Source code for panel.io.server

"""
Utilities for creating bokeh Server instances.
"""
from __future__ import annotations

import asyncio
import datetime as dt
import gc
import html
import importlib
import inspect
import logging
import os
import pathlib
import signal
import sys
import threading
import traceback
import uuid
import weakref

from collections import OrderedDict
from contextlib import contextmanager
from functools import partial, wraps
from html import escape
from types import FunctionType, MethodType
from typing import (
    TYPE_CHECKING, Any, Callable, Dict, Mapping, Optional, Union,
)
from urllib.parse import urljoin, urlparse

import bokeh
import bokeh.command.util
import param
import tornado

# Bokeh imports
from bokeh.application import Application as BkApplication
from bokeh.application.handlers.code import (
    CodeHandler, _monkeypatch_io, patch_curdoc,
)
from bokeh.application.handlers.function import FunctionHandler
from bokeh.core.json_encoder import serialize_json
from bokeh.core.templates import AUTOLOAD_JS, FILE, MACROS
from bokeh.core.validation import silence
from bokeh.core.validation.warnings import EMPTY_LAYOUT
from bokeh.embed.bundle import Script
from bokeh.embed.elements import script_for_render_items
from bokeh.embed.util import RenderItem
from bokeh.embed.wrappers import wrap_in_script_tag
from bokeh.io import curdoc
from bokeh.models import CustomJS
from bokeh.server.server import Server as BokehServer
from bokeh.server.urls import per_app_patterns, toplevel_patterns
from bokeh.server.views.autoload_js_handler import (
    AutoloadJsHandler as BkAutoloadJsHandler,
)
from bokeh.server.views.doc_handler import DocHandler as BkDocHandler
from bokeh.server.views.root_handler import RootHandler as BkRootHandler
from bokeh.server.views.static_handler import StaticHandler
from bokeh.util.serialization import make_id
from bokeh.util.token import (
    generate_jwt_token, generate_session_id, get_token_payload,
)
# Tornado imports
from tornado.ioloop import IOLoop
from tornado.web import (
    HTTPError, RequestHandler, StaticFileHandler, authenticated,
)
from tornado.wsgi import WSGIContainer

# Internal imports
from ..config import config
from ..util import edit_readonly, fullpath
from ..util.warnings import warn
from .document import init_doc, unlocked, with_lock  # noqa
from .liveness import LivenessHandler
from .loading import LOADING_INDICATOR_CSS_CLASS
from .logging import (
    LOG_SESSION_CREATED, LOG_SESSION_DESTROYED, LOG_SESSION_LAUNCHING,
)
from .markdown import build_single_handler_application
from .profile import profile_ctx
from .reload import autoreload_watcher
from .resources import (
    BASE_TEMPLATE, CDN_DIST, COMPONENT_PATH, ERROR_TEMPLATE, LOCAL_DIST,
    Resources, _env, bundle_resources, patch_model_css, resolve_custom_path,
)
from .session import generate_session
from .state import set_curdoc, state

logger = logging.getLogger(__name__)

if TYPE_CHECKING:
    from bokeh.bundle import Bundle
    from bokeh.core.types import ID
    from bokeh.document.document import DocJson, Document
    from bokeh.server.contexts import BokehSessionContext
    from bokeh.server.session import ServerSession
    from jinja2 import Template

    from ..template.base import BaseTemplate
    from ..viewable import Viewable, Viewer
    from .location import Location

    TViewable = Union[Viewable, Viewer, BaseTemplate]
    TViewableFuncOrPath = Union[TViewable, Callable[[], TViewable], os.PathLike, str]

#---------------------------------------------------------------------
# Private API
#---------------------------------------------------------------------

INDEX_HTML = os.path.join(os.path.dirname(__file__), '..', '_templates', "index.html")
DEFAULT_TITLE = "Panel Application"

def _origin_url(url: str) -> str:
    if url.startswith("http"):
        url = url.split("//")[1]
    return url

def _server_url(url: str, port: int) -> str:
    if url.startswith("http"):
        return '%s:%d%s' % (url.rsplit(':', 1)[0], port, "/")
    else:
        return 'http://%s:%d%s' % (url.split(':')[0], port, "/")

def _eval_panel(
    panel: TViewableFuncOrPath, server_id: str, title: str,
    location: bool | Location, admin: bool, doc: Document
):
    from ..pane import panel as as_panel
    from ..template import BaseTemplate

    if config.global_loading_spinner:
        doc.js_on_event(
            'document_ready', CustomJS(code=f"""
            const body = document.getElementsByTagName('body')[0]
            body.classList.remove({LOADING_INDICATOR_CSS_CLASS!r}, {config.loading_spinner!r})
            """)
        )

