import ipaddress
import re
from pathlib import Path
from urllib.parse import urlsplit, urlunsplit
from django.core.exceptions import ValidationError
from django.utils.deconstruct import deconstructible
from django.utils.functional import SimpleLazyObject
from django.utils.ipv6 import is_valid_ipv6_address
from django.utils.translation import gettext_lazy as _, ngettext_lazy
# These values, if given to validate(), will trigger the self.required check.
EMPTY_VALUES = (None, '', [], (), {})
def _lazy_re_compile(regex, flags=0):
"""Lazily compile a regex with flags."""
def _compile():
# Compile the regex if it was not passed pre-compiled.
if isinstance(regex, str):
return re.compile(regex, flags)
else:
assert not flags, "flags must be empty if regex is passed pre-compiled"
return regex
return SimpleLazyObject(_compile)
[文档]@deconstructible
class RegexValidator:
regex = ''
message = _('Enter a valid value.')
code = 'invalid'
inverse_match = False
flags = 0
def __init__(self, regex=None, message=None, code=None, inverse_match=None, flags=None):
if regex is not None:
self.regex = regex
if message is not None:
self.message = message
if code is not None:
self.code = code
if inverse_match is not None:
self.inverse_match = inverse_match
if flags is not None:
self.flags = flags
if self.flags and not isinstance(self.regex, str):
raise TypeError("If the flags are set, regex must be a regular expression string.")
self.regex = _lazy_re_compile(self.regex, self.flags)
def __call__(self, value):
"""
Validate that the input contains (or does *not* contain, if
inverse_match is True) a match for the regular expression.
"""
regex_matches = self.regex.search(str(value))
invalid_input = regex_matches if self.inverse_match else not regex_matches
if invalid_input:
raise ValidationError(self.message, code=self.code)
def __eq__(self, other):
return (
isinstance(other, RegexValidator) and
self.regex.pattern == other.regex.pattern and
self.regex.flags == other.regex.flags and
(self.message == other.message) and
(self.code == other.code) and
(self.inverse_match == other.inverse_match)
)
[文档]@deconstructible
class URLValidator(RegexValidator):
ul = '\u00a1-\uffff' # unicode letters range (must not be a raw string)
# IP patterns
ipv4_re = r'(?:25[0-5]|2[0-4]\d|[0-1]?\d?\d)(?:\.(?:25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}'
ipv6_re = r'\[[0-9a-f:\.]+\]' # (simple regex, validated later)
# Host patterns
hostname_re = r'[a-z' + ul + r'0-9](?:[a-z' + ul + r'0-9-]{0,61}[a-z' + ul + r'0-9])?'
# Max length for domain name labels is 63 characters per RFC 1034 sec. 3.1
domain_re = r'(?:\.(?!-)[a-z' + ul + r'0-9-]{1,63}(?<!-))*'
tld_re = (
r'\.' # dot
r'(?!-)' # can't start with a dash
r'(?:[a-z' + ul + '-]{2,63}' # domain label
r'|xn--[a-z0-9]{1,59})' # or punycode label
r'(?<!-)' # can't end with a dash
r'\.?' # may have a trailing dot
)
host_re = '(' + hostname_re + domain_re + tld_re + '|localhost)'
regex = _lazy_re_compile(
r'^(?:[a-z0-9\.\-\+]*)://' # scheme is validated separately
r'(?:[^\s:@/]+(?::[^\s:@/]*)?@)?' # user:pass authentication
r'(?:' + ipv4_re + '|' + ipv6_re + '|' + host_re + ')'
r'(?::\d{2,5})?' # port
r'(?:[/?#][^\s]*)?' # resource path
r'\Z', re.IGNORECASE)
message = _('Enter a valid URL.')
