ironic-lib/ironic_lib/capabilities.py
Dmitry Tantsur 67de2e90b6 Move some generic functions from IPA
This change exposes existing or copies from IPA functions that are
potentially common between ironic, IPA and ironic-lib itself:
1) utils.try_execute
2) disk_utils.udev_settle, partprobe and trigger_device_rescan
3) capabilities parsing and re-combining

Change-Id: I0ab42e082e8003415a1cac857d1c4b2044c5484d
2020-08-24 11:12:01 +02:00

121 lines
4.8 KiB
Python

# 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.
"""Code for working with capabilities."""
import json
import logging
from ironic_lib.common.i18n import _
LOG = logging.getLogger(__name__)
def _parse_old_format(cap_str, skip_malformed=True):
"""Extract capabilities from string.
:param cap_str: A string in the key1:value1,key2:value2 format.
:param skip_malformed: Whether to skip malformed items or raise ValueError.
:return: a dictionary
"""
capabilities = {}
for node_capability in cap_str.split(','):
parts = node_capability.split(':', 1)
if len(parts) == 2 and parts[0] and parts[1]:
capabilities[parts[0]] = parts[1]
else:
if skip_malformed:
LOG.warning("Ignoring malformed capability '%s'. "
"Format should be 'key:val'.", node_capability)
else:
raise ValueError(
_("Malformed capability %s. Format should be 'key:val'")
% node_capability)
return capabilities
def parse(capabilities, compat=True, skip_malformed=False):
"""Extract capabilities from provided object.
The capabilities value can either be a dict, or a json str, or
a key1:value1,key2:value2 formatted string (if compat is True).
If None, an empty dictionary is returned.
:param capabilities: The capabilities value. Can either be a dict, or
a json str, or a key1:value1,key2:value2 formatted
string (if compat is True).
:param compat: Whether to parse the old format key1:value1,key2:value2.
:param skip_malformed: Whether to skip malformed items or raise ValueError.
:returns: A dictionary with the capabilities if found and well formatted,
otherwise an empty dictionary.
:raises: TypeError if the capabilities are of invalid type.
:raises: ValueError on a malformed capability if skip_malformed is False
or on invalid JSON with compat is False.
"""
if capabilities is None:
return {}
elif isinstance(capabilities, str):
try:
return json.loads(capabilities)
except (ValueError, TypeError) as exc:
if compat:
return _parse_old_format(capabilities,
skip_malformed=skip_malformed)
else:
raise ValueError(
_('Invalid JSON capabilities %(value)s: %(error)s')
% {'value': capabilities, 'error': exc})
elif not isinstance(capabilities, dict):
raise TypeError(
_('Invalid capabilities, expected a string or a dict, got %s')
% capabilities)
else:
return capabilities
def combine(capabilities_dict, skip_none=False):
"""Combine capabilities into the old format.
:param capabilities_dict: Capabilities as a mapping.
:param skip_none: If True, skips all items with value of None.
:returns: Capabilities as a string key1:value1,key2:value2.
"""
return ','.join(["%s:%s" % (key, value)
for key, value in capabilities_dict.items()
if not skip_none or value is not None])
def update_and_combine(capabilities, new_values, skip_malformed=False,
skip_none=False):
"""Parses capabilities, updated them with new values and re-combines.
:param capabilities: The capabilities value. Can either be a dict, or
a json str, or a key1:value1,key2:value2 formatted
string (if compat is True).
:param new_values: New values as a dictionary.
:param skip_malformed: Whether to skip malformed items or raise ValueError.
:param skip_none: If True, skips all items with value of None.
:returns: Capabilities in the old format (key1:value1,key2:value2).
:raises: TypeError if the capabilities are of invalid type.
:raises: ValueError on a malformed capability if skip_malformed is False.
"""
if not isinstance(new_values, dict):
raise TypeError(
_("Cannot update capabilities. The new capabilities should be in "
"a dictionary. Provided value is %s") % new_values)
capabilities = parse(capabilities, skip_malformed=skip_malformed)
capabilities.update(new_values)
return combine(capabilities, skip_none=skip_none)