Added frontend.LocalOrRemote command base class for commands like env

ipalib/__init__.py

@@ -873,7 +873,8 @@ freeIPA.org:
 
 import plugable
 from backend import Backend, Context
-from frontend import Command, Object, Method, Property, Application
+from frontend import Command, LocalOrRemote, Application
+from frontend import Object, Method, Property
 from ipa_types import Bool, Int, Unicode, Enum
 from frontend import Param, DefaultFrom
 

ipalib/frontend.py

@@ -782,6 +782,37 @@ class Command(plugable.Plugin):
             yield arg
 
 
+class LocalOrRemote(Command):
+    """
+    A command that is explicitly executed locally or remotely.
+
+    This is for commands that makes sense to execute either locally or
+    remotely to return a perhaps different result.  The best example of
+    this is the `ipalib.plugins.f_misc.env` plugin which returns the
+    key/value pairs describing the configuration state: it can be
+    """
+
+    takes_options = (
+        Param('server', type=ipa_types.Bool(), default=False,
+            doc='Forward to server instead of running locally',
+        ),
+    )
+
+    def run(self, *args, **options):
+        """
+        Dispatch to forward() or execute() based on ``server`` option.
+
+        When running in a client context, this command is executed remotely if
+        ``options['server']`` is true; otherwise it is executed locally.
+
+        When running in a server context, this command is always executed
+        locally and the value of ``options['server']`` is ignored.
+        """
+        if options['server'] and not self.env.in_server:
+            return self.forward(*args, **options)
+        return self.execute(*args, **options)
+
+
 class Object(plugable.Plugin):
     __public__ = frozenset((
         'backend',

tests/test_ipalib/test_frontend.py

@@ -22,7 +22,7 @@ Test the `ipalib.frontend` module.
 """
 
 from tests.util import raises, getitem, no_set, no_del, read_only
-from tests.util import check_TypeError, ClassChecker
+from tests.util import check_TypeError, ClassChecker, get_api
 from ipalib import frontend, backend, plugable, errors, ipa_types, config
 
 
@@ -796,6 +796,60 @@ class test_Command(ClassChecker):
         assert o.run.im_func is my_cmd.forward.im_func
 
 
+class test_LocalOrRemote(ClassChecker):
+    """
+    Test the `ipalib.frontend.LocalOrRemote` class.
+    """
+    _cls = frontend.LocalOrRemote
+
+    def test_init(self):
+        """
+        Test the `ipalib.frontend.LocalOrRemote.__init__` method.
+        """
+        o = self.cls()
+        o.finalize()
+        assert list(o.args) == []
+        assert list(o.options) == ['server']
+        op = o.options.server
+        assert op.required is True
+        assert op.default is False
+
+    def test_run(self):
+        """
+        Test the `ipalib.frontend.LocalOrRemote.run` method.
+        """
+        class example(self.cls):
+            takes_args = ['key?']
+
+            def forward(self, *args, **options):
+                return ('forward', args, options)
+
+            def execute(self, *args, **options):
+                return ('execute', args, options)
+
+        # Test when in_server=False:
+        (api, home) = get_api(in_server=False)
+        api.register(example)
+        api.finalize()
+        cmd = api.Command.example
+        assert cmd() == ('execute', (None,), dict(server=False))
+        assert cmd('var') == ('execute', (u'var',), dict(server=False))
+        assert cmd(server=True) == ('forward', (None,), dict(server=True))
+        assert cmd('var', server=True) == \
+            ('forward', (u'var',), dict(server=True))
+
+        # Test when in_server=True (should always call execute):
+        (api, home) = get_api(in_server=True)
+        api.register(example)
+        api.finalize()
+        cmd = api.Command.example
+        assert cmd() == ('execute', (None,), dict(server=False))
+        assert cmd('var') == ('execute', (u'var',), dict(server=False))
+        assert cmd(server=True) == ('execute', (None,), dict(server=True))
+        assert cmd('var', server=True) == \
+            ('execute', (u'var',), dict(server=True))
+
+
 class test_Object(ClassChecker):
     """
     Test the `ipalib.frontend.Object` class.