oslo.utils/oslo_utils/strutils.py
ZhijunWei 1803b63823 Update hacking version
Use latest release 1.1.0 and compatible changes w.r.t pep8

Change-Id: Ide3a556918f341de6eafecb36ca431da40a0aed0
Closes-Bug: #1815715
2019-02-13 14:28:34 +08:00

565 lines
20 KiB
Python

# Copyright 2011 OpenStack Foundation.
# 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.
"""
System-level utilities and helper functions.
"""
import collections
import math
import re
import unicodedata
import pyparsing as pp
import six
from six.moves import urllib
from oslo_utils._i18n import _
from oslo_utils import encodeutils
UNIT_PREFIX_EXPONENT = {
'k': 1,
'K': 1,
'Ki': 1,
'M': 2,
'Mi': 2,
'G': 3,
'Gi': 3,
'T': 4,
'Ti': 4,
}
UNIT_SYSTEM_INFO = {
'IEC': (1024, re.compile(r'(^[-+]?\d*\.?\d+)([KMGT]i?)?(b|bit|B)$')),
'SI': (1000, re.compile(r'(^[-+]?\d*\.?\d+)([kMGT])?(b|bit|B)$')),
'mixed': (None, re.compile(r'(^[-+]?\d*\.?\d+)([kKMGT]i?)?(b|bit|B)$')),
}
TRUE_STRINGS = ('1', 't', 'true', 'on', 'y', 'yes')
FALSE_STRINGS = ('0', 'f', 'false', 'off', 'n', 'no')
SLUGIFY_STRIP_RE = re.compile(r"[^\w\s-]")
SLUGIFY_HYPHENATE_RE = re.compile(r"[-\s]+")
# NOTE(flaper87): The following globals are used by `mask_password`
_SANITIZE_KEYS = ['adminPass', 'admin_pass', 'password', 'admin_password',
'auth_token', 'new_pass', 'auth_password', 'secret_uuid',
'secret', 'sys_pswd', 'token', 'configdrive',
'CHAPPASSWORD', 'encrypted_key', 'private_key']
# NOTE(ldbragst): Let's build a list of regex objects using the list of
# _SANITIZE_KEYS we already have. This way, we only have to add the new key
# to the list of _SANITIZE_KEYS and we can generate regular expressions
# for XML and JSON automatically.
_SANITIZE_PATTERNS_2 = {}
_SANITIZE_PATTERNS_1 = {}
# NOTE(amrith): Some regular expressions have only one parameter, some
# have two parameters. Use different lists of patterns here.
_FORMAT_PATTERNS_1 = [r'(%(key)s\s*[=]\s*)[^\s^\'^\"]+']
_FORMAT_PATTERNS_2 = [r'(%(key)s\s*[=]\s*[\"\'])[^\"\']*([\"\'])',
r'(%(key)s\s+[\"\'])[^\"\']*([\"\'])',
r'([-]{2}%(key)s\s+)[^\'^\"^=^\s]+([\s]*)',
r'(<%(key)s>)[^<]*(</%(key)s>)',
r'([\"\']%(key)s[\"\']\s*:\s*[\"\'])[^\"\']*([\"\'])',
r'([\'"][^"\']*%(key)s[\'"]\s*:\s*u?[\'"])[^\"\']*'
'([\'"])',
r'([\'"][^\'"]*%(key)s[\'"]\s*,\s*\'--?[A-z]+\'\s*,\s*u?'
'[\'"])[^\"\']*([\'"])',
r'(%(key)s\s*--?[A-z]+\s*)\S+(\s*)']
# NOTE(dhellmann): Keep a separate list of patterns by key so we only
# need to apply the substitutions for keys we find using a quick "in"
# test.
for key in _SANITIZE_KEYS:
_SANITIZE_PATTERNS_1[key] = []
_SANITIZE_PATTERNS_2[key] = []
for pattern in _FORMAT_PATTERNS_2:
reg_ex = re.compile(pattern % {'key': key}, re.DOTALL)
_SANITIZE_PATTERNS_2[key].append(reg_ex)
for pattern in _FORMAT_PATTERNS_1:
reg_ex = re.compile(pattern % {'key': key}, re.DOTALL)
_SANITIZE_PATTERNS_1[key].append(reg_ex)
def int_from_bool_as_string(subject):
"""Interpret a string as a boolean and return either 1 or 0.
Any string value in:
('True', 'true', 'On', 'on', '1')
is interpreted as a boolean True.
Useful for JSON-decoded stuff and config file parsing
"""
return int(bool_from_string(subject))
def bool_from_string(subject, strict=False, default=False):
"""Interpret a subject as a boolean.
