"""
Templates allow multiple Panel objects to be embedded into custom HTML
documents.
"""
from __future__ import annotations
import os
import sys
import uuid
from functools import partial
from pathlib import Path, PurePath
from typing import (
IO, TYPE_CHECKING, Any, ClassVar, Literal,
)
import jinja2
import param
from bokeh.document.document import Document
from bokeh.models import LayoutDOM
from bokeh.settings import settings as _settings
from pyviz_comms import JupyterCommManager as _JupyterCommManager
from ..config import _base_config, config, panel_extension
from ..io.document import init_doc
from ..io.model import add_to_doc
from ..io.notebook import render_template
from ..io.notifications import NotificationArea
from ..io.resources import (
BUNDLE_DIR, CDN_DIST, JS_VERSION, ResourceComponent, _env,
component_resource_path, get_dist_path, loading_css, parse_template,
resolve_custom_path, use_cdn,
)
from ..io.save import save
from ..io.state import curdoc_locked, state
from ..layout import Column, GridSpec, ListLike
from ..models.comm_manager import CommManager
from ..pane import (
HTML, HoloViews, Str, panel as _panel,
)
from ..pane.image import ImageBase
from ..reactive import ReactiveHTML
from ..theme.base import (
THEMES, DefaultTheme, Design, Theme,
)
from ..util import isurl
from ..viewable import (
MimeRenderMixin, Renderable, ServableMixin, Viewable,
)
from ..widgets import Button
from ..widgets.indicators import BooleanIndicator, LoadingSpinner
if TYPE_CHECKING:
from bokeh.model import Model
from bokeh.server.contexts import BokehSessionContext
from jinja2 import Template as _Template
from pyviz_comms import Comm
from typing_extensions import Self
from ..io.location import Location
from ..io.resources import ResourcesType
_server_info: str = (
'Running server: '
'https://localhost:{port}'
)
FAVICON_URL: str = "/static/extensions/panel/images/favicon.ico"
class BaseTemplate(param.Parameterized, MimeRenderMixin, ServableMixin, ResourceComponent):
config = param.ClassSelector(default=_base_config(), class_=_base_config,
constant=True, doc="""
Configuration object declaring custom CSS and JS files to load
specifically for this template.""")
design = param.ClassSelector(class_=Design, default=Design,
is_instance=False, instantiate=False, doc="""
A Design applies themes to a template.""")
location = param.Boolean(default=False, doc="""
Whether to add a Location component to this Template.
Note if this is set to true, the Jinja2 template must
either insert all available roots or explicitly embed
the location root with : {{ embed(roots.location) }}.""")
theme = param.ClassSelector(class_=Theme, default=DefaultTheme,
constant=True, is_instance=False, instantiate=False)
# Dictionary of property overrides by Viewable type
modifiers: ClassVar[dict[type[Viewable], dict[str, Any]]] = {}
#############
# Resources #
#############
# pathlib.Path pointing to local CSS file(s)
_css: ClassVar[list[Path | str]] = []
# pathlib.Path pointing to local JS file(s)
_js: ClassVar[Path | str | list[Path | str] | None] = None
# External resources
_resources = {
'css': {}, 'js': {}, 'js_modules': {}, 'tarball': {}
}
__abstract = True
def __init__(
self, template: str | _Template, items=None,
nb_template: str | _Template | None = None, **params
):
config_params = {
p: v for p, v in params.items() if p in _base_config.param
}
self._render_items: dict[str, tuple[Renderable, list[str]]] = {}
self._render_variables: dict[str, Any] = {}
super().__init__(**{
p: v for p, v in params.items() if p not in _base_config.param or p == 'name'
})
self.config.param.update(config_params)
if isinstance(template, str):
self._code: str | None = template
self.template = _env.from_string(template)
else:
self._code = None
self.template = template
if isinstance(nb_template, str):
self.nb_template = _env.from_string(nb_template)
else:
self.nb_template = nb_template or self.template
self._documents: list[Document] = []
self._refs: dict[Document, str] = {}
self._server = None
self._layout = self._build_layout()
self._setup_design()
@param.depends('design', watch=True)
def _setup_design(self):
self._design = self.design(theme=self.theme)
def _update_vars(self, *args) -> None:
"""
Updates the render variables before the template is rendered.
