"""
Defines the baseclasses that make a component render to a bokeh model
and become viewable including:
* Layoutable: Defines parameters concerned with layout and style
* ServableMixin: Mixin class that defines methods to serve object on server
* Renderable: Defines methods to render a component as a bokeh model
* Viewable: Defines methods to view the component in the
notebook, on the server or in static exports
"""
from __future__ import annotations
import asyncio
import logging
import os
import sys
import threading
import traceback
import uuid
from functools import partial
from typing import (
IO, TYPE_CHECKING, Any, Callable, ClassVar, Dict, List, Mapping, Optional,
)
import param # type: ignore
from bokeh.core.serialization import DeserializationError
from bokeh.document import Document
from bokeh.resources import Resources
from jinja2 import Template
from pyviz_comms import Comm # type: ignore
from ._param import Align, Aspect, Margin
from .config import config, panel_extension
from .io import serve
from .io.document import create_doc_if_none_exists, init_doc
from .io.embed import embed_state
from .io.loading import start_loading_spinner, stop_loading_spinner
from .io.model import add_to_doc, patch_cds_msg
from .io.notebook import (
JupyterCommManagerBinary as JupyterCommManager, ipywidget, render_embed,
render_mimebundle, render_model, show_server,
)
from .io.save import save
from .io.state import curdoc_locked, state
from .util import escape, param_reprs
from .util.warnings import deprecated
if TYPE_CHECKING:
from bokeh.model import Model
from bokeh.server.contexts import BokehSessionContext
from bokeh.server.server import Server
from .io.location import Location
[docs]class Layoutable(param.Parameterized):
"""
Layoutable defines shared style and layout related parameters
for all Panel components with a visual representation.
"""
align = Align(default='start', doc="""
Whether the object should be aligned with the start, end or
center of its container. If set as a tuple it will declare
(vertical, horizontal) alignment.""")
aspect_ratio = Aspect(default=None, doc="""
Describes the proportional relationship between component's
width and height. This works if any of component's dimensions
are flexible in size. If set to a number, ``width / height =
aspect_ratio`` relationship will be maintained. Otherwise, if
set to ``"auto"``, component's preferred width and height will
be used to determine the aspect (if not set, no aspect will be
preserved).""")
background = param.Parameter(default=None, doc="""
Background color of the component.""")
css_classes = param.List(default=[], doc="""
CSS classes to apply to the layout.""")
design = param.ObjectSelector(default=None, objects=[], doc="""
The design system to use to style components.""")
height = param.Integer(default=None, bounds=(0, None), doc="""
The height of the component (in pixels). This can be either
fixed or preferred height, depending on height sizing policy.""")
min_width = param.Integer(default=None, bounds=(0, None), doc="""
Minimal width of the component (in pixels) if width is adjustable.""")
min_height = param.Integer(default=None, bounds=(0, None), doc="""
Minimal height of the component (in pixels) if height is adjustable.""")
max_width = param.Integer(default=None, bounds=(0, None), doc="""
Minimal width of the component (in pixels) if width is adjustable.""")
max_height = param.Integer(default=None, bounds=(0, None), doc="""
Minimal height of the component (in pixels) if height is adjustable.""")
margin = Margin(default=0, doc="""
Allows to create additional space around the component. May
be specified as a two-tuple of the form (vertical, horizontal)
or a four-tuple (top, right, bottom, left).""")
styles = param.Dict(default={}, doc="""
Dictionary of CSS rules to apply to DOM node wrapping the
component.""")
stylesheets = param.List(default=[], doc="""
List of stylesheets defined as URLs pointing to .css files
or raw CSS defined as a string.""")
tags = param.List(default=[], doc="""
List of arbitrary tags to add to the component.
Can be useful for templating or for storing metadata on
the model.""")
width = param.Integer(default=None, bounds=(0, None), doc="""
The width of the component (in pixels). This can be either
fixed or preferred width, depending on width sizing policy.""")
width_policy = param.ObjectSelector(
default="auto", objects=['auto', 'fixed', 'fit', 'min', 'max'], doc="""
Describes how the component should maintain its width.
