411 lines
14 KiB
Python
411 lines
14 KiB
Python
# -*- coding: utf-8 -*- #
|
|
# Copyright 2017 Google LLC. All Rights Reserved.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
"""Classes to handle dependencies for concepts.
|
|
|
|
At runtime, resources can be parsed and initialized using the information given
|
|
in the Deps object. All the information given by the user in the command line is
|
|
available in the Deps object. It may also access other information (such as
|
|
information provided by the user during a prompt or properties that are changed
|
|
during runtime before the Deps object is used) when Get() is called for a given
|
|
attribute, depending on the fallthroughs.
|
|
"""
|
|
|
|
from __future__ import absolute_import
|
|
from __future__ import division
|
|
from __future__ import unicode_literals
|
|
|
|
import abc
|
|
|
|
from googlecloudsdk.calliope.concepts import util
|
|
from googlecloudsdk.core import exceptions
|
|
from googlecloudsdk.core import properties
|
|
from googlecloudsdk.core import resources
|
|
|
|
|
|
class Error(exceptions.Error):
|
|
"""Base exception type for this module."""
|
|
|
|
|
|
class FallthroughNotFoundError(Error):
|
|
"""Raised when an attribute value is not found by a Fallthrough object."""
|
|
|
|
|
|
class AttributeNotFoundError(Error, AttributeError):
|
|
"""Raised when an attribute value cannot be found by a Deps object."""
|
|
|
|
|
|
class _FallthroughBase(object, metaclass=abc.ABCMeta):
|
|
"""Represents a way to get information about a concept's attribute.
|
|
|
|
Specific implementations of Fallthrough objects must implement the method:
|
|
|
|
_Call():
|
|
Get a value from information given to the fallthrough.
|
|
|
|
GetValue() is used by the Deps object to attempt to find the value of an
|
|
attribute. The hint property is used to provide an informative error when an
|
|
attribute can't be found.
|
|
"""
|
|
|
|
def __init__(self, hint, active=False, plural=False):
|
|
"""Initializes a fallthrough to an arbitrary function.
|
|
|
|
Args:
|
|
hint: str | list[str], The user-facing message for the fallthrough
|
|
when it cannot be resolved.
|
|
active: bool, True if the fallthrough is considered to be "actively"
|
|
specified, i.e. on the command line.
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
resource argument is plural (i.e. parses to a list).
|
|
"""
|
|
self._hint = hint
|
|
self.active = active
|
|
self.plural = plural
|
|
|
|
def GetValue(self, parsed_args):
|
|
"""Gets a value from information given to the fallthrough.
|
|
|
|
Args:
|
|
parsed_args: the argparse namespace.
|
|
|
|
Raises:
|
|
FallthroughNotFoundError: If the attribute is not found.
|
|
|
|
Returns:
|
|
The value of the attribute.
|
|
"""
|
|
value = self._Call(parsed_args)
|
|
if value:
|
|
return self._Pluralize(value)
|
|
raise FallthroughNotFoundError()
|
|
|
|
@abc.abstractmethod
|
|
def _Call(self, parsed_args):
|
|
pass
|
|
|
|
def _Pluralize(self, value):
|
|
"""Pluralize the result of calling the fallthrough. May be overridden."""
|
|
if not self.plural or isinstance(value, list):
|
|
return value
|
|
return [value] if value else []
|
|
|
|
@property
|
|
def hint(self):
|
|
"""String representation of the fallthrough for user-facing messaging."""
|
|
return self._hint
|
|
|
|
def __hash__(self):
|
|
return hash(self.hint) + hash(self.active)
|
|
|
|
def __eq__(self, other):
|
|
return (isinstance(other, self.__class__) and other.hint == self.hint and
|
|
other.active == self.active and other.plural == self.plural)
|
|
|
|
|
|
class Fallthrough(_FallthroughBase):
|
|
"""A fallthrough that can get an attribute value from an arbitrary function."""
|
|
|
|
def __init__(self, function, hint, active=False, plural=False):
|
|
"""Initializes a fallthrough to an arbitrary function.
|
|
|
|
Args:
|
|
function: f() -> value, A no argument function that returns the value of
|
|
the argument or None if it cannot be resolved.
|
|
hint: str, The user-facing message for the fallthrough when it cannot be
|
|
resolved. Should start with a lower-case letter.
|
|
active: bool, True if the fallthrough is considered to be "actively"
|
|
specified, i.e. on the command line.
