Source code for ipywidgets.widgets.trait_types

# Copyright (c) Jupyter Development Team.
# Distributed under the terms of the Modified BSD License.

"""
Trait types for html widgets.
"""

import re
import traitlets
import datetime as dt


_color_names = ['aliceblue', 'antiquewhite', 'aqua', 'aquamarine', 'azure', 'beiae', 'bisque', 'black', 'blanchedalmond', 'blue', 'blueviolet', 'brown', 'burlywood', 'cadetblue', 'chartreuse', 'chocolate', 'coral', 'cornflowerblue', 'cornsilk', 'crimson', 'cyan', 'darkblue', 'darkcyan', 'darkgoldenrod', 'darkgray', 'darkgrey', 'darkgreen', 'darkkhaki', 'darkmagenta', 'darkolivegreen', 'darkorange', 'darkorchid', 'darkred', 'darksalmon', 'darkseagreen', 'darkslateblue', 'darkslategray', 'darkslategrey', 'darkturquoise', 'darkviolet', 'deeppink', 'deepskyblue', 'dimgray', 'dimgrey', 'dodgerblue', 'firebrick', 'floralwhite', 'forestgreen', 'fuchsia', 'gainsboro', 'ghostwhite', 'gold', 'goldenrod', 'gray', 'grey', 'green', 'greenyellow', 'honeydew', 'hotpink', 'indianred ', 'indigo ', 'ivory', 'khaki', 'lavender', 'lavenderblush', 'lawngreen', 'lemonchiffon', 'lightblue', 'lightcoral', 'lightcyan', 'lightgoldenrodyellow', 'lightgray', 'lightgrey', 'lightgreen', 'lightpink', 'lightsalmon', 'lightseagreen', 'lightskyblue', 'lightslategray', 'lightslategrey', 'lightsteelblue', 'lightyellow', 'lime', 'limegreen', 'linen', 'magenta', 'maroon', 'mediumaquamarine', 'mediumblue', 'mediumorchid', 'mediumpurple', 'mediumseagreen', 'mediumslateblue', 'mediumspringgreen', 'mediumturquoise', 'mediumvioletred', 'midnightblue', 'mintcream', 'mistyrose', 'moccasin', 'navajowhite', 'navy', 'oldlace', 'olive', 'olivedrab', 'orange', 'orangered', 'orchid', 'palegoldenrod', 'palegreen', 'paleturquoise', 'palevioletred', 'papayawhip', 'peachpuff', 'peru', 'pink', 'plum', 'powderblue', 'purple', 'rebeccapurple', 'red', 'rosybrown', 'royalblue', 'saddlebrown', 'salmon', 'sandybrown', 'seagreen', 'seashell', 'sienna', 'silver', 'skyblue', 'slateblue', 'slategray', 'slategrey', 'snow', 'springgreen', 'steelblue', 'tan', 'teal', 'thistle', 'tomato', 'transparent', 'turquoise', 'violet', 'wheat', 'white', 'whitesmoke', 'yellow', 'yellowgreen']

# Regex colors #fff and #ffffff
_color_hex = r'#[a-fA-F0-9]{3}(?:[a-fA-F0-9]{3})?'
_color_hex_re = re.compile(fr'^{_color_hex}$')
# Regex colors #ffff and #ffffffff (includes alpha value)
_color_hexa = r'#[a-fA-F0-9]{4}(?:[a-fA-F0-9]{4})?'
_color_hexa_re = re.compile(fr'^{_color_hexa}$')

# Helpers (float percent, int percent with optional surrounding whitespace)
_color_frac_percent = r'\s*(\d+(\.\d*)?|\.\d+)?%?\s*'
_color_int_percent = r'\s*\d+%?\s*'

# rgb(), rgba(), hsl() and hsla() format strings
_color_rgb = r'rgb\({ip},{ip},{ip}\)'
_color_rgba = r'rgba\({ip},{ip},{ip},{fp}\)'
_color_hsl = r'hsl\({fp},{fp},{fp}\)'
_color_hsla = r'hsla\({fp},{fp},{fp},{fp}\)'

# Regex colors rgb/rgba/hsl/hsla
_color_rgbhsl = '({})|({})|({})|({})'.format(
    _color_rgb, _color_rgba, _color_hsl, _color_hsla
).format(ip=_color_int_percent, fp=_color_frac_percent)
_color_rgbhsl_re = re.compile(_color_rgbhsl)

# Support for CSS variables.
# For production rules, see: https://drafts.csswg.org/css-syntax-3/#tokenization

_escape = r'\\([0-9a-fA-F]{1-6}\s?|[^0-9a-fA-F\s])'
_non_ascii = r''.join(
    (
        r'\u00B7',
        r'\u00C0-\u00D6',
        r'\u00C0-\u00D6',
        r'\u00D8-\u00F6',
        r'\u00F8-\u037D',
        r'\u037F-\u1FFF',
        r'\u200C',
        r'\u200D',
        r'\u203F',
        r'\u2040',
        r'\u2070-\u218F',
        r'\u2C00-\u2FEF',
        r'\u3001-\uD7FF',
        r'\uF900-\uFDCF',
        r'\uFDF0-\uFFFD',
        r'\u10000'
    )
)

# Custom CSS identifier
_custom_ident = fr'--([a-zA-Z0-9_\-{_non_ascii}]|{_escape})+'

# Matching for CSS variables with valid color fallback declaration values.
#
# A CSS variable consists of a custom identifier starting with '--'.
# The 'var()' function can be used for substituting the custom property into
# the value of another property.
#
# Here we further restrict the fallback values to be valid colors.