A subject can be a boolean, a string or an integer. Boolean type value
will be returned directly, otherwise the subject will be converted to
a string. A case-insensitive match is performed such that strings
matching 't','true', 'on', 'y', 'yes', or '1' are considered True and,
when `strict=False`, anything else returns the value specified by
'default'.
Useful for JSON-decoded stuff and config file parsing.
If `strict=True`, unrecognized values, including None, will raise a
ValueError which is useful when parsing values passed in from an API call.
Strings yielding False are 'f', 'false', 'off', 'n', 'no', or '0'.
"""
if isinstance(subject, bool):
return subject
if not isinstance(subject, six.string_types):
subject = six.text_type(subject)
lowered = subject.strip().lower()
if lowered in TRUE_STRINGS:
return True
elif lowered in FALSE_STRINGS:
return False
elif strict:
acceptable = ', '.join(
"'%s'" % s for s in sorted(TRUE_STRINGS + FALSE_STRINGS))
msg = _("Unrecognized value '%(val)s', acceptable values are:"
" %(acceptable)s") % {'val': subject,
'acceptable': acceptable}
raise ValueError(msg)
else:
return default
def is_valid_boolstr(value):
"""Check if the provided string is a valid bool string or not.
:param value: value to verify
:type value: string
:returns: true if value is boolean string, false otherwise
.. versionadded:: 3.17
"""
boolstrs = TRUE_STRINGS + FALSE_STRINGS
return str(value).lower() in boolstrs
def string_to_bytes(text, unit_system='IEC', return_int=False):
"""Converts a string into an float representation of bytes.
The units supported for IEC / mixed::
Kb(it), Kib(it), Mb(it), Mib(it), Gb(it), Gib(it), Tb(it), Tib(it)
KB, KiB, MB, MiB, GB, GiB, TB, TiB
The units supported for SI ::
kb(it), Mb(it), Gb(it), Tb(it)
kB, MB, GB, TB
SI units are interpreted as power-of-ten (e.g. 1kb = 1000b). Note
that the SI unit system does not support capital letter 'K'
IEC units are interpreted as power-of-two (e.g. 1MiB = 1MB =
1024b)
Mixed units interpret the "i" to mean IEC, and no "i" to mean SI
(e.g. 1kb = 1000b, 1kib == 1024b). Additionaly, mixed units
interpret 'K' as power-of-ten. This mode is not particuarly
useful for new code, but can help with compatability for parsers
such as GNU parted.
:param text: String input for bytes size conversion.
:param unit_system: Unit system for byte size conversion.
:param return_int: If True, returns integer representation of text
in bytes. (default: decimal)
:returns: Numerical representation of text in bytes.
:raises ValueError: If text has an invalid value.
"""
try:
base, reg_ex = UNIT_SYSTEM_INFO[unit_system]
except KeyError:
msg = _('Invalid unit system: "%s"') % unit_system
raise ValueError(msg)
match = reg_ex.match(text)
if match:
magnitude = float(match.group(1))
unit_prefix = match.group(2)
if match.group(3) in ['b', 'bit']:
magnitude /= 8
# In the mixed matcher, IEC units (with a trailing 'i') are
# interpreted as power-of-two, others as power-of-ten
if unit_system == 'mixed':
if unit_prefix and not unit_prefix.endswith('i'):
# For maximum compatability in mixed mode, we understand
# "K" (which is not strict SI) as "k"
if unit_prefix.startswith == 'K':
unit_prefix = 'k'
base = 1000
else:
base = 1024
else:
msg = _('Invalid string format: %s') % text
raise ValueError(msg)
if not unit_prefix:
res = magnitude
else:
res = magnitude * pow(base, UNIT_PREFIX_EXPONENT[unit_prefix])
if return_int:
return int(math.ceil(res))
return res
def to_slug(value, incoming=None, errors="strict"):
"""Normalize string.
Convert to lowercase, remove non-word characters, and convert spaces
to hyphens.
Inspired by Django's `slugify` filter.
:param value: Text to slugify
:param incoming: Text's current encoding
:param errors: Errors handling policy. See here for valid
values http://docs.python.org/2/library/codecs.html
:returns: slugified unicode representation of `value`
:raises TypeError: If text is not an instance of str
"""
value = encodeutils.safe_decode(value, incoming, errors)
# NOTE(aababilov): no need to use safe_(encode|decode) here:
# encodings are always "ascii", error handling is always "ignore"
# and types are always known (first: unicode; second: str)
value = unicodedata.normalize("NFKD", value).encode(
"ascii", "ignore").decode("ascii")
value = SLUGIFY_STRIP_RE.sub("", value).strip().lower()
return SLUGIFY_HYPHENATE_RE.sub("-", value)
# NOTE(dhellmann): Before submitting a patch to add a new argument to
# this function to allow the caller to pass in "extra" or "additional"
# or "replacement" patterns to be masked out, please note that we have
# discussed that feature many times and always rejected it based on
# the desire to have Oslo functions behave consistently across all
# projects and *especially* to have security features work the same
# way no matter where they are used. If every project adopted its own
# set patterns for secret values, it would be very difficult to audit
# the logging to ensure that everything is properly masked. So, please
# either add your pattern to the module-level variables at the top of
# this file or, even better, pick an existing pattern or key to use in
# your application to ensure that the value is masked by this
# function.
def mask_password(message, secret="***"): # nosec
"""Replace password with *secret* in message.
