Updated the packer example to use HCL

Author: dmattia

packer-example/simple-web-server.json

@@ -3,8 +3,8 @@
     "region": "us-east-2"
   },
   "builders": [{
-    "ami_name": "gruntwork-packer-training-rails-{{isotime | clean_ami_name}}",
-    "ami_description": "An Ubuntu AMI that with Ruby on Rails installed.",
+    "ami_name": "gruntwork-packer-training-rails-{{isotime | clean_resource_name}}",
+    "ami_description": "An Ubuntu AMI that has Ruby on Rails installed.",
     "instance_type": "t2.micro",
     "region": "{{user `region`}}",
     "type": "amazon-ebs",

packer-example/simple-web-server.pkr.hcl

@@ -0,0 +1,55 @@
+variable "region" {
+  description = "The AWS Region to launch the AMI builder in"
+  default     = "us-east-2"
+}
+
+source "amazon-ebs" "ubuntu" {
+  ami_name        = "gruntwork-packer-training-rails-hcl-{{isotime | clean_resource_name}}"
+  ami_description = "An Ubuntu AMI that has Ruby on RIls installed"
+  region          = var.region
+  instance_type   = "t2.micro"
+
+  source_ami_filter {
+    filters = {
+      virtualization-type = "hvm"
+      architecture        = "x86_64"
+      name                = "*ubuntu-xenial-16.04-amd64-server-*"
+      root-device-type    = "ebs"
+    }
+    owners      = ["099720109477"]
+    most_recent = true
+  }
+  communicator = "ssh"
+  ssh_username = "ubuntu"
+}
+
+build {
+  sources = ["source.amazon-ebs.ubuntu"]
+
+  provisioner "shell" {
+    inline = [
+      "echo 'Sleeping for 30 seconds to give Ubuntu enough time to initialize (otherwise, packages may fail to install).'",
+      "sleep 30"
+    ]
+  }
+
+  provisioner "shell" {
+    # TODO: Use `template_dir` once implemented for HCL:
+    # https://github.com/hashicorp/packer/issues/9176
+    script = "./install-rails.sh"
+  }
+
+  provisioner "file" {
+    # TODO: Use `template_dir` once implemented for HCL:
+    # https://github.com/hashicorp/packer/issues/9176
+    source = "../example-rails-app"
+    destination = "/home/ubuntu"
+  }
+
+  provisioner "shell" {
+    inline = [
+      "cd /home/ubuntu/example-rails-app",
+      "bundle install"
+    ]
+  }
+}