install: fix subclassing of knob groups

Add new @group decorator to declare an installer class as a knob group
instead of subclassing Group, so that subclassing the installer does not
create duplicates of the original group.

https://fedorahosted.org/freeipa/ticket/6392

Reviewed-By: Martin Basti <mbasti@redhat.com>

ipapython/install/core.py

@@ -23,7 +23,7 @@ from . import util, typing
 from .util import from_
 
 __all__ = ['InvalidStateError', 'KnobValueError', 'Property', 'Knob',
-           'Configurable', 'Group', 'Component', 'Composite']
+           'Configurable', 'group', 'Component', 'Composite']
 
 NoneType = type(None)
 
@@ -516,11 +516,14 @@ class Configurable(six.with_metaclass(abc.ABCMeta, object)):
         self.__state = to_state
 
 
-class Group(Configurable):
-    @classmethod
-    def group(cls):
+def group(cls):
+    def group():
         return cls
 
+    cls.group = staticmethod(group)
+
+    return cls
+
 
 class ComponentMeta(util.InnerClassMeta, abc.ABCMeta):
     pass

ipaserver/install/server/common.py

@@ -12,7 +12,7 @@ import six
 from ipapython.dn import DN
 from ipapython.ipautil import CheckedIPAddress
 from ipapython.install import common, core
-from ipapython.install.core import Knob
+from ipapython.install.core import Knob, group
 from ipalib.util import validate_domain_name
 from ipaserver.install import bindinstance
 from ipapython.dnsutil import check_zone_overlap
@@ -29,7 +29,8 @@ VALID_SUBJECT_ATTRS = ['st', 'o', 'ou', 'dnqualifier', 'c',
                        'incorporationcountry', 'businesscategory']
 
 
-class BaseServerCA(common.Installable, core.Group, core.Composite):
+@group
+class BaseServerCA(common.Installable, core.Composite):
     description = "certificate system"
 
     external_ca = Knob(
@@ -160,7 +161,8 @@ class BaseServerCA(common.Installable, core.Group, core.Composite):
     )
 
 
-class BaseServerDNS(common.Installable, core.Group, core.Composite):
+@group
+class BaseServerDNS(common.Installable, core.Composite):
     description = "DNS"
 
     forwarders = Knob(

ipaserver/install/server/install.py

@@ -1138,10 +1138,6 @@ def uninstall(installer):
 
 
 class ServerCA(BaseServerCA):
-
-    # FIXME: Following Knobs are inherited because framework is not able to
-    # help groups correctly.
-
     external_ca = Knob(BaseServerCA.external_ca)
     external_ca_type = Knob(BaseServerCA.external_ca_type)
     external_cert_files = Knob(BaseServerCA.external_cert_files)
@@ -1176,12 +1172,6 @@ class ServerCA(BaseServerCA):
         cli_aliases=['pkinit_pin'],
     )
 
-    dirsrv_cert_name = Knob(BaseServerCA.dirsrv_cert_name)
-    http_cert_name = Knob(BaseServerCA.http_cert_name)
-    pkinit_cert_name = Knob(BaseServerCA.pkinit_cert_name)
-    ca_cert_files = Knob(BaseServerCA.ca_cert_files)
-    subject = Knob(BaseServerCA.subject)
-    ca_signing_algorithm = Knob(BaseServerCA.ca_signing_algorithm)
     skip_schema_check = None