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
resource argument is plural (i.e. parses to a list).
|
|
|
|
Raises:
|
|
ValueError: if no hint is provided
|
|
"""
|
|
if not hint:
|
|
raise ValueError('Hint must be provided.')
|
|
super(Fallthrough, self).__init__(hint, active=active, plural=plural)
|
|
self._function = function
|
|
|
|
def _Call(self, parsed_args):
|
|
del parsed_args
|
|
return self._function()
|
|
|
|
def __eq__(self, other):
|
|
return (super(Fallthrough, self).__eq__(other) and
|
|
other._function == self._function) # pylint: disable=protected-access
|
|
|
|
def __hash__(self):
|
|
return hash(self._function)
|
|
|
|
|
|
class ValueFallthrough(_FallthroughBase):
|
|
"""Gets an attribute from a property."""
|
|
|
|
def __init__(self, value, hint=None, active=False, plural=False):
|
|
"""Initializes a fallthrough for the property associated with the attribute.
|
|
|
|
Args:
|
|
value: str, Denoting the fixed value to provide to the attribute.
|
|
hint: str, Optional, If provided, used over default help_text.
|
|
active: bool, Optional, whether the value is specified by the user on
|
|
the command line.
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
resource argument is plural (i.e. parses to a list).
|
|
"""
|
|
hint = 'The default is `{}`'.format(value) if hint is None else hint
|
|
|
|
super(ValueFallthrough, self).__init__(hint, active=active, plural=plural)
|
|
self.value = value
|
|
|
|
def _Call(self, parsed_args):
|
|
del parsed_args # Not used.
|
|
return self.value
|
|
|
|
def __eq__(self, other):
|
|
if not isinstance(other, self.__class__):
|
|
return False
|
|
return other.value == self.value
|
|
|
|
def __hash__(self):
|
|
return hash(self.value)
|
|
|
|
|
|
class PropertyFallthrough(_FallthroughBase):
|
|
"""Gets an attribute from a property."""
|
|
|
|
def __init__(self, prop, plural=False):
|
|
"""Initializes a fallthrough for the property associated with the attribute.
|
|
|
|
Args:
|
|
prop: googlecloudsdk.core.properties._Property, a property.
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
resource argument is plural (i.e. parses to a list).
|
|
"""
|
|
hint = 'set the property `{}`'.format(prop)
|
|
|
|
super(PropertyFallthrough, self).__init__(hint, plural=plural)
|
|
self.property = prop
|
|
|
|
def _Call(self, parsed_args):
|
|
del parsed_args # Not used.
|
|
try:
|
|
return self.property.GetOrFail()
|
|
except (properties.InvalidValueError, properties.RequiredPropertyError):
|
|
return None
|
|
|
|
def __eq__(self, other):
|
|
if not isinstance(other, self.__class__):
|
|
return False
|
|
return other.property == self.property
|
|
|
|
def __hash__(self):
|
|
return hash(self.property)
|
|
|
|
|
|
class ArgFallthrough(_FallthroughBase):
|
|
"""Gets an attribute from the argparse parsed values for that arg."""
|
|
|
|
def __init__(self, arg_name, plural=False):
|
|
"""Initializes a fallthrough for the argument associated with the attribute.
|
|
|
|
Args:
|
|
arg_name: str, the name of the flag or positional.
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
resource argument is plural (i.e. parses to a list).
|
|
"""
|
|
super(ArgFallthrough, self).__init__(
|
|
'provide the argument `{}` on the command line'.format(arg_name),
|
|
active=True,
|
|
plural=plural)
|
|
self.arg_name = arg_name
|
|
|
|
def _Call(self, parsed_args):
|
|
arg_value = getattr(parsed_args, util.NamespaceFormat(self.arg_name), None)
|
|
return arg_value
|
|
|
|
def _Pluralize(self, value):
|
|
if not self.plural:
|
|
# Positional arguments will always be stored in argparse as lists, even if
|
|
# nargs=1. If not supposed to be plural, transform into a single value.
|
|
if isinstance(value, list):
|
|
return value[0] if value else None
|
|
return value
|
|
if value and not isinstance(value, list):
|
|
return [value]
|
|
return value if value else []
|
|
|
|
def __eq__(self, other):
|
|
if not isinstance(other, self.__class__):
|
|
return False
|
|
return other.arg_name == self.arg_name
|
|
|
|
def __hash__(self):
|
|
return hash(self.arg_name)
|
|
|
|
|
|
class FullySpecifiedAnchorFallthrough(_FallthroughBase):
|
|
"""A fallthrough that gets a parameter from the value of the anchor."""
|
|
|
|
def __init__(self,
|
|
fallthroughs,
|
|
collection_info,
|
|
parameter_name,
|
|
plural=False):
|
|
"""Initializes a fallthrough getting a parameter from the anchor.
|
|
|
|
For anchor arguments which can be plural, returns the list.
|
|
|
|
Args:
|
|
fallthroughs: list[_FallthroughBase], any fallthrough for an anchor arg.
|
|
collection_info: the info of the collection to parse the anchor as.
