AWS nodes and user-data created from config map.

example.tfvars

@@ -1,4 +1,4 @@
-vm-name-prefix = "docker-ansible-test"
+vm-name-prefix = "k8s-tf"
 
 # A CIDR block ending in '/32' equates to a single IP address, '0.0.0.0/0'
 # equates to any ip address.
@@ -13,6 +13,10 @@ worker-nodes = 2
 node-memory = 2048
 node-vcpus = 2
 
+################################################################################
+# AWS EC2 instance types
+################################################################################
+
 # 1 GiB, 1 vcpu, only one that is free.
 # This one won't work with k8s because it requires at least 2 vcpus.
 aws-ec2-instance-type = "t2.micro"
@@ -20,6 +24,19 @@ aws-ec2-instance-type = "t2.micro"
 # 4 GiB, 2 vcpus
 # aws-ec2-instnce-type = "t2.medium"
 
+################################################################################
+
+nodes-config = {
+  "master" = {
+    base-image = "ami-0dd0ccab7e2801812"
+    num = 1
+  },
+  "worker" = {
+    base-image = "ami-0dd0ccab7e2801812"
+    num = 2
+  }
+}
+
 ################################################################################
 # AWS images (AMIs)
 ################################################################################
@@ -53,6 +70,10 @@ base-image = "ami-0dd0ccab7e2801812"
 # From https://cloud.centos.org/centos/7/images/ from	2020-11-12 06:52
 # base-image = "https://cloud.centos.org/centos/7/images/CentOS-7-x86_64-GenericCloud-2009.qcow2"
 
+################################################################################
+# Keys/Passwords
+################################################################################
+
 # Password hash created with:
 # python3 -c 'import crypt; print(crypt.crypt("linux", crypt.mksalt(crypt.METHOD_SHA512)))'
 # where "linux" is the password.

main.tf

@@ -1,8 +1,8 @@
 terraform {
-  required_version = ">= 0.13"
+  required_version = ">= 1.0.8"
   required_providers {
     libvirt = {
-      source = "dmacvicar/libvirt"
+      source  = "dmacvicar/libvirt"
       version = "0.6.11"
     }
   }
@@ -12,24 +12,14 @@ terraform {
 # cloud-init
 ################################################################################
 
-data "template_file" "master-node-user-datas" {
-  template = file("${path.module}/cloud_init.cfg")
-  vars = {
-    admin-passwd  = "${var.root-admin-passwd}"
-    admin-pub-key = "${var.root-admin-pub-key}"
-    hostname      = "${var.vm-name-prefix}-master-${count.index}"
-  }
-  count = var.master-nodes
-}
-
-data "template_file" "worker-node-user-datas" {
-  template = file("${path.module}/cloud_init.cfg")
-  vars = {
-    admin-passwd  = "${var.root-admin-passwd}"
-    admin-pub-key = "${var.root-admin-pub-key}"
-    hostname      = "${var.vm-name-prefix}-worker-${count.index}"
-  }
-  count = var.worker-nodes
+module "cloud-init-config" {
+  for_each            = var.nodes-config
+  source              = "./modules/cloud-init-config"
+  cloud-init-template = "${path.module}/cloud_init.cfg"
+  hostname-prefix     = "${var.vm-name-prefix}-${each.key}"
+  num                 = each.value.num
+  root-admin-passwd   = var.root-admin-passwd
+  root-admin-pub-key  = var.root-admin-pub-key
 }
 
 ################################################################################
@@ -42,16 +32,20 @@ provider "aws" {
   region = "us-east-2"
 }
 
-module "aws-amis" {
-  source = "./modules/aws-amis"
-}
+# This module will grab the latest ami for a variety of distros.
+# module "aws-amis" {
+#   source = "./modules/aws-amis"
+# }
+# output "amis" {
+#   value = module.aws-amis.amis
+# }
 
 module "aws-network" {
-  source = "./modules/aws-network"
-  name-prefix = var.vm-name-prefix
-  vpc-cidr-block = var.aws-vpc-cidr-block
+  source            = "./modules/aws-network"
+  name-prefix       = var.vm-name-prefix
+  vpc-cidr-block    = var.aws-vpc-cidr-block
   subnet-cidr-block = var.aws-subnet-cidr-block
-  admin-ips = var.admin-ips
+  admin-ips         = var.admin-ips
 }
 