    # Set up instrumentation for logging sessions
    logger.info(LOG_SESSION_LAUNCHING, id(doc))
    def _log_session_destroyed(session_context):
        logger.info(LOG_SESSION_DESTROYED, id(doc))
    doc.on_session_destroyed(_log_session_destroyed)

    with set_curdoc(doc):
        if isinstance(panel, (FunctionType, MethodType)):
            panel = panel()
        if isinstance(panel, BaseTemplate):
            doc = panel._modify_doc(server_id, title, doc, location)
        else:
            doc = as_panel(panel)._modify_doc(server_id, title, doc, location)
        return doc

[docs]def async_execute(func: Callable[..., None]) -> None: """ Wrap async event loop scheduling to ensure that with_lock flag is propagated from function to partial wrapping it. """ if not state.curdoc or not state.curdoc.session_context: ioloop = IOLoop.current() event_loop = ioloop.asyncio_loop # type: ignore wrapper = state._handle_exception_wrapper(func) if event_loop.is_running(): ioloop.add_callback(wrapper) else: event_loop.run_until_complete(wrapper()) return if isinstance(func, partial) and hasattr(func.func, 'lock'): unlock = not func.func.lock # type: ignore else: unlock = not getattr(func, 'lock', False) curdoc = state.curdoc @wraps(func) async def wrapper(*args, **kw): with set_curdoc(curdoc): try: return await func(*args, **kw) except Exception as e: state._handle_exception(e) if unlock: wrapper.nolock = True # type: ignore state.curdoc.add_next_tick_callback(wrapper)
param.parameterized.async_executor = async_execute def _initialize_session_info(session_context: 'BokehSessionContext'): from ..config import config session_id = session_context.id sessions = state.session_info['sessions'] history = -1 if config._admin else config.session_history if not config._admin and (history == 0 or session_id in sessions): return state.session_info['total'] += 1 if history > 0 and len(sessions) >= history: old_history = list(sessions.items()) sessions = OrderedDict(old_history[-(history-1):]) state.session_info['sessions'] = sessions sessions[session_id] = { 'launched': dt.datetime.now().timestamp(), 'started': None, 'rendered': None, 'ended': None, 'user_agent': session_context.request.headers.get('User-Agent') } state.param.trigger('session_info') state._on_session_created_internal.append(_initialize_session_info) #--------------------------------------------------------------------- # Bokeh patches #---------------------------------------------------------------------
[docs]def html_page_for_render_items( bundle: Bundle | tuple[str, str], docs_json: dict[ID, DocJson], render_items: list[RenderItem], title: str, template: Template | str | None = None, template_variables: dict[str, Any] = {} ) -> str: """ Render an HTML page from a template and Bokeh render items. Arguments --------- bundle (tuple): A tuple containing (bokehjs, bokehcss) docs_json (JSON-like): Serialized Bokeh Document render_items (RenderItems) Specific items to render from the document and where title (str or None) A title for the HTML page. If None, DEFAULT_TITLE is used template (str or Template or None, optional) : A Template to be used for the HTML page. If None, FILE is used. template_variables (dict, optional): Any Additional variables to pass to the template Returns ------- str """ if title is None: title = DEFAULT_TITLE bokeh_js, bokeh_css = bundle json_id = make_id() json = escape(serialize_json(docs_json), quote=False) json = wrap_in_script_tag(json, "application/json", json_id) script = wrap_in_script_tag(script_for_render_items(json_id, render_items)) context = template_variables.copy() context.update(dict( title = title, bokeh_js = bokeh_js, bokeh_css = bokeh_css, plot_script = json + script, docs = render_items, base = BASE_TEMPLATE, macros = MACROS, )) if len(render_items) == 1: context["doc"] = context["docs"][0] context["roots"] = context["doc"].roots if template is None: template = BASE_TEMPLATE elif isinstance(template, str): template = _env.from_string("{% extends base %}\n" + template) html = template.render(context) return html
