Source code for panel.io.resources

"""
Patches bokeh resources to make it easy to add external JS and CSS
resources via the panel.config object.
"""
from __future__ import annotations

import functools
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. ''' internal_path = pathlib.Path(__file__).parent / '..' / '_templates' template_path = pathlib.Path(__file__).parent / '..' / 'template' return Environment(loader=FileSystemLoader([ str(internal_path.resolve()), str(template_path.resolve()) ]))
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 @functools.cache def parse_template(*args, **kwargs): return _env.from_string(*args, **kwargs) # 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') LOGOUT_TEMPLATE = _env.get_template('logout.html') BASIC_LOGIN_TEMPLATE = _env.get_template('basic_login.html') DEFAULT_TITLE = "Panel Application" JS_RESOURCES = _env.get_template('js_resources.html') CDN_ROOT = "https://cdn.holoviz.org/panel/" CDN_URL = f"{CDN_ROOT}{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(r'\.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 try: if not abs_path.is_file(): return None except OSError: 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) + f'?v={JS_VERSION}' elif url.startswith(CDN_DIST) and dist_url != CDN_DIST: patched_url = url.replace(CDN_DIST, dist_url) + f'?v={JS_VERSION}' 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 is not None and 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, '', 1) if state.rel_path: server_url = f'{state.rel_path}/{server_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 extra_resources(self, resources, resource_type): """ Adds resources for ReactiveHTML components. """ from ..reactive import ReactiveHTML for model in param.concrete_descendents(ReactiveHTML).values(): if not (getattr(model, resource_type, None) and model._loaded()): continue for resource in getattr(model, resource_type, []): if not isurl(resource) and not resource.startswith('static/extensions'): resource = component_resource_path(model, resource_type, resource) if resource not in resources: resources.append(resource)
[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, "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__') if self.mode.lower() != 'cdn': 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 )