"""
def _build_layout(self) -> Column:
str_repr = Str(repr(self))
server_info = HTML('')
button = Button(name='Launch server')
def launch(event):
if self._server:
button.name = 'Launch server'
server_info.object = ''
self._server.stop()
self._server = None
else:
button.name = 'Stop server'
self._server = self._get_server(start=True, show=True)
server_info.object = _server_info.format(port=self._server.port)
button.param.watch(launch, 'clicks')
return Column(str_repr, server_info, button)
def __repr__(self) -> str:
spacer = '\n '
objs = spacer.join([
f'[{name}] {obj.__repr__(1)}' # type: ignore
for name, (obj, _) in self._render_items.items()
if not name.startswith('_')
])
return f'{type(self).__name__}{spacer}{objs}'
def _apply_root(self, name: str, model: Model, tags: list[str]) -> None:
pass
def _server_destroy(self, session_context: BokehSessionContext):
doc = session_context._document
if doc in state._templates:
del state._templates[doc]
ref = self._refs.pop(doc, None)
if ref:
state._fake_roots.remove(ref)
self._documents.remove(doc)
def _init_doc(
self, doc: Document | None = None, comm: Comm | None = None,
title: str | None = None, notebook: bool = False,
location: bool | Location = True
):
# Initialize document
document = init_doc(doc or curdoc_locked())
self._documents.append(document)
if document not in state._templates:
state._templates[document] = self
if location and self.location:
self._add_location(document, location)
document.on_session_destroyed(state._destroy_session) # type: ignore
document.on_session_destroyed(self._server_destroy) # type: ignore
if title or document.title == 'Bokeh Application':
title = title or 'Panel Application'
document.title = title
# Initialize fake root. This is needed to ensure preprocessors
# which assume that all models are owned by a single root can
# link objects across multiple roots in a template.
col = Column()
preprocess_root = col.get_root(document, comm, preprocess=False)
col._hooks.append(self._design._apply_hooks)
ref = preprocess_root.ref['id']
# Add all render items to the document
objs, models = [], []
stylesheets, sizing_modes = {}, {}
tracked_models: set[Model] = set()
for name, (obj, tags) in self._render_items.items():
# Render root without pre-processing
with config.set(design=self.design):
model = obj.get_root(document, comm, preprocess=False)
model.name = name
model.tags = model.tags + [tag for tag in tags if tag not in model.tags]
mref = model.ref['id']
if isinstance(model, LayoutDOM):
sizing_modes[mref] = model.sizing_mode
if self._design._apply_hooks not in obj._hooks:
obj._hooks.append(self._design._apply_hooks)
# Alias model ref with the fake root ref to ensure that
# pre-processor correctly operates on fake root
for sub in obj.select(Viewable):
submodel = sub._models.get(mref)
for stylesheet in getattr(sub, '_stylesheets', []):
if not stylesheet.endswith('.css'):
continue
sts_name = f'extra_{os.path.basename(stylesheet)}'
stylesheets[sts_name] = stylesheet
if submodel is None:
continue
sub._models[ref] = submodel
if isinstance(sub, HoloViews) and mref in sub._plots:
sub._plots[ref] = sub._plots.get(mref)
# Apply any template specific hooks to root
self._apply_root(name, model, tags)
# Add document
obj._documents[document] = model
objs.append(obj)
models.append(model)
tracked_models |= add_to_doc(model, document, hold=bool(comm), skip=tracked_models)
