"""
Patches bokeh resources to make it easy to add external JS and CSS
resources via the panel.config object.
"""
from __future__ import annotations
import importlib
import json
import logging
import mimetypes
import os
import pathlib
import re
import textwrap
from base64 import b64encode
from collections import OrderedDict
from contextlib import contextmanager
from functools import lru_cache
from pathlib import Path
from typing import (
TYPE_CHECKING, Dict, List, Literal, TypedDict,
)
import param
from bokeh.embed.bundle import (
CSS_RESOURCES as BkCSS_RESOURCES, Bundle as BkBundle, _bundle_extensions,
_use_mathjax, bundle_models, extension_dirs,
)
from bokeh.model import Model
from bokeh.models import ImportedStyleSheet
from bokeh.resources import Resources as BkResources, _get_server_urls
from bokeh.settings import settings as _settings
from jinja2.environment import Environment
from jinja2.loaders import FileSystemLoader
from markupsafe import Markup
from ..config import config, panel_extension as extension
from ..util import isurl, url_path
from .loading import LOADING_INDICATOR_CSS_CLASS
from .state import state
if TYPE_CHECKING:
from bokeh.resources import Urls
class ResourcesType(TypedDict):
css: Dict[str, str]
js: Dict[str, str]
js_modules: Dict[str, str]
raw_css: List[str]
logger = logging.getLogger(__name__)
ResourceAttr = Literal["__css__", "__javascript__"]
with open(Path(__file__).parent.parent / 'package.json') as f:
package_json = json.load(f)
JS_VERSION = package_json['version'].split('+')[0]
[docs]def get_env():
''' Get the correct Jinja2 Environment, also for frozen scripts.
'''
local_path = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '_templates'))
return Environment(loader=FileSystemLoader(local_path))
def conffilter(value):
return json.dumps(OrderedDict(value)).replace('"', '\'')
_env = get_env()
_env.trim_blocks = True
_env.lstrip_blocks = True
_env.filters['json'] = lambda obj: Markup(json.dumps(obj))
_env.filters['conffilter'] = conffilter
_env.filters['sorted'] = sorted
# Handle serving of the panel extension before session is loaded
RESOURCE_MODE = 'server'
PANEL_DIR = Path(__file__).parent.parent
DIST_DIR = PANEL_DIR / 'dist'
BUNDLE_DIR = DIST_DIR / 'bundled'
ASSETS_DIR = PANEL_DIR / 'assets'
INDEX_TEMPLATE = _env.get_template('convert_index.html')
BASE_TEMPLATE = _env.get_template('base.html')
ERROR_TEMPLATE = _env.get_template('error.html')
BASIC_LOGIN_TEMPLATE = _env.get_template('basic_login.html')
DEFAULT_TITLE = "Panel Application"
JS_RESOURCES = _env.get_template('js_resources.html')
CDN_URL = f"https://cdn.holoviz.org/panel/{JS_VERSION}/"
CDN_DIST = f"{CDN_URL}dist/"
DOC_DIST = "https://panel.holoviz.org/_static/"
LOCAL_DIST = "static/extensions/panel/"
COMPONENT_PATH = "components/"
BK_PREFIX_RE = re.compile('\.bk\.')