schemes = ['http', 'https', 'ftp', 'ftps']
def __init__(self, schemes=None, **kwargs):
super().__init__(**kwargs)
if schemes is not None:
self.schemes = schemes
def __call__(self, value):
# Check first if the scheme is valid
scheme = value.split('://')[0].lower()
if scheme not in self.schemes:
raise ValidationError(self.message, code=self.code)
# Then check full URL
try:
super().__call__(value)
except ValidationError as e:
# Trivial case failed. Try for possible IDN domain
if value:
try:
scheme, netloc, path, query, fragment = urlsplit(value)
except ValueError: # for example, "Invalid IPv6 URL"
raise ValidationError(self.message, code=self.code)
try:
netloc = netloc.encode('idna').decode('ascii') # IDN -> ACE
except UnicodeError: # invalid domain part
raise e
url = urlunsplit((scheme, netloc, path, query, fragment))
super().__call__(url)
else:
raise
else:
# Now verify IPv6 in the netloc part
host_match = re.search(r'^\[(.+)\](?::\d{2,5})?$', urlsplit(value).netloc)
if host_match:
potential_ip = host_match.groups()[0]
try:
validate_ipv6_address(potential_ip)
except ValidationError:
raise ValidationError(self.message, code=self.code)
# The maximum length of a full host name is 253 characters per RFC 1034
# section 3.1. It's defined to be 255 bytes or less, but this includes
# one byte for the length of the name and one byte for the trailing dot
# that's used to indicate absolute names in DNS.
if len(urlsplit(value).netloc) > 253:
raise ValidationError(self.message, code=self.code)
integer_validator = RegexValidator(
_lazy_re_compile(r'^-?\d+\Z'),
message=_('Enter a valid integer.'),
code='invalid',
)
def validate_integer(value):
return integer_validator(value)
[文档]@deconstructible
class EmailValidator:
message = _('Enter a valid email address.')
code = 'invalid'
user_regex = _lazy_re_compile(
r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z]+)*\Z" # dot-atom
r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-\011\013\014\016-\177])*"\Z)', # quoted-string
re.IGNORECASE)
domain_regex = _lazy_re_compile(
# max length for domain name labels is 63 characters per RFC 1034
r'((?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+)(?:[A-Z0-9-]{2,63}(?<!-))\Z',
re.IGNORECASE)
literal_regex = _lazy_re_compile(
# literal form, ipv4 or ipv6 address (SMTP 4.1.3)
r'\[([A-f0-9:\.]+)\]\Z',
re.IGNORECASE)
domain_whitelist = ['localhost']
def __init__(self, message=None, code=None, whitelist=None):
if message is not None:
self.message = message
if code is not None:
self.code = code
if whitelist is not None:
self.domain_whitelist = whitelist
def __call__(self, value):
if not value or '@' not in value:
raise ValidationError(self.message, code=self.code)
user_part, domain_part = value.rsplit('@', 1)
if not self.user_regex.match(user_part):
raise ValidationError(self.message, code=self.code)
if (domain_part not in self.domain_whitelist and
not self.validate_domain_part(domain_part)):
# Try for possible IDN domain-part
try:
domain_part = domain_part.encode('idna').decode('ascii')
except UnicodeError:
pass
else:
if self.validate_domain_part(domain_part):
return
raise ValidationError(self.message, code=self.code)
def validate_domain_part(self, domain_part):
if self.domain_regex.match(domain_part):
return True
literal_match = self.literal_regex.match(domain_part)
if literal_match:
ip_address = literal_match.group(1)
try:
validate_ipv46_address(ip_address)
return True
except ValidationError:
pass
return False
def __eq__(self, other):
return (
isinstance(other, EmailValidator) and
(self.domain_whitelist == other.domain_whitelist) and
(self.message == other.message) and
(self.code == other.code)
)
validate_email = EmailValidator()
slug_re = _lazy_re_compile(r'^[-a-zA-Z0-9_]+\Z')