document.on_session_destroyed(obj._server_destroy) # type: ignore
# Here we ensure that the preprocessor is run across all roots
# and set up session cleanup hooks for the fake root.
state._fake_roots.append(ref) # Ensure no update is run
state._views[ref] = (col, preprocess_root, document, comm)
col.objects = objs
preprocess_root.children[:] = models
preprocess_root.document = document
self._design.apply(col, preprocess_root, isolated=False)
col._preprocess(preprocess_root)
col._documents[document] = preprocess_root
document.on_session_destroyed(col._server_destroy) # type: ignore
# Apply the jinja2 template and update template variables
if notebook:
document.template = self.nb_template
else:
document.template = self.template
self._update_vars()
resources = self.resolve_resources(extras={'css': stylesheets})
document._template_variables['template_resources'] = resources
document._template_variables['sizing_modes'] = sizing_modes
document._template_variables.update(self._render_variables)
return document
def _repr_mimebundle_(
self, include=None, exclude=None
) -> tuple[dict[str, str], dict[str, dict[str, str]]] | None:
loaded = panel_extension._loaded
if not loaded and 'holoviews' in sys.modules:
import holoviews as hv
loaded = hv.extension._loaded
if not loaded:
param.main.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
try:
assert get_ipython().kernel is not None # type: ignore # noqa
state._comm_manager = _JupyterCommManager
except Exception:
pass
from IPython.display import display
doc = Document()
comm = state._comm_manager.get_server_comm()
self._init_doc(doc, comm, notebook=True)
ref = doc.roots[0].ref['id']
manager = CommManager(
comm_id=comm.id, plot_id=ref, name='comm_manager'
)
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),
on_open=lambda _: comm.init()
)
manager.client_comm_id = client_comm.id
doc.add_root(manager)
if config.console_output != 'disable':
handle = display(display_id=uuid.uuid4().hex)
state._handles[ref] = (handle, [])
return render_template(doc, comm, manager)
#----------------------------------------------------------------
# Public API
#----------------------------------------------------------------
def resolve_resources(
self,
cdn: bool | Literal['auto'] = 'auto',
extras: dict[str, dict[str, str]] | None = None
) -> ResourcesType:
"""
Resolves the resources required for this template component.
Parameters
----------
cdn: bool | Literal['auto']
Whether to load resources from CDN or local server. If set
to 'auto' value will be automatically determine based on
global settings.
extras: dict[str, dict[str, str]] | None
Additional resources to add to the bundle. Valid resource
types include js, js_modules and css.
Returns
-------
Dictionary containing JS and CSS resources.
"""
cls = type(self)
resource_types = super().resolve_resources(cdn=cdn, extras=extras)
js_files = resource_types['js']
js_modules = resource_types['js_modules']
css_files = resource_types['css']
raw_css = resource_types['raw_css']
clsname = cls.__name__
name = clsname.lower()
cdn = use_cdn() if cdn == 'auto' else cdn
dist_path = get_dist_path(cdn=cdn)
version_suffix = f'?v={JS_VERSION}'
css_files['loading'] = f'{dist_path}css/loading.css{version_suffix}'
raw_css.extend(list(self.config.raw_css) + [loading_css(
config.loading_spinner, config.loading_color, config.loading_max_height
)])
for rname, res in self._design.resolve_resources(cdn).items():
if isinstance(res, dict):
resource_types[rname].update(res) # type: ignore
else:
resource_types[rname] += [ # type: ignore
r for r in res if res not in resource_types[rname] # type: ignore
]
for rname, js in self.config.js_files.items():
if '//' not in js and state.rel_path:
js = f'{state.rel_path}/{js}'
js_files[rname] = js
for rname, js in self.config.js_modules.items():
if '//' not in js and state.rel_path:
js = f'{state.rel_path}/{js}'
js_modules[rname] = js
for i, css in enumerate(list(self.config.css_files)):
if '//' not in css and state.rel_path:
css = f'{state.rel_path}/{css}'
css_files[f'config_{i}'] = css
# CSS files
base_css = self._css
if not isinstance(base_css, list):
base_css = [base_css] if base_css else []
for css in base_css:
tmpl_name = name
for scls in cls.__mro__[1:]:
if not issubclass(scls, BaseTemplate):
continue
elif scls._css is None:
break
tmpl_css = scls._css if isinstance(scls._css, list) else [scls._css] # type: ignore
if css in tmpl_css:
tmpl_name = scls.__name__.lower()
css_file = os.path.basename(css)
if (BUNDLE_DIR / tmpl_name / css_file).is_file():
css_files[f'base_{css_file}'] = f'{dist_path}bundled/{tmpl_name}/{css_file}{version_suffix}'
elif isurl(css):
css_files[f'base_{css_file}'] = css
elif resolve_custom_path(self, css):
css_files[f'base_{css_file}' ] = component_resource_path(self, '_css', css)
# JS files
base_js = self._js
if not isinstance(base_js, list):
base_js = [base_js] if base_js else []
for js in base_js:
tmpl_name = name
for cls in type(self).__mro__[1:-5]:
if not issubclass(cls, BaseTemplate):
continue
elif cls._js is None:
break
tmpl_js = cls._js if isinstance(cls._js, list) else [cls._js]
if js in tmpl_js:
tmpl_name = cls.__name__.lower()
js_name = os.path.basename(js)
if (BUNDLE_DIR / tmpl_name / js_name).is_file():
js_files[f'base_{js_name}'] = dist_path + f'bundled/{tmpl_name}/{js_name}'
elif isurl(js):
js_files[f'base_{js_name}'] = js
elif resolve_custom_path(self, js):
js_files[f'base_{js_name}'] = component_resource_path(self, '_js', js)
return resource_types
def save(
self, filename: str | os.PathLike | IO, title: str | None = None,
resources=None, embed: bool = False, max_states: int = 1000,
max_opts: int = 3, embed_json: bool = False, json_prefix: str='',
save_path: str='./', load_path: str | None = None
) -> None:
"""
Saves Panel objects to file.