def server_html_page_for_session( session: 'ServerSession', resources: 'Resources', title: str, token: str | None = None, template: str | Template = BASE_TEMPLATE, template_variables: Optional[Dict[str, Any]] = None, ) -> str: # ALERT: Replace with better approach before Bokeh 3.x compatible release if resources.mode == 'server': dist_url = f'{state.rel_path}/{LOCAL_DIST}' if state.rel_path else LOCAL_DIST else: dist_url = CDN_DIST doc = session.document doc._template_variables['theme_name'] = config.theme doc._template_variables['dist_url'] = dist_url for root in doc.roots: patch_model_css(root, dist_url=dist_url) render_item = RenderItem( token = token or session.token, roots = doc.roots, use_for_title = False, ) if template_variables is None: template_variables = {} if template is FILE: template = BASE_TEMPLATE with set_curdoc(doc): bundle = bundle_resources(doc.roots, resources) html = html_page_for_render_items( bundle, {}, [render_item], title, template=template, template_variables=template_variables ) if config.global_loading_spinner: html = html.replace( '<body>', f'<body class="{LOADING_INDICATOR_CSS_CLASS} pn-{config.loading_spinner}">' ) return html def autoload_js_script(doc, resources, token, element_id, app_path, absolute_url, absolute=False): resources = Resources.from_bokeh(resources, absolute=absolute) bundle = bundle_resources(doc.roots, resources) render_items = [RenderItem(token=token, elementid=element_id, use_for_title=False)] bundle.add(Script(script_for_render_items({}, render_items, app_path=app_path, absolute_url=absolute_url))) return AUTOLOAD_JS.render(bundle=bundle, elementid=element_id)
[docs]def destroy_document(self, session): """ Override for Document.destroy() without calling gc.collect directly. The gc.collect() call is scheduled as a task, ensuring that when multiple documents are destroyed in quick succession we do not schedule excessive garbage collection. """ if session is not None: self.remove_on_change(session) del self._roots del self._theme del self._template self._session_context = None self.callbacks.destroy() self.models.destroy() self.modules.destroy() # Clear periodic callbacks for cb in state._periodic.get(self, []): cb.stop() # Clean up pn.state to avoid tasks getting executed on dead session for attr in dir(state): # _param_watchers is deprecated in Param 2.0 and will raise a warning if not attr.startswith('_') or attr == "_param_watchers": continue state_obj = getattr(state, attr) if isinstance(state_obj, weakref.WeakKeyDictionary) and self in state_obj: del state_obj[self] # Schedule GC at = dt.datetime.now() + dt.timedelta(seconds=5) state.schedule_task('gc.collect', gc.collect, at=at) del self.destroy
# Patch Server to attach task factory to asyncio loop and handle Admin server context
[docs]class Server(BokehServer): def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) if state._admin_context: state._admin_context._loop = self._loop
[docs] def start(self) -> None: super().start() if state._admin_context: self._loop.add_callback(state._admin_context.run_load_hook)
[docs] def stop(self, wait: bool = True) -> None: super().stop(wait=wait) if state._admin_context: state._admin_context.run_unload_hook()
bokeh.server.server.Server = Server # Patch Application to handle session callbacks
[docs]class Application(BkApplication): def __init__(self, *args, **kwargs): self._admin = kwargs.pop('admin', None) super().__init__(*args, **kwargs)
[docs] async def on_session_created(self, session_context): with set_curdoc(session_context._document): if self._admin is not None: config._admin = self._admin for cb in state._on_session_created_internal+state._on_session_created: cb(session_context) await super().on_session_created(session_context)
[docs] def initialize_document(self, doc): super().initialize_document(doc) if doc in state._templates and doc not in state._templates[doc]._documents: template = state._templates[doc] with set_curdoc(doc): template.server_doc(title=template.title, location=True, doc=doc)
bokeh.command.util.Application = Application # type: ignore class SessionPrefixHandler: @contextmanager def _session_prefix(self): prefix = self.request.uri.replace(self.application_context._url, '') if not prefix.endswith('/'): prefix += '/' base_url = urljoin('/', prefix) rel_path = '/'.join(['..'] * self.application_context._url.strip('/').count('/')) old_url, old_rel = state.base_url, state.rel_path # Handle autoload.js absolute paths abs_url = self.get_argument('bokeh-absolute-url', default=None) if abs_url is not None: rel_path = abs_url.replace(self.application_context._url, '') with edit_readonly(state): state.base_url = base_url state.rel_path = rel_path try: yield finally: with edit_readonly(state): state.base_url = old_url state.rel_path = old_rel
