Merge branch 'feat/add-iaas-image-selection' into staging

Author: garloff

user-docs/usage-hints/find-image/find_img.py

@@ -6,7 +6,7 @@
 #
 # (c) Kurt Garloff <[email protected]>, 7/2025
 # SPDX-License-Identifier: MIT
-"This module finds the a vanilla distribution image"
+"This module finds the a distribution image with a given purpose"
 
 import os
 import sys

user-docs/usage-hints/find-image/find_img.tf

@@ -1,5 +1,7 @@
 #!/usr/bin/env tofu apply -auto-approve
 # Pass variables with -var os_purpose=minimal
+# (c) Kurt Garloff <[email protected]>
+# SPDX-License-Identifier: MIT
 
 variable "os_distro" {
   type    = string
@@ -26,17 +28,20 @@ terraform {
 }
 
 provider "openstack" {
-  # Your cloud config (or use environment variables OS_CLOUD)
+  # Your cloud config (or use environment variable OS_CLOUD)
 }
 
 data "openstack_images_image_v2" "my_image" {
   most_recent = true
-  
+
   properties = {
-    os_distro        = "${var.os_distro}"
-    os_version       = "${var.os_version}"
-    os_purpose       = "${var.os_purpose}"
+    os_distro	  = "${var.os_distro}"
+    os_version    = "${var.os_version}"
+    os_purpose    = "${var.os_purpose}"
   }
+  #sort           = "name:desc,created_at:desc"
+  #sort_key       = "name"
+  #sort_direction = "desc"
 }
 
 # Output the results for inspection

user-docs/usage-hints/find-image/find_img2.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python3
+#
+# find_img2.py
+#
+# Find images for opentofu/terraform
+#
+# (c) Kurt Garloff <[email protected]>, 11/2025
+# SPDX-License-Identifier: MIT
+"This module finds the a distribution image with a given purpose"
+
+import sys
+import json
+import find_img
+
+try:
+    in_data = json.loads(sys.stdin.read())
+    conn = find_img.openstack.connect()  # cloud=os.environ["OS_CLOUD"])
+    images = find_img.find_image(conn, in_data["os_distro"], in_data["os_version"], in_data["os_purpose"])
+    for img in images:
+        print(f"DEBUG: {img[0]} {img[1]}", file=sys.stderr)
+    if not (len(images)):
+        print(f"No image found for {in_data}", file=sys.stderr)
+        sys.exit(1)
+    output = { "image_id": images[0][0],
+               "image_name": images[0][1] }
+    print(json.dumps(output))
+
+except Exception as e:
+    print(f"Error: {str(e)}", file=sys.stderr)
+    sys.exit(2)

user-docs/usage-hints/find-image/find_img2.tf

@@ -0,0 +1,52 @@
+#!/usr/bin/env tofu apply -auto-approve
+# Pass variables with -var os_purpose=minimal
+# (c) Kurt Garloff <[email protected]>
+# SPDX-License-Identifier: MIT
+
+variable "os_distro2" {
+  type    = string
+  default = "ubuntu"
+}
+
+variable "os_version2" {
+  type    = string
+  default = "24.04"
+}
+
+variable "os_purpose2" {
+  type    = string
+  default = "generic"
+}
+
+#terraform {
+#  required_providers {
+#    openstack = {
+#      source  = "terraform-provider-openstack/openstack"
+#      version = "~> 1.54.0"
+#    }
+#  }
+#}
+
+#provider "openstack" {
+#  # Your cloud config (or use environment variables OS_CLOUD)
+#}
+
+# Call python find_img.py to find best image
+data "external" "my_image2" {
+  program = ["python3", "${path.module}/find_img2.py"]
+
+  query = {
+    os_distro        = "${var.os_distro2}"
+    os_version       = "${var.os_version2}"
+    os_purpose       = "${var.os_purpose2}"
+  }
+}
+
+# Output the results for inspection
+output "selected_image2" {
+  value = {
+    id   = data.external.my_image2.result.image_id
+    name = data.external.my_image2.result.image_name
+  }
+}
+

user-docs/usage-hints/find-image/index.md

@@ -125,8 +125,9 @@ data "openstack_images_image_v2" "my_image" {
     os_version      = "24.04"
     os_purpose      = "generic"
   }
-  # sort_key        = "name"
-  # sort_direction  = "desc"
+  # sort             = "name:desc,created_at:desc"
+  # sort_key          = "name"
+  # sort_direction    = "desc"
 }
 
 # Use the selected image
@@ -138,11 +139,63 @@ resource "openstack_compute_instance_v2" "instance" {
 
 This will find the most recent image wtih the `os_` variables set to `ubuntu`, `24.04`, `generic`.
 Note that unlike the python and shell examples, we can not easily sort for name and creation
-date at the same time; the name sorting is thus commented out here. To use name sorting you can
-enable it — using it and then selecting the latest if the name is identical requires some
-HCL magic using `locals` and `reverse(sort(...))` calls or calling an external program.
+date at the same time; the only option to deal with several matches is to tell opentofu's
+openstack provider to return the latest (the one with the newest `created_at` date).
 
 An example can be found in [find_img.tf](find_img.tf). Call it with `tofu apply -auto-approve`
 (after you ran `tofu init` in this directory once).
 
-The fallback to name matching is harder.
+The fallback to name matching for clouds that don't have `os_purpose` yet is harder.
+
+We use an external program, the python script from before to select the right image and just create
+a little wrapper around it: [find_img2.py](find_img2.py). The HCL then looks like this:
+
+```hcl
+# Call python find_img.py to find best image
+data "external" "my_image2" {
+  program = ["python3", "${path.module}/find_img2.py"]
+
+  query = {
+    os_distro        = "${var.os_distro2}"
+    os_version       = "${var.os_version2}"
+    os_purpose       = "${var.os_purpose2}"
+  }
+}
+
+# Output the results for inspection
+output "selected_image2" {
+  value = {
+    id   = data.external.my_image2.result.image_id
+    name = data.external.my_image2.result.image_name
+  }
+}
+```
+
+Note that I have appended a `2` to the variable names, so they don't clash in case you have the
+original example in the same directory.
+
+## heat
+
+I did not find a good way to select an image based on its properties in heat.
+Obviously, you can use the python (or shell) script above and pass the image name
+or ID as a parameter when invoking heat.
+
+```yaml
+heat_template_version: 2018-08-31
+
+parameters:
+  image:
+    type: string
+    description: Image ID or name
+    constraints:
+      - custom_constraint: glance.image
+
+resources:
+  my_instance:
+    type: OS::Nova::Server
+    properties:
+      image: { get_param: image }
+      # ... other properties
+```
+
+and call `openstack stack create --parameter image=$ID $TEMPLATE $STACKNAME`.