Parameters
----------
filename: string 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)
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.
"""
if embed:
raise ValueError("Embedding is not yet supported on Template.")
return save(
self, filename, title, resources, self.template,
self._render_variables, embed, max_states, max_opts,
embed_json, json_prefix, save_path, load_path
)
def server_doc(
self, doc: Document | None = None, title: str | None = None,
location: bool | Location = True
) -> Document:
"""
Returns a servable Document with the template attached.
Parameters
----------
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.
"""
return self._init_doc(doc, title=title, location=location)
def servable(
self, title: str | None = None, location: bool | Location = True,
area: str = 'main', target: str | None = None
) -> Self:
"""
Serves the template and returns self to allow it to display
itself in a notebook context.
Parameters
----------
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 template object
"""
doc = curdoc_locked()
if doc and doc.session_context and config.template:
raise RuntimeError(
'Cannot mark template as servable if a global template '
'is defined. Either explicitly construct a template and '
'serve it OR set `pn.config.template`, whether directly '
'or via `pn.extension(template=...)`, not both.'
)
return super().servable(title, location, area, target)
def select(self, selector=None):
"""
Iterates over the Template and any potential children in the
applying the Selector.
Parameters
----------
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)
"""
objects = []
for obj, _ in self._render_items.values():
objects += obj.select(selector)
return objects
class TemplateActions(ReactiveHTML):
"""
A component added to templates that allows triggering events such
as opening and closing a modal.
"""
open_modal = param.Integer(default=0)
close_modal = param.Integer(default=0)
_template: ClassVar[str] = ""
_scripts: ClassVar[dict[str, list[str] | str]] = {
'open_modal': ["""
document.getElementById('pn-Modal').style.display = 'block'
window.dispatchEvent(new Event('resize'));
"""],
'close_modal': ["document.getElementById('pn-Modal').style.display = 'none'"],
}
class BasicTemplate(BaseTemplate):
"""
BasicTemplate provides a baseclass for templates with a basic
organization including a header, sidebar and main area. Unlike the
more generic Template class these default templates make it easy
for a user to generate an application with a polished look and
feel without having to write any Jinja2 template themselves.
"""
busy_indicator = param.ClassSelector(default=LoadingSpinner(width=20, height=20),
class_=BooleanIndicator, constant=True,
allow_None=True, doc="""
Visual indicator of application busy state.""")
collapsed_sidebar = param.Selector(default=False, constant=True, doc="""
Whether the sidebar (if present) is initially collapsed.""")
header = param.ClassSelector(class_=ListLike, constant=True, doc="""
A list-like container which populates the header bar.""")
main = param.ClassSelector(class_=ListLike, constant=True, doc="""
A list-like container which populates the main area.""")
main_max_width = param.String(default="", doc="""
The maximum width of the main area. For example '800px' or '80%'.
If the string is '' (default) no max width is set.""")
sidebar = param.ClassSelector(class_=ListLike, constant=True, doc="""
A list-like container which populates the sidebar.""")
sidebar_width = param.Integer(default=330, doc="""
The width of the sidebar in pixels. Default is 330.""")
modal = param.ClassSelector(class_=ListLike, constant=True, doc="""
A list-like container which populates the modal""")
notifications = param.ClassSelector(class_=NotificationArea, constant=True, doc="""
The NotificationArea instance attached to this template.
