From 88e52b581f8ce5b6dd3b898f084770b9693e1570 Mon Sep 17 00:00:00 2001
From: Dom Del Nano <ddelnano@gmail.com>
Date: Sun, 26 Feb 2023 19:57:21 -0800
Subject: [PATCH 1/2] Update the ubuntu example to be resilient to ISO releases

---
 README.md                           |  2 +-
 examples/ubuntu/ubuntu-2004.pkr.hcl | 25 ++++++++++++++++++++++---
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index bd6511d..ccb31f0 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ If you are using an older version of packer or are still using json templates yo
 ## Developing the builder
 
 ### Dependencies
-* Packer >= v1.7.1 (https://packer.io)
+* Packer >= v1.8.x (https://packer.io)
 * XenServer / Citrix Hypervisor > 7.6
 * Golang 1.16
 
diff --git a/examples/ubuntu/ubuntu-2004.pkr.hcl b/examples/ubuntu/ubuntu-2004.pkr.hcl
index 67238ff..d4b03ff 100644
--- a/examples/ubuntu/ubuntu-2004.pkr.hcl
+++ b/examples/ubuntu/ubuntu-2004.pkr.hcl
@@ -7,6 +7,25 @@ packer {
   }
 }
 
+# This local determines what Ubuntu iso URL and sha256 hash we lookup. Updating
+# this will allow a new version to be pulled in.
+local "ubuntu_version" {
+  expression = "22.04"
+}
+
+
+data "http" "ubuntu_sha_and_release" {
+  url = "https://releases.ubuntu.com/22.04/SHA256SUMS"
+}
+
+local "ubuntu_sha256" {
+  expression = regex("([A-Za-z0-9]+)[\\s\\*]+ubuntu-.*server", data.http.ubuntu_sha_and_release.body)
+}
+
+local "ubuntu_url_path" {
+  expression = regex("[A-Za-z0-9]+[\\s\\*]+ubuntu-${local.ubuntu_version}.(\\d+)-live-server-amd64.iso", data.http.ubuntu_sha_and_release.body)
+}
+
 variable "remote_host" {
   type        = string
   description = "The ip or fqdn of your XenServer. This will be pulled from the env var 'PKR_VAR_XAPI_HOST'"
@@ -48,9 +67,9 @@ locals {
 
 
 source "xenserver-iso" "ubuntu-2004" {
-  iso_checksum      = "5035be37a7e9abbdc09f0d257f3e33416c1a0fb322ba860d42d74aa75c3468d4"
+  iso_checksum      = local.ubuntu_sha256.0
   iso_checksum_type = "sha256"
-  iso_url           = "http://releases.ubuntu.com/20.04/ubuntu-20.04.5-live-server-amd64.iso"
+  iso_url           = "https://releases.ubuntu.com/22.04/ubuntu-22.04.${local.ubuntu_url_path.0}-live-server-amd64.iso"
 
   sr_iso_name    = var.sr_iso_name
   sr_name        = var.sr_name
@@ -65,7 +84,7 @@ source "xenserver-iso" "ubuntu-2004" {
   vm_name        = "packer-ubuntu-2004-${local.timestamp}"
   vm_description = "Build started: ${local.timestamp}"
   vm_memory      = 4096
-  disk_size      = 20000
+  disk_size      = 30720
 
   floppy_files = [
     "examples/http/ubuntu-2004/meta-data",

From 69bae007b670566bb874bee04b98e03266cf620d Mon Sep 17 00:00:00 2001
From: Dom Del Nano <ddelnano@gmail.com>
Date: Sun, 26 Feb 2023 20:04:39 -0800
Subject: [PATCH 2/2] Update the correct README doc with the packer 1.8
 requirement

---
 README.md          | 2 +-
 examples/README.md | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index ccb31f0..bd6511d 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ If you are using an older version of packer or are still using json templates yo
 ## Developing the builder
 
 ### Dependencies
-* Packer >= v1.8.x (https://packer.io)
+* Packer >= v1.7.1 (https://packer.io)
 * XenServer / Citrix Hypervisor > 7.6
 * Golang 1.16
 
diff --git a/examples/README.md b/examples/README.md
index ede7545..c19d589 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -7,7 +7,8 @@ In order to see an exhaustive list of configuration options for the packer build
 ### Running the examples
 
 In order to run the examples you will need to perform the following steps:
-1. Export those vars:
+1. Install packer 1.8 or later (the Ubuntu example requires the `http` data source)
+2. Export those vars:
 ```
 PKR_VAR_remote_host
 PKR_VAR_remote_password
@@ -17,9 +18,9 @@ PKR_VAR_sr_iso_name
 ``` 
 `PKR_VAR_remote_host` must be the resource pool primary, aka the master.
 
-2. Run `packer init path/to/defenition.pkr.hcl` to download the xenserver plugin
+3. Run `packer init path/to/defenition.pkr.hcl` to download the xenserver plugin
 
-2. Run `packer build  path/to/defenition.pkr.hcl`   
+4. Run `packer build  path/to/defenition.pkr.hcl`   
 so for example:
 `packer build  examples/centos/centos8-netinstall.pkr.hcl`