A validator is a callable that takes a value and raises a\nValidationError if it doesn’t meet some\ncriteria. Validators can be useful for reusing validation logic between\ndifferent types of fields.
For example, here’s a validator that only allows even numbers:
\nfrom django.core.exceptions import ValidationError\nfrom django.utils.translation import gettext_lazy as _\n\n\ndef validate_even(value):\n if value % 2 != 0:\n raise ValidationError(\n _("%(value)s is not an even number"),\n params={"value": value},\n )\nYou can add this to a model field via the field’s validators\nargument:
from django.db import models\n\n\nclass MyModel(models.Model):\n even_field = models.IntegerField(validators=[validate_even])\nBecause values are converted to Python before validators are run, you can even\nuse the same validator with forms:
\nfrom django import forms\n\n\nclass MyForm(forms.Form):\n even_field = forms.IntegerField(validators=[validate_even])\nYou can also use a class with a __call__() method for more complex or\nconfigurable validators. RegexValidator, for example, uses this\ntechnique. If a class-based validator is used in the\nvalidators model field option, you should make\nsure it is serializable by the migration framework by adding deconstruct() and __eq__() methods.
See the form validation for more information on\nhow validators are run in forms, and Validating objects for how they’re run in models. Note that validators will\nnot be run automatically when you save a model, but if you are using a\nModelForm, it will run your validators on any fields\nthat are included in your form. See the\nModelForm documentation for information on\nhow model validation interacts with forms.
The django.core.validators module contains a collection of callable\nvalidators for use with model and form fields. They’re used internally but\nare available for use with your own fields, too. They can be used in addition\nto, or in lieu of custom field.clean() methods.
RegexValidatorLink para este cabeçalho#regex – If not None, overrides regex. Can be a regular\nexpression string or a pre-compiled regular expression.
message – If not None, overrides message.
code – If not None, overrides code.
inverse_match – If not None, overrides inverse_match.
flags – If not None, overrides flags. In that case,\nregex must be a regular expression string, or\nTypeError is raised.
A RegexValidator searches the provided value for a given\nregular expression with re.search(). By default, raises a\nValidationError with message and\ncode if a match is not found. Its behavior can be inverted by\nsetting inverse_match to True, in which case the\nValidationError is raised when a match\nis found.
The regular expression pattern to search for within the provided\nvalue, using re.search(). This may be a string or a\npre-compiled regular expression created with re.compile().\nDefaults to the empty string, which will be found in every possible\nvalue.
The error message used by\nValidationError if validation fails.\nDefaults to "Enter a valid value".
The error code used by ValidationError\nif validation fails. Defaults to "invalid".
The match mode for regex. Defaults to False.
The regex flags used when\ncompiling the regular expression string regex. If regex\nis a pre-compiled regular expression, and flags is overridden,\nTypeError is raised. Defaults to 0.
EmailValidatorLink para este cabeçalho#An EmailValidator ensures that a value looks like an email, and\nraises a ValidationError with\nmessage and code if it doesn’t. Values longer than 320\ncharacters are always considered invalid.
The error message used by\nValidationError if validation fails.\nDefaults to "Enter a valid email address".
The error code used by ValidationError\nif validation fails. Defaults to "invalid".
Allowlist of email domains. By default, a regular expression (the\ndomain_regex attribute) is used to validate whatever appears after\nthe @ sign. However, if that string appears in the allowlist,\nthis validation is bypassed. If not provided, the default allowlist\nis ['localhost']. Other domains that don’t contain a dot won’t pass\nvalidation, so you’d need to add them to the allowlist as\nnecessary.
DomainNameValidatorLink para este cabeçalho#A RegexValidator subclass that ensures a value looks like a domain\nname. Values longer than 255 characters are always considered invalid. IP\naddresses are not accepted as valid domain names.
In addition to the optional arguments of its parent RegexValidator\nclass, DomainNameValidator accepts an extra optional attribute:
Determines whether to accept internationalized domain names, that is,\ndomain names that contain non-ASCII characters. Defaults to True.
URLValidatorLink para este cabeçalho#A RegexValidator subclass that ensures a value looks like a URL,\nand raises an error code of 'invalid' if it doesn’t. Values longer than\nmax_length characters are always considered invalid.
Loopback addresses and reserved IP spaces are considered valid. Literal\nIPv6 addresses (RFC 3986 Section 3.2.2) and Unicode domains are both\nsupported.
\nIn addition to the optional arguments of its parent RegexValidator\nclass, URLValidator accepts an extra optional attribute:
URL/URI scheme list to validate against. If not provided, the default\nlist is ['http', 'https', 'ftp', 'ftps']. As a reference, the IANA\nwebsite provides a full list of valid URI schemes.
The maximum length of values that could be considered valid. Defaults\nto 2048 characters.
\nvalidate_emailLink para este cabeçalho#An EmailValidator instance without any customizations.
validate_domain_nameLink para este cabeçalho#A DomainNameValidator instance without any customizations.
validate_slugLink para este cabeçalho#A RegexValidator instance that ensures a value consists of only\nletters, numbers, underscores or hyphens.
validate_unicode_slugLink para este cabeçalho#A RegexValidator instance that ensures a value consists of only\nUnicode letters, numbers, underscores, or hyphens.
validate_ipv4_addressLink para este cabeçalho#A RegexValidator instance that ensures a value looks like an IPv4\naddress.
validate_ipv6_addressLink para este cabeçalho#Uses django.utils.ipv6 to check the validity of an IPv6 address.
validate_ipv46_addressLink para este cabeçalho#Uses both validate_ipv4_address and validate_ipv6_address to\nensure a value is either a valid IPv4 or IPv6 address.
validate_comma_separated_integer_listLink para este cabeçalho#A RegexValidator instance that ensures a value is a\ncomma-separated list of integers.
int_list_validatorLink para este cabeçalho#Returns a RegexValidator instance that ensures a string consists\nof integers separated by sep. It allows negative integers when\nallow_negative is True.
MaxValueValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'max_value' if value is greater than limit_value, which may be\na callable.
MinValueValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'min_value' if value is less than limit_value, which may be a\ncallable.
MaxLengthValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'max_length' if the length of value is greater than\nlimit_value, which may be a callable.
MinLengthValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'min_length' if the length of value is less than limit_value,\nwhich may be a callable.
DecimalValidatorLink para este cabeçalho#Raises ValidationError with the following\ncodes:
'max_digits' if the number of digits is larger than max_digits.
'max_decimal_places' if the number of decimals is larger than\ndecimal_places.
'max_whole_digits' if the number of whole digits is larger than\nthe difference between max_digits and decimal_places.
FileExtensionValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'invalid_extension' if the extension of value.name (value is\na File) isn’t found in allowed_extensions.\nThe extension is compared case-insensitively with allowed_extensions.
validate_image_file_extensionLink para este cabeçalho#Uses Pillow to ensure that value.name (value is a\nFile) has a valid image extension.
ProhibitNullCharactersValidatorLink para este cabeçalho#Raises a ValidationError if str(value)\ncontains one or more null characters ('\\x00').
The error message used by\nValidationError if validation fails.\nDefaults to "Null characters are not allowed.".
The error code used by ValidationError\nif validation fails. Defaults to "null_characters_not_allowed".
StepValueValidatorLink para este cabeçalho#Raises a ValidationError with a code of\n'step_size' if value is not an integral multiple of\nlimit_value, which can be a float, integer or decimal value or a\ncallable. When offset is set, the validation occurs against\nlimit_value plus offset. For example, for\nStepValueValidator(3, offset=1.4) valid values include 1.4,\n4.4, 7.4, 10.4, and so on.