:param message: The string which includes security information.
:param secret: value with which to replace passwords.
:returns: The unicode value of message with the password fields masked.
For example:
>>> mask_password("'adminPass' : 'aaaaa'")
"'adminPass' : '***'"
>>> mask_password("'admin_pass' : 'aaaaa'")
"'admin_pass' : '***'"
>>> mask_password('"password" : "aaaaa"')
'"password" : "***"'
>>> mask_password("'original_password' : 'aaaaa'")
"'original_password' : '***'"
>>> mask_password("u'original_password' : u'aaaaa'")
"u'original_password' : u'***'"
.. versionadded:: 0.2
.. versionchanged:: 1.1
Replace also ``'auth_token'``, ``'new_pass'`` and ``'auth_password'``
keys.
.. versionchanged:: 1.1.1
Replace also ``'secret_uuid'`` key.
.. versionchanged:: 1.5
Replace also ``'sys_pswd'`` key.
.. versionchanged:: 2.6
Replace also ``'token'`` key.
.. versionchanged:: 2.7
Replace also ``'secret'`` key.
.. versionchanged:: 3.4
Replace also ``'configdrive'`` key.
.. versionchanged:: 3.8
Replace also ``'CHAPPASSWORD'`` key.
"""
try:
message = six.text_type(message)
except UnicodeDecodeError: # nosec
# NOTE(jecarey): Temporary fix to handle cases where message is a
# byte string. A better solution will be provided in Kilo.
pass
substitute1 = r'\g<1>' + secret
substitute2 = r'\g<1>' + secret + r'\g<2>'
# NOTE(ldbragst): Check to see if anything in message contains any key
# specified in _SANITIZE_KEYS, if not then just return the message since
# we don't have to mask any passwords.
for key in _SANITIZE_KEYS:
if key in message:
for pattern in _SANITIZE_PATTERNS_2[key]:
message = re.sub(pattern, substitute2, message)
for pattern in _SANITIZE_PATTERNS_1[key]:
message = re.sub(pattern, substitute1, message)
return message
def mask_dict_password(dictionary, secret="***"): # nosec
"""Replace password with *secret* in a dictionary recursively.
:param dictionary: The dictionary which includes secret information.
:param secret: value with which to replace secret information.
:returns: The dictionary with string substitutions.
A dictionary (which may contain nested dictionaries) contains
information (such as passwords) which should not be revealed, and
this function helps detect and replace those with the 'secret'
provided (or `***` if none is provided).
Substitution is performed in one of three situations:
If the key is something that is considered to be indicative of a
secret, then the corresponding value is replaced with the secret
provided (or `***` if none is provided).
If a value in the dictionary is a string, then it is masked
using the ``mask_password()`` function.
Finally, if a value is a dictionary, this function will
recursively mask that dictionary as well.
For example:
>>> mask_dict_password({'password': 'd81juxmEW_',
>>> 'user': 'admin',
>>> 'home-dir': '/home/admin'},
>>> '???')
{'password': '???', 'user': 'admin', 'home-dir': '/home/admin'}
For example (the value is masked using mask_password())
>>> mask_dict_password({'password': '--password d81juxmEW_',
>>> 'user': 'admin',
>>> 'home-dir': '/home/admin'},
>>> '???')
{'password': '--password ???', 'user': 'admin',
'home-dir': '/home/admin'}
For example (a nested dictionary is masked):
>>> mask_dict_password({"nested": {'password': 'd81juxmEW_',
>>> 'user': 'admin',
>>> 'home': '/home/admin'}},
>>> '???')
{"nested": {'password': '???', 'user': 'admin', 'home': '/home/admin'}}
.. versionadded:: 3.4
"""
if not isinstance(dictionary, collections.Mapping):
raise TypeError("Expected a Mapping, got %s instead."