``"auto"``
Use component's preferred sizing policy.
``"fixed"``
Use exactly ``width`` pixels. Component will overflow if
it can't fit in the available horizontal space.
``"fit"``
Use component's preferred width (if set) and allow it to
fit into the available horizontal space within the minimum
and maximum width bounds (if set). Component's width
neither will be aggressively minimized nor maximized.
``"min"``
Use as little horizontal space as possible, not less than
the minimum width (if set). The starting point is the
preferred width (if set). The width of the component may
shrink or grow depending on the parent layout, aspect
management and other factors.
``"max"``
Use as much horizontal space as possible, not more than
the maximum width (if set). The starting point is the
preferred width (if set). The width of the component may
shrink or grow depending on the parent layout, aspect
management and other factors.
""")
height_policy = param.ObjectSelector(
default="auto", objects=['auto', 'fixed', 'fit', 'min', 'max'], doc="""
Describes how the component should maintain its height.
``"auto"``
Use component's preferred sizing policy.
``"fixed"``
Use exactly ``height`` pixels. Component will overflow if
it can't fit in the available vertical space.
``"fit"``
Use component's preferred height (if set) and allow to fit
into the available vertical space within the minimum and
maximum height bounds (if set). Component's height neither
will be aggressively minimized nor maximized.
``"min"``
Use as little vertical space as possible, not less than
the minimum height (if set). The starting point is the
preferred height (if set). The height of the component may
shrink or grow depending on the parent layout, aspect
management and other factors.
``"max"``
Use as much vertical space as possible, not more than the
maximum height (if set). The starting point is the
preferred height (if set). The height of the component may
shrink or grow depending on the parent layout, aspect
management and other factors.
""")
sizing_mode = param.ObjectSelector(default=None, objects=[
'fixed', 'stretch_width', 'stretch_height', 'stretch_both',
'scale_width', 'scale_height', 'scale_both', None], doc="""
How the component should size itself.
This is a high-level setting for maintaining width and height
of the component. To gain more fine grained control over
sizing, use ``width_policy``, ``height_policy`` and
``aspect_ratio`` instead (those take precedence over
``sizing_mode``).
``"fixed"``
Component is not responsive. It will retain its original
width and height regardless of any subsequent browser
window resize events.
``"stretch_width"``
Component will responsively resize to stretch to the
available width, without maintaining any aspect ratio. The
height of the component depends on the type of the
component and may be fixed or fit to component's contents.
``"stretch_height"``
Component will responsively resize to stretch to the
available height, without maintaining any aspect
ratio. The width of the component depends on the type of
the component and may be fixed or fit to component's
contents.
``"stretch_both"``
Component is completely responsive, independently in width
and height, and will occupy all the available horizontal
and vertical space, even if this changes the aspect ratio
of the component.
``"scale_width"``
Component will responsively resize to stretch to the
available width, while maintaining the original or
provided aspect ratio.
``"scale_height"``
Component will responsively resize to stretch to the
available height, while maintaining the original or
provided aspect ratio.
``"scale_both"``
Component will responsively resize to both the available
width and height, while maintaining the original or
provided aspect ratio.
""")
visible = param.Boolean(default=True, doc="""
Whether the component is visible. Setting visible to false will
hide the component entirely.""")
__abstract = True
def __init__(self, **params):
sizing_mode = params.get('sizing_mode')
if (sizing_mode in ('stretch_width', 'scale_width', 'stretch_both', 'scale_both') and
params.get('width') is not None):
error = (
f"Providing a width-responsive sizing_mode ({params['sizing_mode']!r}) "
"and a fixed width is not supported. Converting fixed width to min_width. "
"If you intended the component to be fully width-responsive remove the height"
"setting, otherwise change it to min_height."
