Some fixes

modoboa/admin/api/v2/serializers.py

@@ -246,12 +246,8 @@ class AdminGlobalParametersSerializer(serializers.Serializer):
 
     # Aliases settings
     alias_can_target_any_domain = serializers.BooleanField(default=True)
-    alias_target_block_list = serializers.ListField(
-        child=serializers.CharField(), required=False
-    )
-    alias_target_allow_list = serializers.ListField(
-        child=serializers.CharField(), required=False
-    )
+    alias_target_block_list = serializers.CharField(required=False, allow_null=True)
+    alias_target_allow_list = serializers.CharField(required=False, allow_null=True)
 
     def validate_default_domain_quota(self, value):
         """Ensure quota is a positive integer."""

modoboa/admin/models/alias.py

@@ -91,16 +91,21 @@ class AliasManager(models.Manager):
         )
 
 
+def convert_to_list(raw_value: str) -> list[str]:
+    """Convert input string to list of string."""
+    return [item.strip() for item in raw_value.split(",")]
+
+
 def is_alias_target_allowed(domain: str) -> bool:
     """Check if alias target is allowed or not."""
     params = dict(param_tools.get_global_parameters(app="admin"))
     if params.get("alias_can_target_any_domain"):
-        blocked_domains = params.get("alias_target_block_list", "").split(",")
-        if domain in blocked_domains:
+        blocked_domains = params.get("alias_target_block_list")
+        if blocked_domains and domain in convert_to_list(blocked_domains):
             return False
     else:
-        allowed_domains = params.get("alias_target_allow_list", "").split(",")
-        if domain not in allowed_domains:
+        allowed_domains = params.get("alias_target_allow_list")
+        if allowed_domains and domain not in convert_to_list(allowed_domains):
             return False
     return True