RESOURCE_URLS = {
'font-awesome': {
'zip': 'https://use.fontawesome.com/releases/v5.15.4/fontawesome-free-5.15.4-web.zip',
'src': 'fontawesome-free-5.15.4-web/',
'exclude': ['*.svg', '*.scss', '*.less']
},
'bootstrap4': {
'tar': 'https://registry.npmjs.org/bootstrap/-/bootstrap-4.6.1.tgz',
'src': 'package/dist',
'exclude': [],
'dest': ''
},
'bootstrap5': {
'tar': 'https://registry.npmjs.org/bootstrap/-/bootstrap-5.3.0-alpha1.tgz',
'src': 'package/dist',
'exclude': [],
'dest': ''
},
'jQuery': {
'tar': 'https://registry.npmjs.org/jquery/-/jquery-3.5.1.tgz',
'src': 'package/dist',
'exclude': [],
'dest': ''
}
}
CSS_URLS = {
'font-awesome': f'{CDN_DIST}bundled/font-awesome/css/all.min.css',
'bootstrap4': f'{CDN_DIST}bundled/bootstrap4/css/bootstrap.min.css',
'bootstrap5': f'{CDN_DIST}bundled/bootstrap5/css/bootstrap.min.css'
}
JS_URLS = {
'jQuery': f'{CDN_DIST}bundled/jquery/jquery.slim.min.js',
'bootstrap4': f'{CDN_DIST}bundled/bootstrap4/js/bootstrap.bundle.min.js',
'bootstrap5': f'{CDN_DIST}bundled/bootstrap5/js/bootstrap.bundle.min.js'
}
extension_dirs['panel'] = str(DIST_DIR)
mimetypes.add_type("application/javascript", ".js")
@contextmanager
def set_resource_mode(mode):
global RESOURCE_MODE
old_resources = _settings.resources._user_value
old_mode = RESOURCE_MODE
_settings.resources = RESOURCE_MODE = mode
try:
yield
finally:
RESOURCE_MODE = old_mode
_settings.resources.set_value(old_resources)
def use_cdn() -> bool:
return _settings.resources(default="server") != 'server'
def get_dist_path(cdn: bool | Literal['auto'] = 'auto') -> str:
cdn = use_cdn() if cdn == 'auto' else cdn
if cdn:
dist_path = CDN_DIST
elif state.rel_path:
dist_path = f'{state.rel_path}/{LOCAL_DIST}'
else:
dist_path = f'{LOCAL_DIST}'
return dist_path
def is_cdn_url(url) -> bool:
return isurl(url) and url.startswith(CDN_DIST)
[docs]def process_raw_css(raw_css):
"""
Converts old-style Bokeh<3 compatible CSS to Bokeh 3 compatible CSS.
"""
return [BK_PREFIX_RE.sub('.', css) for css in raw_css]
@lru_cache(maxsize=None)
def loading_css(loading_spinner, color, max_height):
with open(ASSETS_DIR / f'{loading_spinner}_spinner.svg', encoding='utf-8') as f:
svg = f.read().replace('\n', '').format(color=color)
b64 = b64encode(svg.encode('utf-8')).decode('utf-8')
return textwrap.dedent(f"""
:host(.{LOADING_INDICATOR_CSS_CLASS}.pn-{loading_spinner}):before, .pn-loading.pn-{loading_spinner}:before {{
background-image: url("data:image/svg+xml;base64,{b64}");
background-size: auto calc(min(50%, {max_height}px));
}}""")
[docs]def resolve_custom_path(
obj, path: str | os.PathLike, relative: bool = False
) -> pathlib.Path | None:
"""
Attempts to resolve a path relative to some component.
Arguments
---------
obj: type | object
The component to resolve the path relative to.
path: str | os.PathLike
Absolute or relative path to a resource.
relative: bool
Whether to return a relative path.
Returns
-------
path: pathlib.Path | None
"""
if not path:
return
if not isinstance(obj, type):
obj = type(obj)
try:
mod = importlib.import_module(obj.__module__)
module_path = Path(mod.__file__).parent
assert module_path.exists()
except Exception:
return None
path = pathlib.Path(path)
if path.is_absolute():
abs_path = path
else:
abs_path = module_path / path
if not abs_path.is_file():
return None
abs_path = abs_path.resolve()
if not relative:
return abs_path
return os.path.relpath(abs_path, module_path)
[docs]def component_resource_path(component, attr, path):
"""
Generates a canonical URL for a component resource.
To be used in conjunction with the `panel.io.server.ComponentResourceHandler`
which allows dynamically resolving resources defined on components.