)
if config.layout_compatibility == 'warn':
error += ' To error on the incorrect specification disable the config.layout_compatibility option.'
self.param.warning(error)
else:
raise ValueError(error)
params['min_width'] = params.pop('width')
if (sizing_mode in ('stretch_height', 'scale_height', 'stretch_both', 'scale_both') and
params.get('height') is not None):
error = (
f"Providing a height-responsive sizing_mode ({params['sizing_mode']!r}) "
"and a fixed height is not supported. Converting fixed height to min_height. "
"If you intended the component to be fully height-responsive remove the height "
"setting, otherwise change it to min_height."
)
if config.layout_compatibility == 'warn':
error += ' To error on the incorrect specification disable the config.layout_compatibility option.'
self.param.warning(error)
else:
raise ValueError(error)
params['min_height'] = params.pop('height')
if (params.get('width') is not None and
params.get('height') is not None and
params.get('width_policy') is None and
params.get('height_policy') is None and
'sizing_mode' not in params):
params['sizing_mode'] = 'fixed'
elif (not (self.param.sizing_mode.constant or self.param.sizing_mode.readonly) and
type(self).sizing_mode is None and 'sizing_mode' not in params):
if config.sizing_mode == 'stretch_both':
if params.get('height') is not None:
params['sizing_mode'] = 'stretch_width'
elif params.get('width') is not None:
params['sizing_mode'] = 'stretch_height'
else:
params['sizing_mode'] = config.sizing_mode
elif config.sizing_mode == 'stretch_width' and 'width' not in params:
params['sizing_mode'] = config.sizing_mode
elif config.sizing_mode == 'stretch_height' and 'height' not in params:
params['sizing_mode'] = config.sizing_mode
if 'design' not in params and self.param.design.default is None:
params['design'] = config.design
super().__init__(**params)
class ServableMixin:
"""
Mixin to define methods shared by objects which can served.
"""
def _modify_doc(
self, server_id: str, title: str, doc: Document, location: Optional['Location']
) -> Document:
"""
Callback to handle FunctionHandler document creation.
"""
if server_id:
state._servers[server_id][2].append(doc)
return self.server_doc(doc, title, location) # type: ignore
def _add_location(
self, doc: Document, location: Optional['Location' | bool],
root: Optional['Model'] = None
) -> 'Location':
from .io.location import Location
if isinstance(location, Location):
loc = location
elif doc in state._locations:
loc = state._locations[doc]
else:
loc = Location()
state._locations[doc] = loc
if root is None:
loc_model = loc.get_root(doc)
else:
loc_model = loc._get_model(doc, root)
loc_model.name = 'location'
doc.on_session_destroyed(loc._server_destroy) # type: ignore
doc.add_root(loc_model)
return loc
#----------------------------------------------------------------
# Public API
#----------------------------------------------------------------
def servable(
self, title: Optional[str] = None, location: bool | 'Location' = True,
area: str = 'main', target: Optional[str] = None
) -> 'ServableMixin':
"""
Serves the object or adds it to the configured
pn.state.template if in a `panel serve` context, writes to the
DOM if in a pyodide context and returns the Panel object to
allow it to display itself in a notebook context.
Arguments
---------
title : str
A string title to give the Document (if served as an app)
location : boolean or panel.io.location.Location
Whether to create a Location component to observe and
set the URL location.
area: str (deprecated)
The area of a template to add the component too. Only has an
effect if pn.config.template has been set.
target: str
Target area to write to. If a template has been configured
on pn.config.template this refers to the target area in the
template while in pyodide this refers to the ID of the DOM
node to write to.
Returns
-------
The Panel object itself
"""
if curdoc_locked().session_context:
logger = logging.getLogger('bokeh')
for handler in logger.handlers:
if isinstance(handler, logging.StreamHandler):
handler.setLevel(logging.WARN)
if config.template:
area = target or area or 'main'
template = state.template
assert template is not None
if template.title == template.param.title.default and title:
template.title = title
if area == 'main':
template.main.append(self)
elif area == 'sidebar':
template.sidebar.append(self)
elif area == 'modal':
template.modal.append(self)
elif area == 'header':
template.header.append(self)
else:
self.server_doc(title=title, location=location) # type: ignore
elif state._is_pyodide and 'pyodide_kernel' not in sys.modules:
from .io.pyodide import _IN_WORKER, _get_pyscript_target, write
if _IN_WORKER:
return self
try:
target = target or _get_pyscript_target()
except Exception:
target = None
if target is not None:
asyncio.create_task(write(target, self))
return self
def show(
self, title: Optional[str] = None, port: int = 0, address: Optional[str] = None,
websocket_origin: Optional[str] = None, threaded: bool = False, verbose: bool = True,
open: bool = True, location: bool | 'Location' = True, **kwargs
) -> threading.Thread | 'Server':
"""
Starts a Bokeh server and displays the Viewable in a new tab.