validate_slug = RegexValidator(
slug_re,
# Translators: "letters" means latin letters: a-z and A-Z.
_("Enter a valid 'slug' consisting of letters, numbers, underscores or hyphens."),
'invalid'
)
slug_unicode_re = _lazy_re_compile(r'^[-\w]+\Z')
validate_unicode_slug = RegexValidator(
slug_unicode_re,
_("Enter a valid 'slug' consisting of Unicode letters, numbers, underscores, or hyphens."),
'invalid'
)
[文档]def validate_ipv4_address(value):
try:
ipaddress.IPv4Address(value)
except ValueError:
raise ValidationError(_('Enter a valid IPv4 address.'), code='invalid')
[文档]def validate_ipv6_address(value):
if not is_valid_ipv6_address(value):
raise ValidationError(_('Enter a valid IPv6 address.'), code='invalid')
[文档]def validate_ipv46_address(value):
try:
validate_ipv4_address(value)
except ValidationError:
try:
validate_ipv6_address(value)
except ValidationError:
raise ValidationError(_('Enter a valid IPv4 or IPv6 address.'), code='invalid')
ip_address_validator_map = {
'both': ([validate_ipv46_address], _('Enter a valid IPv4 or IPv6 address.')),
'ipv4': ([validate_ipv4_address], _('Enter a valid IPv4 address.')),
'ipv6': ([validate_ipv6_address], _('Enter a valid IPv6 address.')),
}
def ip_address_validators(protocol, unpack_ipv4):
"""
Depending on the given parameters, return the appropriate validators for
the GenericIPAddressField.
"""
if protocol != 'both' and unpack_ipv4:
raise ValueError(
"You can only use `unpack_ipv4` if `protocol` is set to 'both'")
try:
return ip_address_validator_map[protocol.lower()]
except KeyError:
raise ValueError("The protocol '%s' is unknown. Supported: %s"
% (protocol, list(ip_address_validator_map)))
[文档]def int_list_validator(sep=',', message=None, code='invalid', allow_negative=False):
regexp = _lazy_re_compile(r'^%(neg)s\d+(?:%(sep)s%(neg)s\d+)*\Z' % {
'neg': '(-)?' if allow_negative else '',
'sep': re.escape(sep),
})
return RegexValidator(regexp, message=message, code=code)
validate_comma_separated_integer_list = int_list_validator(
message=_('Enter only digits separated by commas.'),
)
@deconstructible
class BaseValidator:
message = _('Ensure this value is %(limit_value)s (it is %(show_value)s).')
code = 'limit_value'
def __init__(self, limit_value, message=None):
self.limit_value = limit_value
if message:
self.message = message
def __call__(self, value):
cleaned = self.clean(value)
limit_value = self.limit_value() if callable(self.limit_value) else self.limit_value
params = {'limit_value': limit_value, 'show_value': cleaned, 'value': value}
if self.compare(cleaned, limit_value):
raise ValidationError(self.message, code=self.code, params=params)
def __eq__(self, other):
return (
isinstance(other, self.__class__) and
self.limit_value == other.limit_value and
self.message == other.message and
self.code == other.code
)
def compare(self, a, b):
return a is not b
def clean(self, x):
return x
[文档]@deconstructible
class MaxValueValidator(BaseValidator):
message = _('Ensure this value is less than or equal to %(limit_value)s.')
code = 'max_value'
def compare(self, a, b):
return a > b
[文档]@deconstructible
class MinValueValidator(BaseValidator):
message = _('Ensure this value is greater than or equal to %(limit_value)s.')
code = 'min_value'
def compare(self, a, b):
return a < b
[文档]@deconstructible
class MinLengthValidator(BaseValidator):
message = ngettext_lazy(
'Ensure this value has at least %(limit_value)d character (it has %(show_value)d).',
'Ensure this value has at least %(limit_value)d characters (it has %(show_value)d).',
'limit_value')
code = 'min_length'
def compare(self, a, b):
return a < b
def clean(self, x):
return len(x)
[文档]@deconstructible
class MaxLengthValidator(BaseValidator):
message = ngettext_lazy(
'Ensure this value has at most %(limit_value)d character (it has %(show_value)d).',
'Ensure this value has at most %(limit_value)d characters (it has %(show_value)d).',
'limit_value')
code = 'max_length'
def compare(self, a, b):
return a > b
def clean(self, x):
return len(x)
[文档]@deconstructible
class DecimalValidator:
"""
Validate that the input does not exceed the maximum number of digits
expected, otherwise raise ValidationError.