_css_color = fr'({"|".join(_color_names)}|({_color_rgbhsl})|({_color_hex})|({_color_hexa}))'
_css_var_fallback_color = fr'var\({_custom_ident}(,\s*({_css_color}\s*)?)?\)'
_color_var_re = re.compile(_css_var_fallback_color)


[docs]class Color(traitlets.Unicode): """A string holding a valid HTML color such as 'blue', '#060482', '#A80'""" info_text = 'a valid HTML color' default_value = traitlets.Undefined def validate(self, obj, value): if value is None and self.allow_none: return value if isinstance(value, str): if (value.lower() in _color_names or _color_hex_re.match(value) or _color_hexa_re.match(value) or _color_rgbhsl_re.match(value) or _color_var_re.match(value)): return value self.error(obj, value)
[docs]class Datetime(traitlets.TraitType): """A trait type holding a Python datetime object""" klass = dt.datetime default_value = dt.datetime(1900, 1, 1)
[docs]class Date(traitlets.TraitType): """A trait type holding a Python date object""" klass = dt.date default_value = dt.date(1900, 1, 1)
[docs]class Time(traitlets.TraitType): """A trait type holding a Python time object""" klass = dt.date default_value = dt.time()
def datetime_to_json(pydt, manager): """Serialize a Python datetime object to json. Instantiating a JavaScript Date object with a string assumes that the string is a UTC string, while instantiating it with constructor arguments assumes that it's in local time: >>> cdate = new Date('2015-05-12') Mon May 11 2015 20:00:00 GMT-0400 (Eastern Daylight Time) >>> cdate = new Date(2015, 4, 12) // Months are 0-based indices in JS Tue May 12 2015 00:00:00 GMT-0400 (Eastern Daylight Time) Attributes of this dictionary are to be passed to the JavaScript Date constructor. """ if pydt is None: return None else: try: utcdt = pydt.astimezone(dt.timezone.utc) except (ValueError, OSError): # If year is outside valid range for conversion, # use it as-is utcdt = pydt return dict( year=utcdt.year, month=utcdt.month - 1, # Months are 0-based indices in JS date=utcdt.day, hours=utcdt.hour, # Hours, Minutes, Seconds and Milliseconds minutes=utcdt.minute, # are plural in JS seconds=utcdt.second, milliseconds=utcdt.microsecond / 1000, ) def datetime_from_json(js, manager): """Deserialize a Python datetime object from json.""" if js is None: return None else: try: return dt.datetime( js["year"], js["month"] + 1, # Months are 1-based in Python js["date"], js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000, ).astimezone() except (ValueError, OSError): # If year is outside valid range for conversion, # return UTC datetime return dt.datetime( js["year"], js["month"] + 1, # Months are 1-based in Python js["date"], js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000, dt.timezone.utc, ) datetime_serialization = { 'from_json': datetime_from_json, 'to_json': datetime_to_json }
[docs]def naive_to_json(pydt, manager): """Serialize a naive Python datetime object to json. Instantiating a JavaScript Date object with a string assumes that the string is a UTC string, while instantiating it with constructor arguments assumes that it's in local time: >>> cdate = new Date('2015-05-12') Mon May 11 2015 20:00:00 GMT-0400 (Eastern Daylight Time) >>> cdate = new Date(2015, 4, 12) // Months are 0-based indices in JS Tue May 12 2015 00:00:00 GMT-0400 (Eastern Daylight Time) Attributes of this dictionary are to be passed to the JavaScript Date constructor. """ if pydt is None: return None else: naivedt = pydt.replace(tzinfo=None) return dict( year=naivedt.year, month=naivedt.month - 1, # Months are 0-based indices in JS date=naivedt.day, hours=naivedt.hour, # Hours, Minutes, Seconds and Milliseconds minutes=naivedt.minute, # are plural in JS seconds=naivedt.second, milliseconds=naivedt.microsecond / 1000, )
[docs]def naive_from_json(js, manager): """Deserialize a naive Python datetime object from json.""" if js is None: return None else: return dt.datetime( js["year"], js["month"] + 1, # Months are 1-based in Python js["date"], js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000, )
naive_serialization = {"from_json": naive_from_json, "to_json": naive_to_json}
[docs]def date_to_json(pydate, manager): """Serialize a Python date object. Attributes of this dictionary are to be passed to the JavaScript Date constructor. """ if pydate is None: return None else: return dict( year=pydate.year, month=pydate.month - 1, # Months are 0-based indices in JS date=pydate.day )
[docs]def date_from_json(js, manager): """Deserialize a Javascript date.""" if js is None: return None else: return dt.date( js['year'], js['month'] + 1, # Months are 1-based in Python js['date'], )
date_serialization = { 'from_json': date_from_json, 'to_json': date_to_json }