Arguments
---------
title : str | None
A string title to give the Document (if served as an app)
port: int (optional, default=0)
Allows specifying a specific port
address : str
The address the server should listen on for HTTP requests.
websocket_origin: str or list(str) (optional)
A list of hosts that can connect to the websocket.
This is typically required when embedding a server app in
an external web site.
If None, "localhost" is used.
threaded: boolean (optional, default=False)
Whether to launch the Server on a separate thread, allowing
interactive use.
verbose: boolean (optional, default=True)
Whether to print the address and port
open : boolean (optional, default=True)
Whether to open the server in a new browser tab
location : boolean or panel.io.location.Location
Whether to create a Location component to observe and
set the URL location.
Returns
-------
server: bokeh.server.Server or threading.Thread
Returns the Bokeh server instance or the thread the server
was launched on (if threaded=True)
"""
return serve(
self, port=port, address=address, websocket_origin=websocket_origin,
show=open, start=True, title=title, verbose=verbose,
location=location, threaded=threaded, **kwargs
)
class MimeRenderMixin:
"""
Mixin class to allow rendering and syncing objects in notebook
contexts.
"""
def _on_msg(self, ref: str, manager, msg) -> None:
"""
Handles Protocol messages arriving from the client comm.
"""
root, doc, comm = state._views[ref][1:]
patch_cds_msg(root, msg)
held = doc.callbacks.hold_value
patch = manager.assemble(msg)
doc.hold()
try:
patch.apply_to_document(doc, comm.id if comm else None)
except DeserializationError:
self.param.warning(
"Comm received message that could not be deserialized."
)
finally:
doc.unhold()
if held:
doc.hold(held)
def _on_error(self, ref: str, error: Exception) -> None:
if ref not in state._handles or config.console_output in [None, 'disable']:
return
handle, accumulator = state._handles[ref]
formatted = '\n<pre>'+escape(traceback.format_exc())+'</pre>\n'
if config.console_output == 'accumulate':
accumulator.append(formatted)
elif config.console_output == 'replace':
accumulator[:] = [formatted]
if accumulator:
handle.update({'text/html': '\n'.join(accumulator)}, raw=True)
def _on_stdout(self, ref: str, stdout: Any) -> None:
if ref not in state._handles or config.console_output is [None, 'disable']:
return
handle, accumulator = state._handles[ref]
formatted = ["%s</br>" % o for o in stdout]
if config.console_output == 'accumulate':
accumulator.extend(formatted)
elif config.console_output == 'replace':
accumulator[:] = formatted
if accumulator:
handle.update({'text/html': '\n'.join(accumulator)}, raw=True)
def _render_mimebundle(self, model: Model, doc: Document, comm: Comm, location: Location | None = None):
from .models.comm_manager import CommManager
ref = model.ref['id']
manager = CommManager(comm_id=comm.id, plot_id=ref)
client_comm = state._comm_manager.get_client_comm(
on_msg=partial(self._on_msg, ref, manager),
on_error=partial(self._on_error, ref),
on_stdout=partial(self._on_stdout, ref)
)
self._comms[ref] = (comm, client_comm)
manager.client_comm_id = client_comm.id
return render_mimebundle(model, doc, comm, manager, location)
class Renderable(param.Parameterized, MimeRenderMixin):
"""
Baseclass for objects which can be rendered to a Bokeh model.
It therefore declare APIs for initializing the models from
parameter values.
