index)
+    custom_data    = data.ct_config.controller-ignitions.*.rendered[count.index]
   }
 
   # Azure mandates setting an ssh_key, even though Ignition custom_data handles it too
@@ -108,7 +105,7 @@ resource "azurerm_network_interface" "controllers" {
     private_ip_address_allocation = "dynamic"
 
     # public IPv4
-    public_ip_address_id = element(azurerm_public_ip.controllers.*.id, count.index)
+    public_ip_address_id = azurerm_public_ip.controllers.*.id[count.index]
   }
 }
 
@@ -135,10 +132,7 @@ resource "azurerm_public_ip" "controllers" {
 # Controller Ignition configs
 data "ct_config" "controller-ignitions" {
   count        = var.controller_count
-  content = element(
-    data.template_file.controller-configs.*.rendered,
-    count.index,
-  )
+  content      = data.template_file.controller-configs.*.rendered[count.index]
   pretty_print = false
   snippets     = var.controller_clc_snippets
 }
@@ -147,7 +141,7 @@ data "ct_config" "controller-ignitions" {
 data "template_file" "controller-configs" {
   count = var.controller_count
 
-  template = file("${path.module}/cl/controller.yaml.tmpl")
+  template = file("${path.module}/cl/controller.yaml")
 
   vars = {
     # Cannot use cyclic dependencies on controllers or their DNS records

azure/container-linux/kubernetes/ssh.tf

@@ -45,7 +45,7 @@ resource "null_resource" "bootstrap" {
 
   connection {
     type    = "ssh"
-    host    = element(azurerm_public_ip.controllers.*.ip_address, 0)
+    host    = azurerm_public_ip.controllers.*.ip_address[0]
     user    = "core"
     timeout = "15m"
   }

azure/container-linux/kubernetes/workers/workers.tf

@@ -1,7 +1,7 @@
 locals {
   # Channel for a Container Linux derivative
   # coreos-stable -> Container Linux Stable
-  channel = element(split("-", var.os_image), 1)
+  channel = split("-", var.os_image)[1]
 }
 
 # Workers scale set
@@ -104,7 +104,7 @@ data "ct_config" "worker-ignition" {
 
 # Worker Container Linux configs
 data "template_file" "worker-config" {
-  template = file("${path.module}/cl/worker.yaml.tmpl")
+  template = file("${path.module}/cl/worker.yaml")
 
   vars = {
     kubeconfig             = indent(10, var.kubeconfig)

bare-metal/container-linux/kubernetes/profiles.tf

@@ -31,7 +31,7 @@ resource "matchbox_profile" "container-linux-install" {
 data "template_file" "container-linux-install-configs" {
   count = length(var.controllers) + length(var.workers)
 
-  template = file("${path.module}/cl/install.yaml.tmpl")
+  template = file("${path.module}/cl/install.yaml")
 
   vars = {
     os_flavor          = local.flavor
@@ -72,7 +72,7 @@ resource "matchbox_profile" "cached-container-linux-install" {
 data "template_file" "cached-container-linux-install-configs" {
   count = length(var.controllers) + length(var.workers)
 
-  template = file("${path.module}/cl/install.yaml.tmpl")
+  template = file("${path.module}/cl/install.yaml")
 
   vars = {
     os_flavor          = local.flavor
@@ -150,7 +150,7 @@ data "ct_config" "controller-ignitions" {
 data "template_file" "controller-configs" {
   count = length(var.controllers)
 
-  template = file("${path.module}/cl/controller.yaml.tmpl")
+  template = file("${path.module}/cl/controller.yaml")
 
   vars = {
     domain_name            = var.controllers.*.domain[count.index]
@@ -180,7 +180,7 @@ data "ct_config" "worker-ignitions" {
 data "template_file" "worker-configs" {
   count = length(var.workers)
 
-  template = file("${path.module}/cl/worker.yaml.tmpl")
+  template = file("${path.module}/cl/worker.yaml")
 
   vars = {
     domain_name            = var.workers.*.domain[count.index]

digital-ocean/container-linux/kubernetes/controllers.tf

@@ -11,7 +11,7 @@ resource "digitalocean_record" "controllers" {
   ttl  = 300
 
   # IPv4 addresses of controllers
-  value = element(digitalocean_droplet.controllers.*.ipv4_address, count.index)
+  value = digitalocean_droplet.controllers.*.ipv4_address[count.index]
 }
 
 # Discrete DNS records for each controller's private IPv4 for etcd usage
@@ -27,7 +27,7 @@ resource "digitalocean_record" "etcds" {
   ttl  = 300
 
   # private IPv4 address for etcd
-  value = element(digitalocean_droplet.controllers.*.ipv4_address_private, count.index)
+  value = digitalocean_droplet.controllers.*.ipv4_address_private[count.index]
 }
 
