tools/cli: add new arg for parent host

Parent is the machine where VMs (nested hosts) are
living. So, in the inventory we need this information
to perform snapshots on it while targetting guest hosts.

Signed-off-by: Olivier Hoareau <olivier.hoareau@vates.tech>

Author: olivierh-pro

README.md

@@ -673,6 +673,7 @@ Take a look at an example inventory file:
 
 [all]
 repositories = ["xcp-ng-base"]
+hosting_pool = "A"
 
 [hosts]
 
@@ -681,12 +682,13 @@ repositories = ["xcp-ng-base"]
 [hosts."ip_or_hostname-2"]
 
 repositories = ["xcp-ng-updates"]
+hosting_pool = "B"
 ```
 
 > [!IMPORTANT]
-> Config values under `servers` override values under `all`. For instance, the above inventory would produce
+> Config values under `hosts` override values under `all`. For instance, the above inventory would produce
 > the following python dict:
 >
-> `{'ip_or_hostname-1': {'repositories': ['xcp-ng-base']}, 'ip_or_hostname-2': {'repositories': ['xcp-ng-updates']}}`
+> `{'ip_or_hostname-1': {'repositories': ['xcp-ng-base'], 'hosting_pool': 'A'}, 'ip_or_hostname-2': {'repositories': ['xcp-ng-updates'], 'hosting_pool': 'B'}}`
 >
 > Using *enablerepo flag* `-e` with inventory is still possible, it won't be used though.

lib/tools/cli.py

@@ -17,7 +17,7 @@ def _command_update(args: argparse.Namespace) -> None:
     if args.inventory:
         inventory = load_inventory(args.inventory)
     else:
-        inventory = into_inventory(args.hosts, args.repos)
+        inventory = into_inventory(args.hosts, args.repos, args.hosting_pool)
 
     update_pools(inventory)
 
@@ -53,6 +53,12 @@ def cli() -> None:
         dest="repos",
         help="repositories to enable when updating",
     )
+    subparser_cmd_update.add_argument(
+        "-P",
+        "--hosting-pool",
+        type=HostAddress,
+        help="Address (hostname|ip) of hosting pool's master host (nested context)",
+    )
     subparser_cmd_update.set_defaults(func=_command_update)
 
     args = parser.parse_args()

lib/tools/inventory.py

@@ -11,14 +11,14 @@
 
 class HostConfig(TypedDict):
     repositories: list[str]
+    hosting_pool: HostAddress | None
 
 
 HostConfigs: TypeAlias = dict[HostAddress, HostConfig]
 
 class Inventory(TypedDict):
     hosts: HostConfigs
 
-
 def load_inventory(inventory_path: Path) -> Inventory:
     """Create an inventory object from loaded inventory file."""
     with open(inventory_path, "rb") as f:
@@ -30,22 +30,31 @@ def load_inventory(inventory_path: Path) -> Inventory:
     inventory_hosts: HostConfigs = {}
     for h, config in hosts.items():
         repos = config.get("repositories", [])
-        host: HostConfig = {"repositories": repos or all.get("repositories", [])}
+        hosting_pool = config.get("hosting_pool", None)
+        if hosting_pool is None:
+            hosting_pool = all.get("hosting_pool", None)
+        host: HostConfig = {
+            "repositories": repos or all.get("repositories", []),
+            "hosting_pool": hosting_pool,
+        }
         inventory_hosts[h] = host
 
     return {
         "hosts": inventory_hosts,
     }
 
 
-def into_inventory(hosts: list[HostAddress], repositories: list[str]) -> Inventory:
+def into_inventory(hosts: list[HostAddress], repositories: list[str], hosting_pool: HostAddress) -> Inventory:
     """Create an inventory object from arguments.
 
     Basically, it is used as compatibility when we don't want inventory from file.
     """
     inventory_hosts: HostConfigs = {}
     for h in hosts:
-        host: HostConfig = {"repositories": repositories or []}
+        host: HostConfig = {
+            "repositories": repositories or [],
+            "hosting_pool": hosting_pool or None,
+        }
         inventory_hosts[h] = host
 
     return {