"""
__abstract = True
def __init__(self, **params):
self._internal_callbacks = []
self._documents = {}
self._models = {}
self._comms = {}
self._kernels = {}
super().__init__(**params)
self._found_links = set()
self._logger = logging.getLogger(f'{__name__}.{type(self).__name__}')
def _log(self, msg: str, *args, level: str = 'debug') -> None:
getattr(self._logger, level)(f'Session %s {msg}', id(state.curdoc), *args)
def _get_model(
self, doc: Document, root: Optional['Model'] = None,
parent: Optional['Model'] = None, comm: Optional[Comm] = None
) -> 'Model':
"""
Converts the objects being wrapped by the viewable into a
bokeh model that can be composed in a bokeh layout.
Arguments
----------
doc: bokeh.Document
Bokeh document the bokeh model will be attached to.
root: bokeh.Model
The root layout the viewable will become part of.
parent: bokeh.Model
The parent layout the viewable will become part of.
comm: pyviz_comms.Comm
Optional pyviz_comms when working in notebook
Returns
-------
model: bokeh.Model
"""
raise NotImplementedError
def _cleanup(self, root: Model | None = None) -> None:
"""
Clean up method which is called when a Viewable is destroyed.
Arguments
---------
root: bokeh.model.Model
Bokeh model for the view being cleaned up
"""
if root is None:
return
ref = root.ref['id']
if ref in state._handles:
del state._handles[ref]
def _preprocess(self, root: 'Model', changed=None, old_models=None) -> None:
"""
Applies preprocessing hooks to the root model.
Some preprocessors have to always iterate over the entire
model tree but others only have to update newly added models.
To support the optimized case we optionally provide the
Panel object that was changed and any old, unchanged models
so they can be skipped (see https://github.com/holoviz/panel/pull/4989)
"""
changed = self if changed is None else changed
hooks = self._preprocessing_hooks+self._hooks
for hook in hooks:
try:
hook(self, root, changed, old_models)
except TypeError:
hook(self, root)
def _render_model(self, doc: Optional[Document] = None, comm: Optional[Comm] = None) -> 'Model':
if doc is None:
doc = Document()
if comm is None:
comm = state._comm_manager.get_server_comm()
model = self.get_root(doc, comm)
if config.embed:
embed_state(self, model, doc,
json=config.embed_json,
json_prefix=config.embed_json_prefix,
save_path=config.embed_save_path,
load_path=config.embed_load_path,
progress=False)
else:
add_to_doc(model, doc)
return model
def _init_params(self) -> Mapping[str, Any]:
return {k: v for k, v in self.param.values().items() if v is not None}
def _server_destroy(self, session_context: 'BokehSessionContext') -> None:
"""
Server lifecycle hook triggered when session is destroyed.
"""
doc = session_context._document
if doc not in self._documents:
return
root = self._documents[doc]
ref = root.ref['id']
self._cleanup(root)
del self._documents[doc]
if ref in state._views:
del state._views[ref]
def __repr__(self, depth: int = 0) -> str:
return '{cls}({params})'.format(cls=type(self).__name__,
params=', '.join(param_reprs(self)))
def get_root(
self, doc: Optional[Document] = None, comm: Optional[Comm] = None,
preprocess: bool = True
) -> Model:
"""
Returns the root model and applies pre-processing hooks
Arguments
---------
doc: bokeh.Document
Bokeh document the bokeh model will be attached to.
comm: pyviz_comms.Comm
Optional pyviz_comms when working in notebook
preprocess: boolean (default=True)
Whether to run preprocessing hooks
Returns
-------
Returns the bokeh model corresponding to this panel object
"""
doc = create_doc_if_none_exists(doc)
if self._design and (comm or (state._is_pyodide and not doc.session_context)):
wrapper = self._design._wrapper(self)
if wrapper is self:
root = self._get_model(doc, comm=comm)
if preprocess:
self._preprocess(root)
else:
root = wrapper.get_root(doc, comm, preprocess)
root_view = wrapper
else:
root = self._get_model(doc, comm=comm)
root_view = self
if preprocess:
self._preprocess(root)
ref = root.ref['id']
state._views[ref] = (root_view, root, doc, comm)
return root
[docs]class Viewable(Renderable, Layoutable, ServableMixin):
"""
Viewable is the baseclass all visual components in the panel
library are built on. It defines the interface for declaring any
object that displays itself by transforming the object(s) being
wrapped into models that can be served using bokeh's layout
engine. The class also defines various methods that allow Viewable
objects to be displayed in the notebook and on bokeh server.