[docs]class ByteMemoryView(traitlets.TraitType): """A trait for memory views of bytes.""" default_value = memoryview(b'') info_text = 'a memory view object' def validate(self, obj, value): if isinstance(value, memoryview) and value.format == 'B': return value self.error(obj, value) def default_value_repr(self): return repr(self.default_value.tobytes())
[docs]class CByteMemoryView(ByteMemoryView): """A casting version of the byte memory view trait.""" def validate(self, obj, value): if isinstance(value, memoryview) and value.format == 'B': return value try: mv = memoryview(value) if mv.format != 'B': mv = mv.cast('B') return mv except Exception: self.error(obj, value)
[docs]def time_to_json(pyt, manager): """Serialize a Python time object to json.""" if pyt is None: return None else: return dict( hours=pyt.hour, # Hours, Minutes, Seconds and Milliseconds minutes=pyt.minute, # are plural in JS seconds=pyt.second, milliseconds=pyt.microsecond / 1000, )
[docs]def time_from_json(js, manager): """Deserialize a Python time object from json.""" if js is None: return None else: return dt.time( js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000 )
time_serialization = {"from_json": time_from_json, "to_json": time_to_json}
[docs]def datetime_to_json(pydt, manager): """Serialize a Python datetime object to json. Instantiating a JavaScript Date object with a string assumes that the string is a UTC string, while instantiating it with constructor arguments assumes that it's in local time: >>> cdate = new Date('2015-05-12') Mon May 11 2015 20:00:00 GMT-0400 (Eastern Daylight Time) >>> cdate = new Date(2015, 4, 12) // Months are 0-based indices in JS Tue May 12 2015 00:00:00 GMT-0400 (Eastern Daylight Time) Attributes of this dictionary are to be passed to the JavaScript Date constructor. """ if pydt is None: return None else: try: utcdt = pydt.astimezone(dt.timezone.utc) except (ValueError, OSError): # If year is outside valid range for conversion, # use it as-is utcdt = pydt return dict( year=utcdt.year, month=utcdt.month - 1, # Months are 0-based indices in JS date=utcdt.day, hours=utcdt.hour, # Hours, Minutes, Seconds and Milliseconds minutes=utcdt.minute, # are plural in JS seconds=utcdt.second, milliseconds=utcdt.microsecond / 1000, )
[docs]def datetime_from_json(js, manager): """Deserialize a Python datetime object from json.""" if js is None: return None else: try: return dt.datetime( js["year"], js["month"] + 1, # Months are 1-based in Python js["date"], js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000, dt.timezone.utc, ).astimezone() except (ValueError, OSError): # If year is outside valid range for conversion, # return naive datetime return dt.datetime( js["year"], js["month"] + 1, # Months are 1-based in Python js["date"], js["hours"], js["minutes"], js["seconds"], js["milliseconds"] * 1000, dt.timezone.utc, )
datetime_serialization = {"from_json": datetime_from_json, "to_json": datetime_to_json}
[docs]class InstanceDict(traitlets.Instance): """An instance trait which coerces a dict to an instance. This lets the instance be specified as a dict, which is used to initialize the instance. Also, we default to a trivial instance, even if args and kwargs is not specified.""" def validate(self, obj, value): if isinstance(value, dict): return super().validate(obj, self.klass(**value)) else: return super().validate(obj, value) def make_dynamic_default(self): return self.klass(*(self.default_args or ()), **(self.default_kwargs or {}))
# The regexp is taken # from https://github.com/d3/d3-format/blob/main/src/formatSpecifier.js _number_format_re = re.compile(r'^(?:(.)?([<>=^]))?([+\-\( ])?([$#])?(0)?(\d+)?(,)?(\.\d+)?([a-z%])?$', re.I) # The valid types are taken from # https://github.com/d3/d3-format/blob/main/src/formatTypes.js _number_format_types = { 'e', 'f', 'g', 'r', 's', '%', 'p', 'b', 'o', 'd', 'x', 'X', 'c', '' }
[docs]class NumberFormat(traitlets.Unicode): """A string holding a number format specifier, e.g. '.3f' This traitlet holds a string that can be passed to the `d3-format <https://github.com/d3/d3-format>`_ JavaScript library. The format allowed is similar to the Python format specifier (PEP 3101). """ info_text = 'a valid number format' default_value = traitlets.Undefined def validate(self, obj, value): value = super().validate(obj, value) re_match = _number_format_re.match(value) if re_match is None: self.error(obj, value) else: format_type = re_match.group(9) if format_type is None: return value elif format_type in _number_format_types: return value else: raise traitlets.TraitError( 'The type specifier of a NumberFormat trait must ' 'be one of {}, but a value of \'{}\' was ' 'specified.'.format( list(_number_format_types), format_type) )
[docs]class TypedTuple(traitlets.Container): """A trait for a tuple of any length with type-checked elements.""" klass = tuple _cast_types = (list,)
def bytes_from_json(js, obj): return None if js is None else js.tobytes() bytes_serialization = { 'from_json': bytes_from_json, }