Add a proper _get_parent_domain

src/yunohost/dns.py

@@ -40,6 +40,8 @@ from yunohost.domain import (
     domain_config_get,
     _get_domain_settings,
     _set_domain_settings,
+    _get_parent_domain_of,
+    _list_subdomains_of,
 )
 from yunohost.utils.dns import dig, is_yunohost_dyndns_domain, is_special_use_tld
 from yunohost.utils.error import YunohostValidationError, YunohostError
@@ -107,18 +109,6 @@ def domain_dns_suggest(domain):
     return result
 
 
-def _list_subdomains_of(parent_domain):
-
-    _assert_domain_exists(parent_domain)
-
-    out = []
-    for domain in domain_list()["domains"]:
-        if domain.endswith(f".{parent_domain}"):
-            out.append(domain)
-
-    return out
-
-
 def _build_dns_conf(base_domain, include_empty_AAAA_if_no_ipv6=False):
     """
     Internal function that will returns a data structure containing the needed

src/yunohost/domain.py

@@ -105,6 +105,33 @@ def _assert_domain_exists(domain):
         raise YunohostValidationError("domain_name_unknown", domain=domain)
 
 
+def _list_subdomains_of(parent_domain):
+
+    _assert_domain_exists(parent_domain)
+
+    out = []
+    for domain in domain_list()["domains"]:
+        if domain.endswith(f".{parent_domain}"):
+            out.append(domain)
+
+    return out
+
+
+def _get_parent_domain_of(domain):
+
+    _assert_domain_exists(domain)
+
+    if "." not in domain:
+        return domain
+
+    parent_domain = domain.split(".", 1)[-1]
+    if parent_domain not in domain_list()["domains"]:
+        return domain  # Domain is its own parent
+
+    else:
+        return _get_parent_domain_of(parent_domain)
+
+
 @is_unit_operation()
 def domain_add(operation_logger, domain, dyndns=False):
     """