 # This key pair is not actually used. Keys are added to the nodes via cloud-init
@@ -64,30 +58,16 @@ resource "aws_key_pair" "key" {
   }
 }
 
-module "master-nodes" {
+module "nodes" {
+  for_each           = var.nodes-config
   source             = "./modules/aws-nodes"
-  ami                = var.base-image
+  ami                = each.value.base-image
   ec2-instance-type  = var.aws-ec2-instance-type
   subnet-id          = module.aws-network.subnet.id
   security-group-ids = [module.aws-network.default-security-group.id]
-  user-datas         = data.template_file.master-node-user-datas
-  num-nodes          = var.master-nodes
-  name-prefix        = "${var.vm-name-prefix}-master"
-}
-
-module "worker-nodes" {
-  source             = "./modules/aws-nodes"
-  ami                = var.base-image
-  ec2-instance-type  = var.aws-ec2-instance-type
-  subnet-id          = module.aws-network.subnet.id
-  security-group-ids = [module.aws-network.default-security-group.id]
-  user-datas         = data.template_file.worker-node-user-datas
-  num-nodes          = var.worker-nodes
-  name-prefix        = "${var.vm-name-prefix}-worker"
-}
-
-output "amis" {
-  value = module.aws-amis.amis
+  user-datas         = lookup(module.cloud-init-config, each.key, null).user-datas
+  num-nodes          = each.value.num
+  name-prefix        = "${var.vm-name-prefix}-${each.key}"
 }
 
 ################################################################################
@@ -142,11 +122,6 @@ output "amis" {
 # end libvirt
 ################################################################################
 
-# TODO REM move to other file?
-output "master-ips" {
-  value = module.master-nodes.ips
-}
-
-output "worker-ips" {
-  value = module.worker-nodes.ips
+output "ips" {
+  value = { for type, node in module.nodes : type => node.ips }
 }

modules/cloud-init-config/main.tf

@@ -0,0 +1,9 @@
+data "template_file" "user-datas" {
+  template = file("${var.cloud-init-template}")
+  vars = {
+    admin-passwd  = "${var.root-admin-passwd}"
+    admin-pub-key = "${var.root-admin-pub-key}"
+    hostname      = "${var.hostname-prefix}-${count.index}"
+  }
+  count = var.num
+}

modules/cloud-init-config/outputs.tf

@@ -0,0 +1,3 @@
+output "user-datas" {
+  value = data.template_file.user-datas
+}

modules/cloud-init-config/variables.tf

@@ -0,0 +1,22 @@
+variable "cloud-init-template" {
+  default     = "../../cloud_init.cfg"
+  description = "The path to the cloud-init config template."
+  type        = string
+}
+
+variable "hostname-prefix" {
+  description = "This prefix wil be applied as a prefix for the hostnames."
+}
+
+variable "num" {
+  description = "The number of user-datas to create with these parameters."
+}
+
+variable "root-admin-passwd" {
+  description = "This value will be substituted for any occurence of 'admin-password' in the cloud-init config template."
+}
+
+variable "root-admin-pub-key" {
+  description = "This value will be substituted for any occurence of 'admin-pub-key' in the cloud-init config template."
+}
+

variables.tf

@@ -43,6 +43,11 @@ variable "node-vcpus" {
   type        = number
 }
 
+variable "nodes-config" {
+  description = "A config that declares how many nodes of each type you want created."
+  type = map(object({base-image=string,num=number}))
+}
+
 variable "root-admin-passwd" {
   description = "This will be the password for the root and admin user. The format of this can by any format accepted by cloud-init's chpasswd module."
 }