"""
if not isinstance(component, type):
component = type(component)
component_path = COMPONENT_PATH
if state.rel_path:
component_path = f"{state.rel_path}/{component_path}"
rel_path = str(resolve_custom_path(component, path, relative=True)).replace(os.path.sep, '/')
return f'{component_path}{component.__module__}/{component.__name__}/{attr}/{rel_path}'
def patch_stylesheet(stylesheet, dist_url):
url = stylesheet.url
if url.startswith(CDN_DIST+dist_url) and dist_url != CDN_DIST:
patched_url = url.replace(CDN_DIST+dist_url, dist_url)
elif url.startswith(CDN_DIST) and dist_url != CDN_DIST:
patched_url = url.replace(CDN_DIST, dist_url)
else:
return
try:
stylesheet.url = patched_url
except Exception:
pass
[docs]def resolve_stylesheet(cls, stylesheet: str, attribute: str | None = None):
"""
Resolves a stylesheet definition, e.g. originating on a component
Reactive._stylesheets or a Design.modifiers attribute. Stylesheets
may be defined as one of the following:
- Absolute URL defined with http(s) protocol
- A path relative to the component
Arguments
---------
cls: type | object
Object or class defining the stylesheet
stylesheet: str
The stylesheet definition
"""
stylesheet = str(stylesheet)
if not stylesheet.startswith('http') and attribute and (custom_path:= resolve_custom_path(cls, stylesheet)):
if not state._is_pyodide and state.curdoc and state.curdoc.session_context:
stylesheet = component_resource_path(cls, attribute, stylesheet)
else:
stylesheet = custom_path.read_text(encoding='utf-8')
return stylesheet
[docs]def patch_model_css(root, dist_url):
"""
Temporary patch for Model.css property used by Panel to provide
stylesheets for components.
ALERT: Should find better solution before official Bokeh 3.x compatible release
"""
# Patch model CSS properties
doc = root.document
if doc:
held = doc.callbacks.hold_value
events = list(doc.callbacks._held_events)
doc.hold()
for stylesheet in root.select({'type': ImportedStyleSheet}):
patch_stylesheet(stylesheet, dist_url)
if doc:
doc.callbacks._held_events = events
if held:
doc.callbacks._hold = held
else:
doc.unhold()
def global_css(name):
if RESOURCE_MODE == 'server':
return f'static/extensions/panel/css/{name}.css'
else:
return f'{CDN_DIST}css/{name}.css'
def bundled_files(model, file_type='javascript'):
name = model.__name__.lower()
bdir = BUNDLE_DIR / name
shared = list((JS_URLS if file_type == 'javascript' else CSS_URLS).values())
files = []
for url in getattr(model, f"__{file_type}_raw__", []):
if url.startswith(CDN_DIST):
filepath = url.replace(f'{CDN_DIST}bundled/', '')
elif url.startswith(config.npm_cdn):
filepath = url.replace(config.npm_cdn, '')[1:]
else:
filepath = url_path(url)
test_filepath = filepath.split('?')[0]
if url in shared:
prefixed = filepath
test_path = BUNDLE_DIR / test_filepath
elif not test_filepath.replace('/', '').startswith(f'{name}/'):
prefixed = f'{name}/{test_filepath}'
test_path = bdir / test_filepath
else:
prefixed = test_filepath
test_path = BUNDLE_DIR / test_filepath
if test_path.is_file():
if RESOURCE_MODE == 'server':
files.append(f'static/extensions/panel/bundled/{prefixed}')
elif filepath == test_filepath:
files.append(f'{CDN_DIST}bundled/{prefixed}')
else:
files.append(url)
else:
files.append(url)
return files
def bundle_resources(roots, resources, notebook=False, reloading=False, enable_mathjax='auto'):
from ..config import panel_extension as ext
global RESOURCE_MODE
if not isinstance(resources, Resources):
resources = Resources.from_bokeh(resources, notebook=notebook)
js_resources = css_resources = resources
RESOURCE_MODE = mode = js_resources.mode if resources is not None else "inline"
js_files = []
js_raw = []
css_files = []
css_raw = []
if isinstance(enable_mathjax, bool):
use_mathjax = enable_mathjax
elif roots:
use_mathjax = _use_mathjax(roots) or 'mathjax' in ext._loaded_extensions
else:
use_mathjax = False
if js_resources:
js_resources = js_resources.clone()
if not use_mathjax and "bokeh-mathjax" in js_resources.components:
js_resources.components.remove("bokeh-mathjax")
if reloading:
js_resources.components.clear()
js_files.extend(js_resources.js_files)
js_raw.extend(js_resources.js_raw)
css_files.extend(css_resources.css_files)
css_raw.extend(css_resources.css_raw)
extensions = _bundle_extensions(None, js_resources)
if reloading:
extensions = [
ext for ext in extensions if not ext.cdn_url.startswith('https://unpkg.com/@holoviz/panel@')
]
extra_js = []
if mode == "inline":
js_raw.extend([ Resources._inline(bundle.artifact_path) for bundle in extensions ])
elif mode == "server":
for bundle in extensions:
server_url = bundle.server_url
if resources.root_url and not resources.absolute:
server_url = server_url.replace(resources.root_url, '')
js_files.append(server_url)
elif mode == "cdn":
for bundle in extensions:
if bundle.cdn_url is not None:
extra_js.append(bundle.cdn_url)
else:
js_raw.append(Resources._inline(bundle.artifact_path))
else:
extra_js.extend([ bundle.artifact_path for bundle in extensions ])
js_files += resources.adjust_paths(extra_js)
ext = bundle_models(None)
if ext is not None:
js_raw.append(ext)
hashes = js_resources.hashes if js_resources else {}
return Bundle(
css_files=css_files,
css_raw=css_raw,
hashes=hashes,
js_files=js_files,
js_raw=js_raw,
js_module_exports=resources.js_module_exports,
js_modules=resources.js_modules,
notebook=notebook,
)
[docs]class ResourceComponent:
"""
Mix-in class for components that define a set of resources
that have to be resolved.