Automatically added if config.notifications is set, but may
also be provided explicitly.""")
logo = param.String(doc="""
URI of logo to add to the header (if local file, logo is
base64 encoded as URI). Default is '', i.e. not shown.""")
favicon = param.String(default=FAVICON_URL, doc="""
URI of favicon to add to the document head (if local file, favicon is
base64 encoded as URI).""")
title = param.String(default="Panel Application", doc="""
A title to show in the header. Also added to the document head
meta settings and as the browser tab title.""")
site = param.String(default="", doc="""
Name of the site. Will be shown in the header and link to the
'site_url'. Default is '', i.e. not shown.""")
site_url = param.String(default="/", doc="""
Url of the site and logo. Default is '/'.""")
manifest = param.String(default=None, doc="""
Manifest to add to site.""")
meta_description = param.String(doc="""
A meta description to add to the document head for search
engine optimization. For example 'P.A. Nelson'.""")
meta_keywords = param.String(doc="""
Meta keywords to add to the document head for search engine
optimization.""")
meta_author = param.String(doc="""
A meta author to add to the the document head for search
engine optimization. For example 'P.A. Nelson'.""")
meta_refresh = param.String(doc="""
A meta refresh rate to add to the document head. For example
'30' will instruct the browser to refresh every 30
seconds. Default is '', i.e. no automatic refresh.""")
meta_viewport = param.String(doc="""
A meta viewport to add to the header.""")
base_url = param.String(doc="""
Specifies the base URL for all relative URLs in a
page. Default is '', i.e. not the domain.""")
base_target = param.Selector(default="_self",
objects=["_blank", "_self", "_parent", "_top"], doc="""
Specifies the base Target for all relative URLs in a page.""")
header_background = param.String(doc="""
Optional header background color override.""")
header_color = param.String(doc="""
Optional header text color override.""")
location = param.Boolean(default=True, readonly=True)
_actions = param.ClassSelector(default=TemplateActions(), class_=TemplateActions)
#############
# Resources #
#############
# pathlib.Path pointing to local Jinja2 template
_template: ClassVar[Path | None] = None
__abstract = True
def __init__(self, **params):
tmpl_string = self._template.read_text(encoding='utf-8')
try:
template = _env.get_template(str(self._template.relative_to(Path(__file__).parent)))
except (jinja2.exceptions.TemplateNotFound, ValueError):
template = parse_template(tmpl_string)
if 'header' not in params:
params['header'] = ListLike()
else:
params['header'] = self._get_params(params['header'], self.param.header.class_)
if 'main' not in params:
params['main'] = ListLike()
else:
params['main'] = self._get_params(params['main'], self.param.main.class_)
if 'sidebar' not in params:
params['sidebar'] = ListLike()
else:
params['sidebar'] = self._get_params(params['sidebar'], self.param.sidebar.class_)
if 'modal' not in params:
params['modal'] = ListLike()
else:
params['modal'] = self._get_params(params['modal'], self.param.modal.class_)
if 'theme' in params:
if isinstance(params['theme'], str):
params['theme'] = THEMES[params['theme']]
else:
params['theme'] = THEMES[config.theme]
if 'favicon' in params and isinstance(params['favicon'], PurePath):
params['favicon'] = str(params['favicon'])
if 'notifications' not in params and config.notifications:
params['notifications'] = state.notifications if state.curdoc else NotificationArea()
super().__init__(template=template, **params)
self._js_area = HTML(margin=0, width=0, height=0)
state_roots = '{% block state_roots %}' in tmpl_string
if state_roots or 'embed(roots.js_area)' in tmpl_string:
self._render_items['js_area'] = (self._js_area, [])
if state_roots or 'embed(roots.actions)' in tmpl_string:
self._render_items['actions'] = (self._actions, [])
if (state_roots or 'embed(roots.notifications)' in tmpl_string) and self.notifications:
self._render_items['notifications'] = (self.notifications, [])
self._render_variables['notifications'] = True
if config.browser_info and ('embed(roots.browser_info)' in tmpl_string or state_roots) and state.browser_info:
self._render_items['browser_info'] = (state.browser_info, [])
self._render_variables['browser_info'] = True
self._update_busy()
self.main.param.watch(self._update_render_items, ['objects'])
self.modal.param.watch(self._update_render_items, ['objects'])
self.sidebar.param.watch(self._update_render_items, ['objects'])
self.header.param.watch(self._update_render_items, ['objects'])
self.main.param.trigger('objects')
self.sidebar.param.trigger('objects')
self.header.param.trigger('objects')
self.modal.param.trigger('objects')
def _init_doc(