"""
loading = param.Boolean(doc="""
Whether or not the Viewable is loading. If True a loading spinner
is shown on top of the Viewable.""")
_preprocessing_hooks: ClassVar[List[Callable[['Viewable', 'Model'], None]]] = []
def __init__(self, **params):
hooks = params.pop('hooks', [])
super().__init__(**params)
self._hooks = hooks
self._update_loading()
self._update_background()
self._update_design()
self._internal_callbacks.extend([
self.param.watch(self._update_background, 'background'),
self.param.watch(self._update_design, 'design'),
self.param.watch(self._update_loading, 'loading')
])
def _update_design(self, *_):
from .theme import Design
from .theme.native import Native
if isinstance(self.design, Design):
self._design = self.design
elif self.design:
self._design = self.design(theme=config.theme)
else:
self._design = Native(theme=config.theme)
def _update_loading(self, *_) -> None:
if self.loading:
start_loading_spinner(self)
else:
stop_loading_spinner(self)
def _update_background(self, *_) -> None:
if self.background == self.styles.get("background", None) or self.background is None:
return
# Warning
prev = f'{type(self).name}(..., background={self.background!r})'
new = f"{type(self).name}(..., styles={{'background': {self.background!r}}})"
deprecated("1.1", prev, new)
self.styles = dict(self.styles, background=self.background)
def _render_model(self, doc: Optional[Document] = None, comm: Optional[Comm] = None) -> 'Model':
if doc is None:
doc = Document()
if comm is None:
comm = state._comm_manager.get_server_comm()
model = self.get_root(doc, comm)
if self._design and self._design.theme.bokeh_theme:
doc.theme = self._design.theme.bokeh_theme
if config.embed:
embed_state(self, model, doc,
json=config.embed_json,
json_prefix=config.embed_json_prefix,
save_path=config.embed_save_path,
load_path=config.embed_load_path,
progress=False)
else:
add_to_doc(model, doc)
return model
def _repr_mimebundle_(self, include=None, exclude=None):
if state._is_pyodide:
from .io.pyodide import (
_IN_WORKER, _get_pyscript_target, render_script,
)
# If in pyodide and not in a worker we are probably in
# PyScript otherwise we are probabably in JupyterLite
if not _IN_WORKER:
target = _get_pyscript_target()
return {'text/html': render_script(self, target)}, {}
loaded = panel_extension._loaded
if not loaded and 'holoviews' in sys.modules:
import holoviews as hv # type: ignore
loaded = hv.extension._loaded
if config.comms in ('vscode', 'ipywidgets'):
widget = ipywidget(self)
if hasattr(widget, '_repr_mimebundle_'):
return widget._repr_mimebundle_(include=include, exclude=exclude), {}
plaintext = repr(widget)
if len(plaintext) > 110:
plaintext = plaintext[:110] + '…'
data = {
'text/plain': plaintext,
}
if widget._view_name is not None:
data['application/vnd.jupyter.widget-view+json'] = {
'version_major': 2,
'version_minor': 0,
'model_id': widget._model_id
}
if config.comms == 'vscode':
from IPython.display import display # type: ignore
display(data, raw=True)
return {'text/html': '<div style="display: none"></div>'}, {}
return data, {}
if not loaded:
self.param.warning('Displaying Panel objects in the notebook '
'requires the panel extension to be loaded. '
'Ensure you run pn.extension() before '
'displaying objects in the notebook.')