"""
_resources = {
'css': {},
'font': {},
'js': {},
'js_modules': {},
'raw_css': [],
}
@classmethod
def _resolve_resource(cls, resource_type: str, resource: str, cdn: bool = False):
dist_path = get_dist_path(cdn=cdn)
if resource.startswith(CDN_DIST):
resource_path = resource.replace(f'{CDN_DIST}bundled/', '')
elif resource.startswith(config.npm_cdn):
resource_path = resource.replace(config.npm_cdn, '')[1:]
elif resource.startswith('http:'):
resource_path = url_path(resource)
else:
resource_path = resource
if resource_type == 'js_modules' and not (state.rel_path or cdn):
prefixed_dist = f'./{dist_path}'
else:
prefixed_dist = dist_path
bundlepath = BUNDLE_DIR / resource_path.replace('/', os.path.sep)
# Windows may trigger OSError: [WinError 123]
try:
is_file = bundlepath.is_file()
except Exception:
is_file = False
if is_file:
return f'{prefixed_dist}bundled/{resource_path}'
elif isurl(resource):
return resource
elif resolve_custom_path(cls, resource):
return component_resource_path(
cls, f'_resources/{resource_type}', resource
)
[docs] def resolve_resources(self, cdn: bool | Literal['auto'] = 'auto') -> ResourcesType:
"""
Resolves the resources required for this component.
Arguments
---------
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.
Returns
-------
Dictionary containing JS and CSS resources.
"""
cls = type(self)
resources = {}
for rt, res in self._resources.items():
if not isinstance(res, dict):
continue
if rt == 'font':
rt = 'css'
res = {
name: url if isurl(url) else f'{cls.__name__.lower()}/{url}'
for name, url in res.items()
}
if rt in resources:
resources[rt] = dict(resources[rt], **res)
else:
resources[rt] = res
cdn = use_cdn() if cdn == 'auto' else cdn
resource_types: ResourcesType = {
'js': {},
'js_modules': {},
'css': {},
'raw_css': []
}
for resource_type in resource_types:
if resource_type not in resources or resource_type == 'raw_css':
continue
resource_files = resource_types[resource_type]
for rname, resource in resources[resource_type].items():
resolved_resource = self._resolve_resource(
resource_type, resource, cdn=cdn
)
if resolved_resource:
resource_files[rname] = resolved_resource
return resource_types
[docs]class Resources(BkResources):
def __init__(self, *args, absolute=False, notebook=False, **kwargs):
self.absolute = absolute
self.notebook = notebook
super().__init__(*args, **kwargs)
@classmethod
def from_bokeh(cls, bkr, absolute=False, notebook=False):
kwargs = {}
if bkr.mode.startswith("server"):
kwargs['root_url'] = bkr.root_url
components = bkr.components if hasattr(bkr, 'components_for') else bkr._components
return cls(
mode=bkr.mode, version=bkr.version, minified=bkr.minified,
log_level=bkr.log_level, notebook=notebook,
path_versioner=bkr.path_versioner,
components=components, base_dir=bkr.base_dir,
root_dir=bkr.root_dir, absolute=absolute, **kwargs
)
def _collect_external_resources(self, resource_attr: ResourceAttr) -> list[str]:
""" Collect external resources set on resource_attr attribute of all models."""