self, doc: Document | None = None, comm: Comm | None = None,
title: str | None=None, notebook: bool = False, location: bool | Location = True
) -> Document:
title = self.title if self.title != self.param.title.default else title
if self.busy_indicator:
state.sync_busy(self.busy_indicator)
document = super()._init_doc(doc, comm, title, notebook, location)
if self.notifications:
state._notifications[document] = self.notifications
if self._design.theme.bokeh_theme:
document.theme = self._design.theme.bokeh_theme
return document
def _update_vars(self, *args) -> None:
super()._update_vars(*args)
self._render_variables['app_title'] = self.title
self._render_variables['meta_name'] = self.title
self._render_variables['site_title'] = self.site
self._render_variables['site_url'] = self.site_url
self._render_variables['manifest'] = self.manifest
self._render_variables['meta_description'] = self.meta_description
self._render_variables['meta_keywords'] = self.meta_keywords
self._render_variables['meta_author'] = self.meta_author
self._render_variables['meta_refresh'] = self.meta_refresh
self._render_variables['meta_viewport'] = self.meta_viewport
self._render_variables['base_url'] = self.base_url
self._render_variables['base_target'] = self.base_target
if os.path.isfile(self.logo):
img = _panel(self.logo)
if not isinstance(img, ImageBase):
raise ValueError(f"Could not determine file type of logo: {self.logo}.")
imgdata = img._data(img.object)
if imgdata:
logo = img._b64(imgdata)
else:
raise ValueError(f"Could not embed logo {self.logo}.")
else:
logo = self.logo
if os.path.isfile(self.favicon):
img = _panel(self.favicon)
if not isinstance(img, ImageBase):
raise ValueError(f"Could not determine file type of favicon: {self.favicon}.")
imgdata = img._data(img.object)
if imgdata:
favicon = img._b64(imgdata)
else:
raise ValueError(f"Could not embed favicon {self.favicon}.")
else:
if _settings.resources(default='server') == 'cdn' and self.favicon == FAVICON_URL:
favicon = CDN_DIST + "images/favicon.ico"
else:
favicon = self.favicon
self._render_variables['app_logo'] = logo
self._render_variables['app_favicon'] = favicon
self._render_variables['app_favicon_type'] = self._get_favicon_type(self.favicon)
self._render_variables['header_background'] = self.header_background
self._render_variables['header_color'] = self.header_color
self._render_variables['main_max_width'] = self.main_max_width
self._render_variables['sidebar_width'] = self.sidebar_width
self._render_variables['theme'] = self._design.theme
self._render_variables['collapsed_sidebar'] = self.collapsed_sidebar
def _update_busy(self) -> None:
if self.busy_indicator:
self._render_items['busy_indicator'] = (self.busy_indicator, [])
elif 'busy_indicator' in self._render_items:
del self._render_items['busy_indicator']
self._render_variables['busy'] = self.busy_indicator is not None
def _update_render_items(self, event: param.parameterized.Event) -> None:
if event.obj is self and event.name == 'busy_indicator':
return self._update_busy()
if event.obj is self.main:
tag = 'main'
elif event.obj is self.sidebar:
tag = 'nav'
elif event.obj is self.header:
tag = 'header'
elif event.obj is self.modal:
tag = 'modal'
old = event.old if isinstance(event.old, list) else list(event.old.values())
for obj in old:
ref = f'{tag}-{str(id(obj))}'
if ref in self._render_items:
del self._render_items[ref]
new = event.new if isinstance(event.new, list) else event.new.values()
if self._design.theme.bokeh_theme:
for o in new:
if o in old:
continue
for hvpane in o.select(HoloViews):
hvpane.theme = self._design.theme.bokeh_theme
labels = {}
for obj in new:
ref = f'{tag}-{str(id(obj))}'
if obj.name.startswith(type(obj).__name__):
labels[ref] = 'Content'
else:
labels[ref] = obj.name
self._render_items[ref] = (obj, [tag])
tags = [tags for _, tags in self._render_items.values()]
self._render_variables['nav'] = any('nav' in ts for ts in tags)
self._render_variables['header'] = any('header' in ts for ts in tags)
self._render_variables['root_labels'] = labels
def _server_destroy(self, session_context: BokehSessionContext):
super()._server_destroy(session_context)
if not self._documents and self.busy_indicator in state._indicators:
state._indicators.remove(self.busy_indicator)
def open_modal(self) -> None:
"""
Opens the modal area
"""
self._actions.open_modal += 1
def close_modal(self) -> None:
"""
Closes the modal area
"""
self._actions.close_modal += 1
@staticmethod
def _get_favicon_type(favicon) -> str:
if not favicon:
return ""
elif favicon.endswith(".png"):
return "image/png"
elif favicon.endswith("jpg"):
return "image/jpg"
elif favicon.endswith("gif"):
return "image/gif"
elif favicon.endswith("svg"):
return "image/svg"
elif favicon.endswith("ico"):
return "image/x-icon"
else:
raise ValueError("favicon type not supported.")