return None
if config.comms == 'colab':
from .io.notebook import load_notebook
load_notebook(config.inline)
try:
from IPython import get_ipython # type: ignore
assert get_ipython().kernel is not None
state._comm_manager = JupyterCommManager
except Exception:
pass
if not state._views:
# Initialize the global Location
from .io.location import Location
state._location = location = Location()
else:
location = None
doc = Document()
comm = state._comm_manager.get_server_comm()
model = self._render_model(doc, comm)
if config.embed:
return render_model(model)
bundle, meta = self._render_mimebundle(model, doc, comm, location)
if config.console_output != 'disable' and not state._is_pyodide:
from IPython.display import display
ref = model.ref['id']
handle = display(display_id=uuid.uuid4().hex)
state._handles[ref] = (handle, [])
return bundle, meta
def __str__(self) -> str:
return self.__repr__()
#----------------------------------------------------------------
# Public API
#----------------------------------------------------------------
[docs] def clone(self, **params) -> 'Viewable':
"""
Makes a copy of the object sharing the same parameters.
Arguments
---------
params: Keyword arguments override the parameters on the clone.
Returns
-------
Cloned Viewable object
"""
inherited = {
p: v for p, v in self.param.values().items()
if not self.param[p].readonly and v is not self.param[p].default
and not (v is None and not self.param[p].allow_None)
}
return type(self)(**dict(inherited, **params))
[docs] def pprint(self) -> None:
"""
Prints a compositional repr of the class.
"""
deprecated('1.1', f'{type(self).__name__}.pprint', 'print')
print(self)
[docs] def select(
self, selector: Optional[type | Callable[['Viewable'], bool]] = None
) -> List['Viewable']:
"""
Iterates over the Viewable and any potential children in the
applying the Selector.
Arguments
---------
selector: type or callable or None
The selector allows selecting a subset of Viewables by
declaring a type or callable function to filter by.
Returns
-------
viewables: list(Viewable)
"""
if (selector is None or
(isinstance(selector, type) and isinstance(self, selector)) or
(callable(selector) and not isinstance(selector, type) and selector(self))):
return [self]
else:
return []
[docs] def app(self, notebook_url: str = "localhost:8888", port: int = 0) -> 'Server':
"""
Displays a bokeh server app inline in the notebook.
Arguments
---------
notebook_url: str
URL to the notebook server
port: int (optional, default=0)
Allows specifying a specific port
"""
deprecated('1.1', f'{type(self).__name__}.app', 'panel.io.notebook.show_server')
return show_server(self, notebook_url, port)
[docs] def embed(
self, max_states: int = 1000, max_opts: int = 3, json: bool = False,
json_prefix: str = '', save_path: str = './', load_path: Optional[str] = None,
progress: bool = False, states={}
) -> None:
"""
Renders a static version of a panel in a notebook by evaluating
the set of states defined by the widgets in the model. Note
this will only work well for simple apps with a relatively
small state space.
Arguments
---------
max_states: int
The maximum number of states to embed
max_opts: int
The maximum number of states for a single widget
json: boolean (default=True)
Whether to export the data to json files
json_prefix: str (default='')
Prefix for JSON filename
save_path: str (default='./')
The path to save json files to
load_path: str (default=None)
The path or URL the json files will be loaded from.
progress: boolean (default=False)
Whether to report progress
states: dict (default={})
A dictionary specifying the widget values to embed for each widget
"""
return render_embed(
self, max_states, max_opts, json, json_prefix, save_path,
load_path, progress, states
)
[docs] def save(
self, filename: str | os.PathLike | IO, title: Optional[str] = None,
resources: Resources | None = None, template: str | Template | None = None,
template_variables: Dict[str, Any] = {}, embed: bool = False,
max_states: int = 1000, max_opts: int = 3, embed_json: bool = False,
json_prefix: str='', save_path: str='./', load_path: Optional[str] = None,
progress: bool = True, embed_states: Dict[Any, Any] = {},
as_png: bool | None = None, **kwargs
) -> None:
"""
Saves Panel objects to file.