% type(dictionary))
out = {}
for k, v in dictionary.items():
if isinstance(v, collections.Mapping):
out[k] = mask_dict_password(v, secret=secret)
continue
# NOTE(jlvillal): Check to see if anything in the dictionary 'key'
# contains any key specified in _SANITIZE_KEYS.
k_matched = False
if isinstance(k, six.string_types):
for sani_key in _SANITIZE_KEYS:
if sani_key in k:
out[k] = secret
k_matched = True
break
if not k_matched:
# We did not find a match for the key name in the
# _SANITIZE_KEYS, so we fall through to here
if isinstance(v, six.string_types):
out[k] = mask_password(v, secret=secret)
else:
# Just leave it alone.
out[k] = v
return out
def is_int_like(val):
"""Check if a value looks like an integer with base 10.
:param val: Value to verify
:type val: string
:returns: bool
.. versionadded:: 1.1
"""
try:
return six.text_type(int(val)) == six.text_type(val)
except (TypeError, ValueError):
return False
def check_string_length(value, name=None, min_length=0, max_length=None):
"""Check the length of specified string.
:param value: the value of the string
:param name: the name of the string
:param min_length: the min_length of the string
:param max_length: the max_length of the string
:raises TypeError, ValueError: For any invalid input.
.. versionadded:: 3.7
"""
if name is None:
name = value
if not isinstance(value, six.string_types):
msg = _("%s is not a string or unicode") % name
raise TypeError(msg)
length = len(value)
if length < min_length:
msg = _("%(name)s has %(length)s characters, less than "
"%(min_length)s.") % {'name': name, 'length': length,
'min_length': min_length}
raise ValueError(msg)
if max_length and length > max_length:
msg = _("%(name)s has %(length)s characters, more than "
"%(max_length)s.") % {'name': name, 'length': length,
'max_length': max_length}
raise ValueError(msg)
def validate_integer(value, name, min_value=None, max_value=None):
"""Make sure that value is a valid integer, potentially within range.
:param value: value of the integer
:param name: name of the integer
:param min_value: min_value of the integer
:param max_value: max_value of the integer
:returns: integer
:raises: ValueError if value is an invalid integer
.. versionadded:: 3.33
"""
try:
value = int(str(value))
except (ValueError, UnicodeEncodeError):
msg = _('%(value_name)s must be an integer'
) % {'value_name': name}
raise ValueError(msg)
if min_value is not None and value < min_value:
msg = _('%(value_name)s must be >= %(min_value)d'
) % {'value_name': name, 'min_value': min_value}
raise ValueError(msg)
if max_value is not None and value > max_value:
msg = _('%(value_name)s must be <= %(max_value)d'
) % {'value_name': name, 'max_value': max_value}
raise ValueError(msg)
return value
def split_path(path, minsegs=1, maxsegs=None, rest_with_last=False):
"""Validate and split the given HTTP request path.
**Examples**::
['a'] = _split_path('/a')
['a', None] = _split_path('/a', 1, 2)
['a', 'c'] = _split_path('/a/c', 1, 2)
['a', 'c', 'o/r'] = _split_path('/a/c/o/r', 1, 3, True)
:param path: HTTP Request path to be split
:param minsegs: Minimum number of segments to be extracted
:param maxsegs: Maximum number of segments to be extracted
:param rest_with_last: If True, trailing data will be returned as part
of last segment. If False, and there is
trailing data, raises ValueError.
:returns: list of segments with a length of maxsegs (non-existent
segments will return as None)
:raises: ValueError if given an invalid path
.. versionadded:: 3.11
"""
if not maxsegs:
maxsegs = minsegs
if minsegs > maxsegs:
raise ValueError(_('minsegs > maxsegs: %(min)d > %(max)d)') %
{'min': minsegs, 'max': maxsegs})
if rest_with_last:
segs = path.split('/', maxsegs)
minsegs += 1
maxsegs += 1
count = len(segs)
if (segs[0] or count < minsegs or count > maxsegs or
'' in segs[1:minsegs]):
raise ValueError(_('Invalid path: %s') % urllib.parse.quote(path))
else:
minsegs += 1
maxsegs += 1
segs = path.split('/', maxsegs)
count = len(segs)
if (segs[0] or count < minsegs or count > maxsegs + 1 or
'' in segs[1:minsegs] or
(count == maxsegs + 1 and segs[maxsegs])):
raise ValueError(_('Invalid path: %s') % urllib.parse.quote(path))
segs = segs[1:maxsegs]
segs.extend([None] * (maxsegs - 1 - len(segs)))
return segs
def split_by_commas(value):
"""Split values by commas and quotes according to api-wg
:param value: value to be split
.. versionadded:: 3.17
"""
word = (pp.QuotedString(quoteChar='"', escChar='\\') |
pp.Word(pp.printables, excludeChars='",'))
grammar = pp.stringStart + pp.delimitedList(word) + pp.stringEnd
try:
return list(grammar.parseString(value))
except pp.ParseException:
raise ValueError("Invalid value: %s" % value)