Support Kolla image tags overrides per environment

etc/kayobe/kolla/globals.yml

@@ -15,7 +15,8 @@ kolla_base_distro_and_version: "{% raw %}{{ kolla_base_distro }}-{{ kolla_base_d
 # Dict of Kolla image tags to deploy for each service.
 # Each key is the tag variable prefix name, and the value is another dict,
 # where the key is the OS distro and the value is the tag to deploy.
-# NOTE: This is defined in etc/kayobe/kolla-image-tags.yml.
+# NOTE: This is loaded from etc/kayobe/kolla-image-tags.yml and optionally
+# overridden by etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla-image-tags.yml.
 kolla_image_tags:
 {{ kolla_image_tags | to_nice_yaml | indent(width=4, first=true) }}
 

tools/kolla-images.py

@@ -26,15 +26,16 @@
 import re
 import subprocess
 import sys
-from typing import Dict, List, Optional
+from typing import Dict, List, Optional, Tuple
 
 import yaml
 
 
 # Dict of Kolla image tags to deploy for each service.
 # Each key is the tag variable prefix name, and the value is another dict,
 # where the key is the OS distro and the value is the tag to deploy.
-# This is the content of etc/kayobe/kolla-image-tags.yml.
+# Tags are loaded from etc/kayobe/kolla-image-tags.yml and optionally
+# overridden by etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla-image-tags.yml.
 KollaImageTags = Dict[str, Dict[str, str]]
 
 # Maps a Kolla image to a list of containers that use the image.
@@ -151,11 +152,64 @@ def read_unbuildable_images(images_file: str) -> Dict[str, List[str]]:
     return variables["stackhpc_kolla_unbuildable_images"]
 
 
-def read_kolla_image_tags(tags_file: str) -> KollaImageTags:
-    """Read kolla image tags kolla-image-tags.yml config file."""
-    with open(get_abs_path(tags_file), "r") as f:
-        variables = yaml.safe_load(f)
-    return variables["kolla_image_tags"]
+def read_kolla_image_tags_file(tags_file: pathlib.Path) -> KollaImageTags:
+    """Read kolla image tags from a single YAML file."""
+    with tags_file.open("r") as f:
+        variables = yaml.safe_load(f) or {}
+    kolla_image_tags = variables.get("kolla_image_tags")
+    if not isinstance(kolla_image_tags, dict):
+        raise ValueError(f"Missing or invalid kolla_image_tags in {tags_file}")
+    return kolla_image_tags
+
+
+def merge_kolla_image_tags(base: KollaImageTags, override: KollaImageTags) -> KollaImageTags:
+    """Deep-merge Kolla image tags where override values take precedence."""
+    merged = {tag_var: dict(tags) for tag_var, tags in base.items()}
+    for tag_var, tags in override.items():
+        existing = merged.setdefault(tag_var, {})
+        existing.update(tags)
+    return merged
+
+
+def get_kolla_image_tag_files() -> Tuple[pathlib.Path, Optional[pathlib.Path]]:
+    """Return main and environment-specific kolla image tags files."""
+    main_tags_file = get_abs_path("etc/kayobe/kolla-image-tags.yml")
+    kayobe_environment = os.environ.get("KAYOBE_ENVIRONMENT")
+    if kayobe_environment:
+        env_tags_file = get_abs_path(f"etc/kayobe/environments/{kayobe_environment}/kolla-image-tags.yml")
+    else:
+        env_tags_file = None
+    return main_tags_file, env_tags_file
+
+
+def load_kolla_image_tags() -> KollaImageTags:
+    """Load and merge Kolla image tags from main and env-specific files."""
+    main_tags_file, env_tags_file = get_kolla_image_tag_files()
+    checked_files = [main_tags_file]
+    if env_tags_file is not None:
+        checked_files.append(env_tags_file)
+
+    loaded_files = []
+    kolla_image_tags: KollaImageTags = {}
+    for tags_file in checked_files:
+        if not tags_file.is_file():
+            continue
+        loaded_files.append(tags_file)
+        kolla_image_tags = merge_kolla_image_tags(kolla_image_tags, read_kolla_image_tags_file(tags_file))
+
+    if loaded_files:
+        return kolla_image_tags
+
+    kayobe_environment = os.environ.get("KAYOBE_ENVIRONMENT", "<unset>")
+    print("Failed to find kolla-image-tags.yml. Checked files:")
+    for tags_file in checked_files:
+        print(f"  - {tags_file}")
+    print(f"KAYOBE_ENVIRONMENT={kayobe_environment}")
+    print("Expected YAML structure:")
+    print("  kolla_image_tags:")
+    print("    openstack:")
+    print("      rocky-9: <tag>")
+    sys.exit(1)
 
 
 def get_containers(image):
@@ -405,7 +459,7 @@ def list_tag_vars(kolla_image_tags: KollaImageTags):
 
 def main():
     args = parse_args()
-    kolla_image_tags = read_kolla_image_tags("etc/kayobe/kolla-image-tags.yml")
+    kolla_image_tags = load_kolla_image_tags()
     base_distros = args.base_distros.split(",")
 
     validate(kolla_image_tags)