 # Controller droplet instances
@@ -44,7 +44,7 @@ resource "digitalocean_droplet" "controllers" {
   ipv6               = true
   private_networking = true
 
-  user_data = element(data.ct_config.controller-ignitions.*.rendered, count.index)
+  user_data = data.ct_config.controller-ignitions.*.rendered[count.index]
   ssh_keys  = var.ssh_fingerprints
 
   tags = [
@@ -64,7 +64,7 @@ resource "digitalocean_tag" "controllers" {
 # Controller Ignition configs
 data "ct_config" "controller-ignitions" {
   count        = var.controller_count
-  content      = element(data.template_file.controller-configs.*.rendered, count.index)
+  content      = data.template_file.controller-configs.*.rendered[count.index]
   pretty_print = false
   snippets     = var.controller_clc_snippets
 }
@@ -73,7 +73,7 @@ data "ct_config" "controller-ignitions" {
 data "template_file" "controller-configs" {
   count = var.controller_count
 
-  template = file("${path.module}/cl/controller.yaml.tmpl")
+  template = file("${path.module}/cl/controller.yaml")
 
   vars = {
     # Cannot use cyclic dependencies on controllers or their DNS records

digital-ocean/container-linux/kubernetes/workers.tf

@@ -8,7 +8,7 @@ resource "digitalocean_record" "workers-record-a" {
   name  = "${var.cluster_name}-workers"
   type  = "A"
   ttl   = 300
-  value = element(digitalocean_droplet.workers.*.ipv4_address, count.index)
+  value = digitalocean_droplet.workers.*.ipv4_address[count.index]
 }
 
 resource "digitalocean_record" "workers-record-aaaa" {
@@ -20,7 +20,7 @@ resource "digitalocean_record" "workers-record-aaaa" {
   name  = "${var.cluster_name}-workers"
   type  = "AAAA"
   ttl   = 300
-  value = element(digitalocean_droplet.workers.*.ipv6_address, count.index)
+  value = digitalocean_droplet.workers.*.ipv6_address[count.index]
 }
 
 # Worker droplet instances
@@ -63,7 +63,7 @@ data "ct_config" "worker-ignition" {
 
 # Worker Container Linux config
 data "template_file" "worker-config" {
-  template = file("${path.module}/cl/worker.yaml.tmpl")
+  template = file("${path.module}/cl/worker.yaml")
 
   vars = {
     cluster_dns_service_ip = cidrhost(var.service_cidr, 10)

google-cloud/container-linux/kubernetes/controllers.tf

@@ -11,7 +11,7 @@ resource "google_dns_record_set" "etcds" {
   ttl  = 300
 
   # private IPv4 address for etcd
-  rrdatas = [element(google_compute_instance.controllers.*.network_interface.0.network_ip, count.index)]
+  rrdatas = [google_compute_instance.controllers.*.network_interface.0.network_ip[count.index]]
 }
 
 # Zones in the region
@@ -30,11 +30,12 @@ resource "google_compute_instance" "controllers" {
   count = var.controller_count
 
   name = "${var.cluster_name}-controller-${count.index}"
+  # use a zone in the region and wrap around (e.g. controllers > zones)
   zone         = element(local.zones, count.index)
   machine_type = var.controller_type
 
   metadata = {
-    user-data = element(data.ct_config.controller-ignitions.*.rendered, count.index)
+    user-data = data.ct_config.controller-ignitions.*.rendered[count.index]
   }
 
   boot_disk {
@@ -65,10 +66,7 @@ resource "google_compute_instance" "controllers" {
 # Controller Ignition configs
 data "ct_config" "controller-ignitions" {
   count        = var.controller_count
-  content = element(
-    data.template_file.controller-configs.*.rendered,
-    count.index,
-  )
+  content      = data.template_file.controller-configs.*.rendered[count.index]
   pretty_print = false
   snippets     = var.controller_clc_snippets
 }
@@ -77,7 +75,7 @@ data "ct_config" "controller-ignitions" {
 data "template_file" "controller-configs" {
   count = var.controller_count
 
-  template = file("${path.module}/cl/controller.yaml.tmpl")
+  template = file("${path.module}/cl/controller.yaml")
 
   vars = {
     # Cannot use cyclic dependencies on controllers or their DNS records

google-cloud/container-linux/kubernetes/workers/workers.tf

@@ -78,7 +78,7 @@ data "ct_config" "worker-ignition" {
 
 # Worker Container Linux config
 data "template_file" "worker-config" {
-  template = file("${path.module}/cl/worker.yaml.tmpl")
+  template = file("${path.module}/cl/worker.yaml")
 
   vars = {
     kubeconfig             = indent(10, var.kubeconfig)