authnzerver.validators module¶

This module contains validation functions taken from the James Bennett’s excellent django-registration package. I’ve modified it a bit so the validators don’t need Django to work. The original docstring and the BSD License for that package are reproduced immediately below.

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Error messages, data and custom validation code used in django-registration’s various user-registration form classes.

authnzerver.validators.get_public_suffix_list(return_set: bool = False, save_to_currproc: bool = False) → Union[list, set][source]¶: Gets the public suffix list and caches it if necessary.

authnzerver.validators.normalize_value(value: str, casefold: bool = True) → str[source]¶

This normalizes a given value and casefolds it.

Assumes that the value has already passed validation.

authnzerver.validators.public_suffix_list(return_set: bool = False) → Union[list, set][source]¶: Retrieves the Internet names public suffix list and loads it into a set.

authnzerver.validators.validate_confusables(value: str)[source]¶: This validates if the value is not a confusable homoglyph.

authnzerver.validators.validate_confusables_email(value: str) → bool[source]¶

Validator which disallows ‘dangerous’ email addresses likely to represent homograph attacks.

An email address is ‘dangerous’ if either the local-part or the domain, considered on their own, are mixed-script and contain one or more characters appearing in the Unicode Visually Confusable Characters file.

authnzerver.validators.validate_email_address(emailaddr: str) → bool[source]¶

This validates an email address using the HTML5 specification, which is good enough for most purposes.

The regex is taken from here:

https://blog.gerv.net/2011/05/html5_email_address_regexp/

And was transformed to Python using the excellent https://regex101.com.

authnzerver.validators.validate_reserved_name(value: str) → bool[source]¶: This validates if the value is not one of the reserved names.

authnzerver.validators.validate_unique_value(value: str, check_list: Sequence[T_co]) → bool[source]¶

This checks if the input value does not already exist in the check_list.

The check_list comes from the DB and should contain user names, etc. that have been already normalized and casefolded.