|
|
parameter_name: str, the name of the parameter
|
|
plural: bool, whether the expected result should be a list. Should be
|
|
False for everything except the "anchor" arguments in a case where a
|
|
"""
|
|
if plural:
|
|
hint_suffix = 'with fully specified names'
|
|
else:
|
|
hint_suffix = 'with a fully specified name'
|
|
|
|
hint = [f'{f.hint} {hint_suffix}' for f in fallthroughs]
|
|
active = all(f.active for f in fallthroughs)
|
|
super(FullySpecifiedAnchorFallthrough, self).__init__(
|
|
hint, active=active, plural=plural)
|
|
self.parameter_name = parameter_name
|
|
self.collection_info = collection_info
|
|
self._fallthroughs = tuple(fallthroughs) # Make list immutable
|
|
self._resources = resources.REGISTRY.Clone()
|
|
self._resources.RegisterApiByName(self.collection_info.api_name,
|
|
self.collection_info.api_version)
|
|
|
|
def _GetFromAnchor(self, anchor_value):
|
|
"""Returns the parameter value from the parsed anchor resource."""
|
|
try:
|
|
resource_ref = self._resources.Parse(
|
|
anchor_value, collection=self.collection_info.full_name,
|
|
api_version=self.collection_info.api_version)
|
|
except resources.Error:
|
|
return None
|
|
# This should only be called for final parsing when the anchor attribute
|
|
# has been split up into non-plural fallthroughs; thus, if an AttributeError
|
|
# results from the parser being passed a list, skip it for now.
|
|
except AttributeError:
|
|
return None
|
|
return getattr(resource_ref, self.parameter_name, None)
|
|
|
|
def _Call(self, parsed_args):
|
|
try:
|
|
anchor_value = GetFromFallthroughs(
|
|
self._fallthroughs, parsed_args, attribute_name=self.parameter_name)
|
|
except AttributeNotFoundError:
|
|
return None
|
|
return self._GetFromAnchor(anchor_value)
|
|
|
|
def __eq__(self, other):
|
|
return (isinstance(other, self.__class__) and
|
|
other._fallthroughs == self._fallthroughs and
|
|
other.collection_info == self.collection_info and
|
|
other.parameter_name == self.parameter_name)
|
|
|
|
def __hash__(self):
|
|
return sum(
|
|
map(hash, [
|
|
self._fallthroughs,
|
|
str(self.collection_info),
|
|
self.parameter_name
|
|
]))
|
|
|
|
|
|
def Get(attribute_name, attribute_to_fallthroughs_map, parsed_args=None):
|
|
"""Gets the value of an attribute based on fallthrough information.
|
|
|
|
If the attribute value is not provided by any of the fallthroughs, an
|
|
error is raised with a list of ways to provide information about the
|
|
attribute.
|
|
|
|
Args:
|
|
attribute_name: str, the name of the attribute.
|
|
attribute_to_fallthroughs_map: {str: [_FallthroughBase], a map of attribute
|
|
names to lists of fallthroughs.
|
|
parsed_args: a parsed argparse namespace.
|
|
|
|
Returns:
|
|
the value of the attribute.
|
|
|
|
Raises:
|
|
AttributeNotFoundError: if no value can be found.
|
|
"""
|
|
fallthroughs = attribute_to_fallthroughs_map.get(attribute_name, [])
|
|
return GetFromFallthroughs(
|
|
fallthroughs, parsed_args, attribute_name=attribute_name)
|
|
|
|
|
|
def GetFromFallthroughs(fallthroughs, parsed_args, attribute_name=None):
|
|
"""Gets the value of an attribute based on fallthrough information.
|
|
|
|
If the attribute value is not provided by any of the fallthroughs, an
|
|
error is raised with a list of ways to provide information about the
|
|
attribute.
|
|
|
|
Args:
|
|
fallthroughs: [_FallthroughBase], list of fallthroughs.
|
|
parsed_args: a parsed argparse namespace.
|
|
attribute_name: str, the name of the attribute. Used for error message,
|
|
omitted if not provided.
|
|
|
|
Returns:
|
|
the value of the attribute.
|
|
|
|
Raises:
|
|
AttributeNotFoundError: if no value can be found.
|
|
"""
|
|
for fallthrough in fallthroughs:
|
|
try:
|
|
return fallthrough.GetValue(parsed_args)
|
|
except FallthroughNotFoundError:
|
|
continue
|
|
|
|
hints = GetHints(fallthroughs)
|
|
|
|
fallthroughs_summary = '\n'.join(
|
|
['- {}'.format(hint) for hint in hints])
|
|
raise AttributeNotFoundError(
|
|
'Failed to find attribute{}. The attribute can be set in the '
|
|
'following ways: \n{}'.format(
|
|
'' if attribute_name is None else ' [{}]'.format(attribute_name),
|
|
fallthroughs_summary))
|
|
|
|
|
|
def GetHints(fallthroughs):
|
|
"""Gathers deduped hints from list of fallthroughs."""
|
|
# Create list of non-repeating hints. Dictionary preserves order.
|
|
# This is needed when more than one fallthrough has the same hint.
|
|
# Usually occurs for FullySpecifiedFallthroughs with different
|
|
# resource collections.
|
|
hints_set = {}
|
|
for f in fallthroughs:
|
|
new_hints = f.hint if isinstance(f.hint, list) else [f.hint]
|
|
for hint in new_hints:
|
|
if hint in hints_set:
|
|
continue
|
|
hints_set[hint] = True
|
|
|
|
return list(hints_set.keys())
|