class Arguments(object):
"""
Provides a wrapper around a list of :class:`Argument`. For example
.. code-block:: python
class PluginExample(Plugin):
arguments = PluginArguments(
PluginArgument("username",
help="The username for your account.",
metavar="EMAIL",
requires=["password"]), // requires the password too
PluginArgument("password",
sensitive=True, // should be masked in logs, etc.
help="The password for your account.",
metavar="PASSWORD")
)
This will add the ``--plugin-username`` and ``--plugin-password`` arguments to the CLI
(assuming the plugin module is ``plugin``).
"""
def __init__(self, *args):
self.arguments = OrderedDict((arg.name, arg) for arg in args)
def __iter__(self):
return iter(self.arguments.values())
def get(self, name):
return self.arguments.get(name)
def requires(self, name):
"""
Find all the arguments required by name
:param name: name of the argument the find the dependencies
:return: list of dependant arguments
"""
results = {name}
argument = self.get(name)
for reqname in argument.requires:
required = self.get(reqname)
if not required:
raise KeyError(
"{0} is not a valid argument for this plugin".format(
reqname))
if required.name in results:
raise RuntimeError("cycle detected in plugin argument config")
results.add(required.name)
yield required
for r in self.requires(required.name):
if r.name in results:
raise RuntimeError(
"cycle detected in plugin argument config")
results.add(r.name)
yield r