external_resources: list[str] = []
if state._extensions is not None:
external_modules = {
module: ext for ext, module in extension._imports.items()
}
else:
external_modules = None
for _, cls in sorted(Model.model_class_reverse_map.items(), key=lambda arg: arg[0]):
if external_modules is not None and cls.__module__ in external_modules:
if external_modules[cls.__module__] not in state._extensions:
continue
external: list[str] | str | None = getattr(cls, resource_attr, None)
if isinstance(external, str):
if external not in external_resources:
external_resources.append(external)
elif isinstance(external, list):
for e in external:
if e not in external_resources:
external_resources.append(e)
return external_resources
def _server_urls(self) -> Urls:
return _get_server_urls(
self.root_url if self.absolute else '',
False if self.dev else self.minified,
self.path_versioner
)
[docs] def adjust_paths(self, resources):
"""
Computes relative and absolute paths for resources.
"""
new_resources = []
cdn_base = f'{config.npm_cdn}/@holoviz/panel@{JS_VERSION}/dist/'
for resource in resources:
resource = resource.replace('https://unpkg.com', config.npm_cdn)
if resource.startswith(cdn_base):
resource = resource.replace(cdn_base, CDN_DIST)
if self.mode == 'server':
resource = resource.replace(CDN_DIST, LOCAL_DIST)
if (resource.startswith(state.base_url) or resource.startswith('static/')):
if resource.startswith(state.base_url):
resource = resource[len(state.base_url):]
if state.rel_path:
resource = f'{state.rel_path}/{resource}'
elif self.absolute and self.mode == 'server':
resource = f'{self.root_url}{resource}'
new_resources.append(resource)
return new_resources
[docs] def clone(self, *, components=None) -> Resources:
"""
Make a clone of a resources instance allowing to override its components.
"""
return Resources(
mode=self.mode,
version=self.version,
root_dir=self.root_dir,
dev=self.dev,
minified=self.minified,
log_level=self.log_level,
root_url=self._root_url,
path_versioner=self.path_versioner,
components=components if components is not None else list(self.components),
base_dir=self.base_dir,
notebook=self.notebook,
absolute=self.absolute
)
@property
def dist_dir(self):
if self.notebook and self.mode == 'server':
dist_dir = '/panel-preview/static/extensions/panel/'
elif self.mode == 'server':
if state.rel_path:
dist_dir = f'{state.rel_path}/{LOCAL_DIST}'
else:
dist_dir = LOCAL_DIST
if self.absolute:
dist_dir = f'{self.root_url}{dist_dir}'
else:
dist_dir = CDN_DIST
return dist_dir
@property
def css_files(self):
from ..config import config
files = super(Resources, self).css_files
self.extra_resources(files, '__css__')
css_files = self.adjust_paths([
css for css in files if self.mode != 'inline' or not is_cdn_url(css)
])
if config.design:
css_files += list(config.design._resources.get('font', {}).values())
for cssf in config.css_files:
if os.path.isfile(cssf) or cssf in files:
continue
css_files.append(cssf)
return css_files
@property
def css_raw(self):
from ..config import config
raw = super(Resources, self).css_raw
# Inline local dist resources
css_files = self._collect_external_resources("__css__")
self.extra_resources(css_files, '__css__')
raw += [
(DIST_DIR / css.replace(CDN_DIST, '')).read_text(encoding='utf-8')
for css in css_files if is_cdn_url(css)
]
# Add local CSS files
for cssf in config.css_files:
if not os.path.isfile(cssf):
continue
css_txt = process_raw_css([Path(cssf).read_text(encoding='utf-8')])[0]
if css_txt not in raw:
raw.append(css_txt)
# Add loading spinner
if config.global_loading_spinner:
loading_base = (DIST_DIR / "css" / "loading.css").read_text(encoding='utf-8')
raw.extend([loading_base, loading_css(
config.loading_spinner, config.loading_color, config.loading_max_height
)])
return raw + process_raw_css(config.raw_css) + process_raw_css(config.global_css)
@property