Arguments
---------
filename: str or file-like object
Filename to save the plot to
title: string
Optional title for the plot
resources: bokeh resources
One of the valid bokeh.resources (e.g. CDN or INLINE)
template:
passed to underlying io.save
template_variables:
passed to underlying io.save
embed: bool
Whether the state space should be embedded in the saved file.
max_states: int
The maximum number of states to embed
max_opts: int
The maximum number of states for a single widget
embed_json: boolean (default=True)
Whether to export the data to json files
json_prefix: str (default='')
Prefix for the auto-generated json directory
save_path: str (default='./')
The path to save json files to
load_path: str (default=None)
The path or URL the json files will be loaded from.
progress: boolean (default=True)
Whether to report progress
embed_states: dict (default={})
A dictionary specifying the widget values to embed for each widget
as_png: boolean (default=None)
To save as a .png. If None save_png will be true if filename is
string and ends with png.
"""
return save(
self, filename, title, resources, template,
template_variables, embed, max_states, max_opts,
embed_json, json_prefix, save_path, load_path, progress,
embed_states, as_png, **kwargs
)
[docs] def server_doc(
self, doc: Optional[Document] = None, title: Optional[str] = None,
location: bool | 'Location' = True
) -> Document:
"""
Returns a serveable bokeh Document with the panel attached
Arguments
---------
doc : bokeh.Document (optional)
The bokeh Document to attach the panel to as a root,
defaults to bokeh.io.curdoc()
title : str
A string title to give the Document
location : boolean or panel.io.location.Location
Whether to create a Location component to observe and
set the URL location.
Returns
-------
doc : bokeh.Document
The bokeh document the panel was attached to
"""
doc = init_doc(doc)
if title or doc.title == 'Bokeh Application':
title = title or 'Panel Application'
doc.title = title
if self._design:
wrapper = self._design._wrapper(self)
if wrapper is self:
model = self.get_root(doc)
else:
model = wrapper.get_root(doc)
ref = model.ref['id']
state._views[ref] = (wrapper, model, doc, None)
else:
model = self.get_root(doc)
doc.on_session_destroyed(state._destroy_session)
doc.on_session_destroyed(self._server_destroy) # type: ignore
self._documents[doc] = model
add_to_doc(model, doc)
if location:
self._add_location(doc, location, model)
if config.notifications and doc is state.curdoc:
notification_model = state.notifications._get_model(doc, model)
notification_model.name = 'notifications'
doc.add_root(notification_model)
if config.browser_info and doc is state.curdoc:
browser_model = state.browser_info._get_model(doc, model)
browser_model.name = 'browser_info'
doc.add_root(browser_model)
return doc
[docs]class Viewer(param.Parameterized):
"""
A baseclass for custom components that behave like a Panel object.
By implementing __panel__ method an instance of this class will
behave like the returned Panel component when placed in a layout,
render itself in a notebook and provide show and servable methods.
"""
def __panel__(self) -> Viewable:
"""
Subclasses should return a Panel component to be rendered.
"""
raise NotImplementedError
def _create_view(self):
from .pane import panel
from .param import ParamMethod
if hasattr(self.__panel__, "_dinfo"):
view = ParamMethod(self.__panel__, lazy=True)
else:
view = panel(self.__panel__())
return view
[docs] def servable(
self, title: Optional[str]=None, location: bool | 'Location' = True,
area: str = 'main', target: Optional[str] = None
) -> Viewable:
return self._create_view().servable(title, location, area, target)
servable.__doc__ = ServableMixin.servable.__doc__
[docs] def show(
self, title: Optional[str] = None, port: int = 0, address: Optional[str] = None,
websocket_origin: Optional[str] = None, threaded: bool = False, verbose: bool = True,
open: bool = True, location: bool | 'Location' = True, **kwargs
) -> threading.Thread | 'Server':
return self._create_view().show(
title, port, address, websocket_origin, threaded,
verbose, open, location, **kwargs
)
show.__doc__ = ServableMixin.show.__doc__
def _repr_mimebundle_(self, include=None, exclude=None):
return self._create_view()._repr_mimebundle_(include, exclude)
__all__ = (
"Layoutable",
"Viewable",
"Viewer"
)
