Source code for bokeh.models.callbacks

#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2023, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
''' Client-side interactivity.

'''

#-----------------------------------------------------------------------------
# Boilerplate
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from __future__ import annotations

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

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# Imports
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# Standard library imports
import pathlib
from typing import TYPE_CHECKING, Any as any

# Bokeh imports
from ..core.has_props import HasProps, abstract
from ..core.properties import (
    Any,
    AnyRef,
    Auto,
    Bool,
    Dict,
    Either,
    Instance,
    Required,
    String,
)
from ..core.property.bases import Init
from ..core.property.singletons import Intrinsic
from ..core.validation import error
from ..core.validation.errors import INVALID_PROPERTY_VALUE, NOT_A_PROPERTY_OF
from ..model import Model

if TYPE_CHECKING:
    from ..core.types import PathLike

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# Globals and constants
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__all__ = (
    'Callback',
    'OpenURL',
    'CustomJS',
    'SetValue',
)

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# General API
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[docs]@abstract class Callback(Model): ''' Base class for interactive callback. ''' # explicit __init__ to support Init signatures def __init__(self, *args, **kwargs) -> None: super().__init__(*args, **kwargs)
[docs]class OpenURL(Callback): ''' Open a URL in a new or current tab or window. ''' # explicit __init__ to support Init signatures def __init__(self, *args, **kwargs) -> None: super().__init__(*args, **kwargs) url = String("http://", help=""" The URL to direct the web browser to. This can be a template string, which will be formatted with data from the data source. """) same_tab = Bool(False, help=""" Open URL in a new (`False`, default) or current (`True`) tab or window. For `same_tab=False`, whether tab or window will be opened is browser dependent. """)
class CustomCode(Callback): """ """ # explicit __init__ to support Init signatures def __init__(self, *args, **kwargs) -> None: super().__init__(*args, **kwargs)
[docs]class CustomJS(CustomCode): ''' Execute a JavaScript function. .. warning:: The explicit purpose of this Bokeh Model is to embed *raw JavaScript code* for a browser to execute. If any part of the code is derived from untrusted user inputs, then you must take appropriate care to sanitize the user input prior to passing to Bokeh. ''' # explicit __init__ to support Init signatures def __init__(self, *args, **kwargs) -> None: super().__init__(*args, **kwargs) args = Dict(String, AnyRef)(default={}, help=""" A mapping of names to Python objects. In particular those can be bokeh's models. These objects are made available to the callback's code snippet as the values of named parameters to the callback. """) code = Required(String)(help=""" A snippet of JavaScript code to execute in the browser. This can be interpreted either as a JavaScript function or a module, depending on the ``module`` property: 1. A JS function. The code is made into the body of a function, and all of of the named objects in ``args`` are available as parameters that the code can use. Additionally, a ``cb_obj`` parameter contains the object that triggered the callback an optional ``cb_data`` parameter that contains any tool-specific data (i.e. mouse coordinates and hovered glyph indices for the ``HoverTool``) and additional document context in ``cb_context`` argument. 2. An ES module. A JavaScript module (ESM) exporting a default function with the following signature: .. code-block: javascript export default function(args, obj, data, context) { // program logic } where ``args`` is a key-value mapping of user-provided parameters, ``obj`` refers to the object that triggered the callback, ``data`` is a key-value mapping of optional parameters provided by the caller, and ``context`` is an additional document context. The additional document context is composed of the following members: * ``index``: The view manager governing all views in the current instance of ``Bokeh``. If only one instance of ``Bokeh`` is loaded, then this is equivalent to using ``Bokeh.index``. This function can be an asynchronous function (``async function () {}`` or ``async () => {}``) if for example external resources are needed, which would require usage of one of the asynchronous Web APIs, for example: .. code-block: javascript const response = await fetch("/assets/data.csv") const data = await response.text() """) module = Either(Auto, Bool, default="auto", help=""" Whether to interpret the code as a JS function or ES module. If set to ``"auto"``, the this will be inferred from the code. """)
[docs] @classmethod def from_file(cls, path: PathLike, **args: any) -> CustomJS: """ Construct a ``CustomJS`` instance from a ``*.js`` or ``*.mjs`` file. For example, if we want to construct a ``CustomJS`` instance from a JavaScript module ``my_module.mjs``, that takes a single argument ``source``, then we would use: .. code-block: python from bokeh.models import ColumnDataSource, CustomJS source = ColumnDataSource(data=dict(x=[1, 2, 3])) CustomJS.from_file("./my_module.mjs", source=source) """ path = pathlib.Path(path) if path.suffix == ".js": module = False elif path.suffix == ".mjs": module = True else: raise RuntimeError(f"expected a *.js or *.mjs file, got {path}") with open(path, encoding="utf-8") as file: code = file.read() return CustomJS(code=code, args=args, module=module)
[docs]class SetValue(Callback): """ Allows to update a property of an object. """ # explicit __init__ to support Init signatures def __init__(self, obj: Init[HasProps] = Intrinsic, attr: Init[str] = Intrinsic, value: Init[any] = Intrinsic, **kwargs) -> None: super().__init__(obj=obj, attr=attr, value=value, **kwargs) obj: HasProps = Required(Instance(HasProps), help=""" Object to set the value on. """) attr: str = Required(String, help=""" The property to modify. """) value = Required(Any, help=""" The value to set. """) @error(NOT_A_PROPERTY_OF) def _check_if_an_attribute_is_a_property_of_a_model(self): if self.obj.lookup(self.attr, raises=False): return None else: return f"{self.attr} is not a property of {self.obj}" @error(INVALID_PROPERTY_VALUE) def _check_if_provided_a_valid_value(self): descriptor = self.obj.lookup(self.attr) if descriptor.property.is_valid(self.value): return None else: return f"{self.value!r} is not a valid value for {self.obj}.{self.attr}"
# TODO: class Show(Callback): target = Required(Either(Instance(DOMNode), Instance(UIElement))) # TODO: class Hide(Callback): ... #----------------------------------------------------------------------------- # Dev API #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Private API #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Code #-----------------------------------------------------------------------------