def js_files(self):
from ..config import config
# Gather JS files
files = super(Resources, self).js_files
self.extra_resources(files, '__javascript__')
files += [js for js in config.js_files.values()]
if config.design:
design_js = config.design().resolve_resources(
cdn=self.notebook or 'auto', include_theme=False
)['js'].values()
files += [res for res in design_js if res not in files]
# Filter and adjust JS file urls
js_files = self.adjust_paths([
js for js in files if self.mode != 'inline' or not is_cdn_url(js)
])
# Load requirejs last to avoid interfering with other libraries
dist_dir = self.dist_dir
require_index = [i for i, jsf in enumerate(js_files) if 'require' in jsf]
if require_index:
requirejs = js_files.pop(require_index[0])
if any('ace' in jsf for jsf in js_files):
js_files.append(dist_dir + 'pre_require.js')
js_files.append(requirejs)
if any('ace' in jsf for jsf in js_files):
js_files.append(dist_dir + 'post_require.js')
return js_files
@property
def js_modules(self):
from ..config import config
from ..reactive import ReactiveHTML
modules = list(config.js_modules.values())
self.extra_resources(modules, '__javascript_modules__')
if config.design:
design_resources = config.design().resolve_resources(
cdn=self.notebook or 'auto', include_theme=False
)
modules += [
res for res in design_resources['js_modules'].values()
if res not in modules
]
for model in param.concrete_descendents(ReactiveHTML).values():
if not (getattr(model, '__javascript_modules__', None) and model._loaded()):
continue
for js_module in model.__javascript_modules__:
if not isurl(js_module) and not js_module.startswith('static/extensions'):
js_module = component_resource_path(model, '__javascript_modules__', js_module)
if js_module not in modules:
modules.append(js_module)
return self.adjust_paths(modules)
@property
def js_module_exports(self):
modules = {}
for model in Model.model_class_reverse_map.values():
if hasattr(model, '__javascript_module_exports__'):
modules.update(dict(zip(model.__javascript_module_exports__, model.__javascript_modules__)))
return modules
@property
def js_raw(self):
raw_js = super(Resources, self).js_raw
if not self.mode == 'inline':
return raw_js
# Inline local dist resources
js_files = self._collect_external_resources("__javascript__")
self.extra_resources(js_files, '__javascript__')
raw_js += [
(DIST_DIR / js.replace(CDN_DIST, '')).read_text(encoding='utf-8')
for js in js_files if is_cdn_url(js)
]
# Inline config.js_files
from ..config import config
raw_js += [
Path(js).read_text(encoding='utf-8') for js in config.js_files.values()
if os.path.isfile(js)
]
# Inline config.design JS resources
if config.design:
design_js = config.design().resolve_resources(
cdn=True, include_theme=False
)['js'].values()
raw_js += [
(DIST_DIR / js.replace(CDN_DIST, '')).read_text(encoding='utf-8')
for js in design_js if is_cdn_url(js)
]
return raw_js
@property
def render_js(self):
return JS_RESOURCES.render(
js_raw=self.js_raw, js_files=self.js_files,
js_modules=self.js_modules, hashes=self.hashes,
js_module_exports=self.js_module_exports
)
class Bundle(BkBundle):
def __init__(self, notebook=False, **kwargs):
self.js_modules = kwargs.pop("js_modules", [])
self.js_module_exports = kwargs.pop("js_module_exports", {})
self.notebook = notebook
super().__init__(**kwargs)
@classmethod
def from_bokeh(cls, bk_bundle, notebook=False):
return cls(
notebook=notebook,
js_files=bk_bundle.js_files,
js_raw=bk_bundle.js_raw,
css_files=bk_bundle.css_files,
css_raw=bk_bundle.css_raw,
hashes=bk_bundle.hashes,
)
def _render_css(self) -> str:
return BkCSS_RESOURCES.render(
css_files=self.css_files,
css_raw=self.css_raw
)
def _render_js(self):
return JS_RESOURCES.render(
js_raw=self.js_raw,
js_files=self.js_files,
js_modules=self.js_modules,
js_module_exports=self.js_module_exports,
hashes=self.hashes
)