"""
messages = {
'invalid': _('Enter a number.'),
'max_digits': ngettext_lazy(
'Ensure that there are no more than %(max)s digit in total.',
'Ensure that there are no more than %(max)s digits in total.',
'max'
),
'max_decimal_places': ngettext_lazy(
'Ensure that there are no more than %(max)s decimal place.',
'Ensure that there are no more than %(max)s decimal places.',
'max'
),
'max_whole_digits': ngettext_lazy(
'Ensure that there are no more than %(max)s digit before the decimal point.',
'Ensure that there are no more than %(max)s digits before the decimal point.',
'max'
),
}
def __init__(self, max_digits, decimal_places):
self.max_digits = max_digits
self.decimal_places = decimal_places
def __call__(self, value):
digit_tuple, exponent = value.as_tuple()[1:]
if exponent in {'F', 'n', 'N'}:
raise ValidationError(self.messages['invalid'])
if exponent >= 0:
# A positive exponent adds that many trailing zeros.
digits = len(digit_tuple) + exponent
decimals = 0
else:
# If the absolute value of the negative exponent is larger than the
# number of digits, then it's the same as the number of digits,
# because it'll consume all of the digits in digit_tuple and then
# add abs(exponent) - len(digit_tuple) leading zeros after the
# decimal point.
if abs(exponent) > len(digit_tuple):
digits = decimals = abs(exponent)
else:
digits = len(digit_tuple)
decimals = abs(exponent)
whole_digits = digits - decimals
if self.max_digits is not None and digits > self.max_digits:
raise ValidationError(
self.messages['max_digits'],
code='max_digits',
params={'max': self.max_digits},
)
if self.decimal_places is not None and decimals > self.decimal_places:
raise ValidationError(
self.messages['max_decimal_places'],
code='max_decimal_places',
params={'max': self.decimal_places},
)
if (self.max_digits is not None and self.decimal_places is not None and
whole_digits > (self.max_digits - self.decimal_places)):
raise ValidationError(
self.messages['max_whole_digits'],
code='max_whole_digits',
params={'max': (self.max_digits - self.decimal_places)},
)
def __eq__(self, other):
return (
isinstance(other, self.__class__) and
self.max_digits == other.max_digits and
self.decimal_places == other.decimal_places
)
[文档]@deconstructible
class FileExtensionValidator:
message = _(
"File extension '%(extension)s' is not allowed. "
"Allowed extensions are: '%(allowed_extensions)s'."
)
code = 'invalid_extension'
def __init__(self, allowed_extensions=None, message=None, code=None):
if allowed_extensions is not None:
allowed_extensions = [allowed_extension.lower() for allowed_extension in allowed_extensions]
self.allowed_extensions = allowed_extensions
if message is not None:
self.message = message
if code is not None:
self.code = code
def __call__(self, value):
extension = Path(value.name).suffix[1:].lower()
if self.allowed_extensions is not None and extension not in self.allowed_extensions:
raise ValidationError(
self.message,
code=self.code,
params={
'extension': extension,
'allowed_extensions': ', '.join(self.allowed_extensions)
}
)
def __eq__(self, other):
return (
isinstance(other, self.__class__) and
self.allowed_extensions == other.allowed_extensions and
self.message == other.message and
self.code == other.code
)
def get_available_image_extensions():
try:
from PIL import Image
except ImportError:
return []
else:
Image.init()
return [ext.lower()[1:] for ext in Image.EXTENSION]
[文档]def validate_image_file_extension(value):
return FileExtensionValidator(allowed_extensions=get_available_image_extensions())(value)
[文档]@deconstructible
class ProhibitNullCharactersValidator:
"""Validate that the string doesn't contain the null character."""
message = _('Null characters are not allowed.')
code = 'null_characters_not_allowed'
def __init__(self, message=None, code=None):
if message is not None:
self.message = message
if code is not None:
self.code = code
def __call__(self, value):
if '\x00' in str(value):
raise ValidationError(self.message, code=self.code)
def __eq__(self, other):
return (
isinstance(other, self.__class__) and
self.message == other.message and
self.code == other.code
)
