install: use standard Python classes to declare knob types

Use type(None) rather than bool to define knobs which are represented as
command line flags. This allows declaring both "--option" and
"--option={0,1}"-style command line options.

Use enum.Enum subclasses instead of set literals to declare enumerations.

Use typing.List[T] instead of (list, T) to declare lists. (Note that a
minimal reimplementation of typing.List is used instead of the Python 2
backport of the typing module due to non-technical reasons.)

Use CheckedIPAddress instead of 'ip' and 'ip-local' to declare IP
addresses.

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

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

1 files changed, 16 insertions, 9 deletions

diff --git a/ipapython/install/cli.py b/ipapython/install/cli.py
index a91afe5fd..65fc9529f 100644
--- a/ipapython/install/cli.py
+++ b/ipapython/install/cli.py
@@ -7,6 +7,7 @@ Command line support.
 """
 
 import collections
+import enum
 import functools
 import optparse
 import signal
@@ -14,7 +15,7 @@ import signal
 import six
 
 from ipapython import admintool, ipa_log_manager
-from ipapython.ipautil import private_ccache
+from ipapython.ipautil import CheckedIPAddress, private_ccache
 
 from . import core, common
 
@@ -23,6 +24,8 @@ __all__ = ['install_tool', 'uninstall_tool']
 if six.PY3:
     long = int
 
+NoneType = type(None)
+
 
 def _get_usage(configurable_class):
     usage = '%prog [options]'
@@ -143,13 +146,17 @@ class ConfigureTool(admintool.AdminTool):
                     parser, "{0} options".format(group_cls.description))
 
             knob_type = knob_cls.type
-            if isinstance(knob_type, tuple):
-                knob_scalar_type = knob_type[1]
+            if issubclass(knob_type, list):
+                try:
+                    # typing.List[X].__parameters__ == (X,)
+                    knob_scalar_type = knob_type.__parameters__[0]
+                except AttributeError:
+                    knob_scalar_type = str
             else:
                 knob_scalar_type = knob_type
 
             kwargs = dict()
-            if knob_scalar_type is bool:
+            if knob_scalar_type is NoneType:
                 kwargs['type'] = None
                 kwargs['const'] = True
                 kwargs['default'] = False
@@ -159,16 +166,16 @@ class ConfigureTool(admintool.AdminTool):
                 kwargs['type'] = 'int'
             elif knob_scalar_type is long:
                 kwargs['type'] = 'long'
-            elif knob_scalar_type in ('ip', 'ip-local'):
-                kwargs['type'] = knob_scalar_type
-            elif isinstance(knob_scalar_type, set):
+            elif knob_scalar_type is CheckedIPAddress:
+                kwargs['type'] = 'ip'
+            elif issubclass(knob_scalar_type, enum.Enum):
                 kwargs['type'] = 'choice'
-                kwargs['choices'] = list(knob_scalar_type)
+                kwargs['choices'] = [i.value for i in knob_scalar_type]
             else:
                 kwargs['nargs'] = 1
                 kwargs['callback_args'] = (knob_scalar_type,)
             kwargs['dest'] = name
-            if isinstance(knob_type, tuple):
+            if issubclass(knob_type, list):
                 if 'type' not in kwargs:
                     kwargs['action'] = 'callback'
                     kwargs['callback'] = (