Source code for bokeh.core.property.string

#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2021, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
""" Provide the Regex property.



"""

#-----------------------------------------------------------------------------
# Boilerplate
#-----------------------------------------------------------------------------
import logging # isort:skip
log = logging.getLogger(__name__)

#-----------------------------------------------------------------------------
# Imports
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# Standard library imports
import base64
import re

# Bokeh imports
from .primitive import String
from .singletons import Undefined

#-----------------------------------------------------------------------------
# Globals and constants
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__all__ = (
    'Regex',
    'Base64String',
)

#-----------------------------------------------------------------------------
# General API
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class Regex(String):
    """ Accept strings that match a given regular expression.

    Args:
        default (string, optional) :
            A default value for attributes created from this property to have.

        help (str or None, optional) :
            A documentation string for this property. It will be automatically
            used by the :ref:`bokeh.sphinxext.bokeh_prop` extension when
            generating Spinx documentation. (default: None)

        serialized (bool, optional) :
            Whether attributes created from this property should be included
            in serialization (default: True)

        readonly (bool, optional) :
            Whether attributes created from this property are read-only.
            (default: False)

    Example:

        .. code-block:: python

            >>> class RegexModel(HasProps):
            ...     prop = Regex("foo[0-9]+bar")
            ...

            >>> m = RegexModel()

            >>> m.prop = "foo123bar"

            >>> m.prop = "foo"      # ValueError !!

            >>> m.prop = [1, 2, 3]  # ValueError !!

    """
    def __init__(self, regex, default=Undefined, help=None):
        self.regex = re.compile(regex)
        super().__init__(default=default, help=help)

    def __str__(self):
        class_name = self.__class__.__name__
        return f"{class_name}({self.regex.pattern!r})"

    def validate(self, value, detail=True):
        super().validate(value, detail)

        if self.regex.match(value):
            return

        msg = "" if not detail else f"expected a string matching {self.regex.pattern!r} pattern, got {value!r}"
        raise ValueError(msg)

class Base64String(String):

    def serialize_value(self, value):
        """ Encode a ascii string using Base64.

        Args:
            value : a string to encode

        Returns:
            string

        """
        if isinstance(value, str):
            value = base64.b64encode(value.encode("utf-8")).decode("utf-8")
        return value

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# Dev API
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#-----------------------------------------------------------------------------
# Private API
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#-----------------------------------------------------------------------------
# Code
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