@staticmethod
def _get_params(value, class_):
if isinstance(value, class_):
return value
if isinstance(value, tuple):
value = [*value]
elif not isinstance(value, list):
value = [value]
# Important to fx. convert @param.depends functions
value = [_panel(item) for item in value]
if class_ is ListLike:
return ListLike(objects=value)
if class_ is GridSpec:
grid = GridSpec(ncols=12, mode='override')
for index, item in enumerate(value):
grid[index, :]=item
return grid
return value
class Template(BaseTemplate):
"""
A Template is a high-level component to render multiple Panel
objects into a single HTML document defined through a Jinja2
template. The Template object is given a Jinja2 template and then
allows populating this template by adding Panel objects, which are
given unique names. These unique names may then be referenced in
the template to insert the rendered Panel object at a specific
location. For instance, given a Jinja2 template that defines roots
A and B like this:
{{ embed(roots.A) }}
{{ embed(roots.B) }}
We can then populate the template by adding panel 'A' and 'B' to
the Template object:
template.add_panel('A', pn.panel('A'))
template.add_panel('B', pn.panel('B'))
Once a template has been fully populated it can be rendered using
the same API as other Panel objects. Note that all roots that have
been declared using the {{ embed(roots.A) }} syntax in the Jinja2
template must be defined when rendered.
Since embedding complex CSS frameworks inside a notebook can have
undesirable side-effects and a notebook does not afford the same
amount of screen space a Template may given separate template
and nb_template objects. This allows for different layouts when
served as a standalone server and when used in the notebook.
"""
def __init__(
self, template: str | _Template, nb_template: str | _Template | None = None,
items: dict[str, Any] | None = None, **params
):
super().__init__(template=template, nb_template=nb_template, items=items, **params)
items = {} if items is None else items
for name, item in items.items():
self.add_panel(name, item)
#----------------------------------------------------------------
# Public API
#----------------------------------------------------------------
def add_panel(self, name: str, panel: Any, tags: list[str] = []) -> None:
"""
Add panels to the Template, which may then be referenced by
the given name using the jinja2 embed macro.
Parameters
----------
name : str
The name to refer to the panel by in the template
panel : panel.Viewable
A Panel component to embed in the template.
"""
if name in self._render_items:
raise ValueError(f'The name {name} has already been used for '
'another panel. Ensure each panel '
'has a unique name by which it can be '
'referenced in the template.')
rendered = _panel(panel)
if not isinstance(rendered, Viewable):
raise ValueError(f"Cannot add {type(panel).__name__!r} type")
self._render_items[name] = (rendered, tags)
self._layout[0].object = repr(self) # type: ignore
def add_variable(self, name: str, value: Any) -> None:
"""
Add parameters to the template, which may then be referenced
by the given name in the Jinja2 template.
Parameters
----------
name : str
The name to refer to the panel by in the template
value : object
Any valid Jinja2 variable type.
"""
if name in self._render_variables:
raise ValueError(f'The name {name} has already been used for '
'another variable. Ensure each variable '
'has a unique name by which it can be '
'referenced in the template.')
self._render_variables[name] = value