fix(examples): Update AMI filter (#1673)

- Updated AMI filter to select the latest instead of the latest in 2012
- Add commented examples for AMI and ephemeral to ubuntu example

Author: npalm

Diff for: examples/ephemeral/main.tf

@@ -66,7 +66,7 @@ module "runners" {
 
   # configure your pre-built AMI
   # enabled_userdata = false
-  # ami_filter       = { name = ["github-runner-amzn2-x86_64-2021*"] }
+  # ami_filter       = { name = ["github-runner-amzn2-x86_64-*"] }
   # ami_owners       = [data.aws_caller_identity.current.account_id]
 
   # Enable logging

Diff for: examples/prebuilt/variables.tf

@@ -10,10 +10,10 @@ variable "runner_os" {
 
 variable "ami_name_filter" {
   type    = string
-  default = "github-runner-amzn2-x86_64-2021*"
+  default = "github-runner-amzn2-x86_64-*"
 }
 
 variable "aws_region" {
   type    = string
   default = "eu-west-1"
-}
+}

Diff for: examples/ubuntu/main.tf

@@ -7,6 +7,8 @@ resource "random_id" "random" {
   byte_length = 20
 }
 
+data "aws_caller_identity" "current" {}
+
 module "runners" {
   source = "../../"
 
@@ -35,14 +37,25 @@ module "runners" {
   # enable access to the runners via SSM
   enable_ssm_on_runners = true
 
-  runner_run_as     = "ubuntu"
+  runner_run_as = "ubuntu"
+
+  # AMI selection and userdata
+  #
+  # option 1. configure your pre-built AMI + userdata
   userdata_template = "./templates/user-data.sh"
   ami_owners        = ["099720109477"] # Canonical's Amazon account ID
 
   ami_filter = {
     name = ["ubuntu/images/hvm-ssd/ubuntu-focal-20.04-amd64-server-*"]
   }
 
+  # Custom build AMI, no custom userdata needed.
+  # option 2: Build custom AMI see ../../images/ubuntu-focal
+  #           disable lines above (option 1) and enable the ones below
+  # ami_filter = { name = ["github-runner-ubuntu-focal-amd64-*"] }
+  # ami_owners = [data.aws_caller_identity.current.account_id]
+
+
   block_device_mappings = {
     # Set the block device name for Ubuntu root device
     device_name = "/dev/sda1"
@@ -69,6 +82,11 @@ module "runners" {
     }
   ]
 
+  # Uncomment to enable ephemeral runners
+  # delay_webhook_event      = 0
+  # enable_ephemeral_runners = true
+  # enabled_userdata         = false
+
   # Uncommet idle config to have idle runners from 9 to 5 in time zone Amsterdam
   # idle_config = [{
   #   cron      = "* * 9-17 * * *"