[docs]class LoginUrlMixin: """ Overrides the AuthRequestHandler.get_login_url implementation to correctly handle prefixes. """
[docs] def get_login_url(self): ''' Delegates to``get_login_url`` method of the auth provider, or the ``login_url`` attribute. ''' if self.application.auth_provider.get_login_url is not None: return '.' + self.application.auth_provider.get_login_url(self) if self.application.auth_provider.login_url is not None: return '.' + self.application.auth_provider.login_url raise RuntimeError('login_url or get_login_url() must be supplied when authentication hooks are enabled')
# Patch Bokeh DocHandler URL
[docs]class DocHandler(LoginUrlMixin, BkDocHandler, SessionPrefixHandler): @authenticated async def get_session(self): from ..config import config path = self.request.path session = None if config.reuse_sessions and path in state._session_key_funcs: key = state._session_key_funcs[path](self.request) session = state._sessions.get(key) if session is None: session = await super().get_session() with set_curdoc(session.document): if config.reuse_sessions: key_func = config.session_key_func or (lambda r: (r.path, r.arguments.get('theme', [b'default'])[0].decode('utf-8'))) state._session_key_funcs[path] = key_func key = key_func(self.request) state._sessions[key] = session session.block_expiration() return session def _generate_token_payload(self): app = self.application if app.include_headers is None: excluded_headers = (app.exclude_headers or []) allowed_headers = [header for header in self.request.headers if header not in excluded_headers] else: allowed_headers = app.include_headers headers = {k: v for k, v in self.request.headers.items() if k in allowed_headers} if app.include_cookies is None: excluded_cookies = (app.exclude_cookies or []) allowed_cookies = [cookie for cookie in self.request.cookies if cookie not in excluded_cookies] else: allowed_cookies = app.include_cookies cookies = {k: v.value for k, v in self.request.cookies.items() if k in allowed_cookies} if cookies and 'Cookie' in headers and 'Cookie' not in (app.include_headers or []): # Do not include Cookie header since cookies can be restored from cookies dict del headers['Cookie'] arguments = {} if self.request.arguments is None else self.request.arguments payload = {'headers': headers, 'cookies': cookies, 'arguments': arguments} payload.update(self.application_context.application.process_request(self.request)) return payload def _authorize(self, session=False): """ """ auth_cb = config.authorize_callback # If inside a session ensure the authorize callback is not global if not auth_cb or (session and auth_cb is config._param__private.values['authorize_callback']): return True, None authorized = False auth_params = inspect.signature(auth_cb).parameters if len(auth_params) == 1: auth_args = (state.user_info,) elif len(auth_params) == 2: auth_args = (state.user_info, self.request.path,) else: raise RuntimeError( 'Authorization callback must accept either 1) a single argument ' 'which is the user name or 2) two arguments which includes the ' 'user name and the url path the user is trying to access.' ) auth_error = f'{state.user} is not authorized to access this application.' try: authorized = auth_cb(*auth_args) if isinstance(authorized, str): self.redirect(authorized) return None, None elif not authorized: auth_error = ( f'Access denied! User {state.user!r} is not authorized ' f'for the given app {self.request.path!r}.' ) if authorized: auth_error = None except Exception: auth_error = f'Authorization callback errored. Could not validate user {state.user}.' return authorized, auth_error def _render_auth_error(self, auth_error): if config.auth_template: with open(config.auth_template) as f: template = _env.from_string(f.read()) else: template = ERROR_TEMPLATE return template.render( npm_cdn=config.npm_cdn, title='Panel: Authorization Error', error_type='Authorization Error', error='User is not authorized.', error_msg=auth_error ) @authenticated async def get(self, *args, **kwargs): # Run global authorization callback payload = self._generate_token_payload() if config.authorize_callback: temp_session = generate_session( self.application, self.request, payload, initialize=False ) with set_curdoc(temp_session.document): authorized, auth_error = self._authorize() if authorized is None: return elif not authorized: self._render_auth_error(auth_error) page = self.set_header("Content-Type", 'text/html') self.write(page) return app = self.application with self._session_prefix(): key_func = state._session_key_funcs.get(self.request.path, lambda r: r.path) old_request = key_func(self.request) in state._sessions session = await self.get_session() if old_request and state._sessions.get(key_func(self.request)) is session: session_id = generate_session_id( secret_key=self.application.secret_key, signed=self.application.sign_sessions ) payload = get_token_payload(session.token) payload.update(payload) del payload['session_expiry'] token = generate_jwt_token( session_id, secret_key=app.secret_key, signed=app.sign_sessions, expiration=app.session_token_expiration, extra_payload=payload ) else: token = session.token logger.info(LOG_SESSION_CREATED, id(session.document)) with set_curdoc(session.document): resources = Resources.from_bokeh(self.application.resources()) # Session authorization callback authorized, auth_error = self._authorize(session=True) if authorized: page = server_html_page_for_session( session, resources=resources, title=session.document.title, token=token, template=session.document.template, template_variables=session.document.template_variables, ) elif authorized is None: return else: page = self._render_auth_error(auth_error) self.set_header("Content-Type", 'text/html') self.write(page)
per_app_patterns[0] = (r'/?', DocHandler) # Patch Bokeh Autoload handler
[docs]class AutoloadJsHandler(BkAutoloadJsHandler, SessionPrefixHandler): ''' Implements a custom Tornado handler for the autoload JS chunk ''' async def get(self, *args, **kwargs) -> None: element_id = self.get_argument("bokeh-autoload-element", default=None) if not element_id: self.send_error(status_code=400, reason='No bokeh-autoload-element query parameter') return app_path = self.get_argument("bokeh-app-path", default="/") absolute_url = self.get_argument("bokeh-absolute-url", default=None) if absolute_url: server_url = '{uri.scheme}://{uri.netloc}'.format(uri=urlparse(absolute_url)) else: server_url = None with self._session_prefix(): session = await self.get_session() with set_curdoc(session.document): resources = Resources.from_bokeh( self.application.resources(server_url), absolute=True ) js = autoload_js_script( session.document, resources, session.token, element_id, app_path, absolute_url, absolute=True ) self.set_header("Content-Type", 'application/javascript') self.write(js)
per_app_patterns[3] = (r'/autoload.js', AutoloadJsHandler)
[docs]class RootHandler(LoginUrlMixin, BkRootHandler): """ Custom RootHandler that provides the CDN_DIST directory as a template variable. """
[docs] def render(self, *args, **kwargs): kwargs['PANEL_CDN'] = CDN_DIST return super().render(*args, **kwargs)
toplevel_patterns[0] = (r'/?', RootHandler) bokeh.server.tornado.RootHandler = RootHandler
[docs]class ComponentResourceHandler(StaticFileHandler): """ A handler that serves local resources relative to a Python module. The handler resolves a specific Panel component by module reference and name, then resolves an attribute on that component to check if it contains the requested resource path. /<endpoint>/<module>/<class>/<attribute>/<path> """ _resource_attrs = [ '__css__', '__javascript__', '__js_module__', '__javascript_modules__', '_resources', '_css', '_js', 'base_css', 'css', '_stylesheets', 'modifiers' ]
[docs] def initialize(self, path: Optional[str] = None, default_filename: Optional[str] = None): self.root = path self.default_filename = default_filename
[docs] def parse_url_path(self, path: str) -> str: """ Resolves the resource the URL pattern refers to. """ parts = path.split('/') if len(parts) < 4: raise HTTPError(400, 'Malformed URL') mod, cls, rtype, *subpath = parts try: module = importlib.import_module(mod) except ModuleNotFoundError: raise HTTPError(404, 'Module not found') try: component = getattr(module, cls) except AttributeError: raise HTTPError(404, 'Component not found') # May only access resources listed in specific attributes if rtype not in self._resource_attrs: raise HTTPError(403, 'Requested resource type not valid.') try: resources = getattr(component, rtype) except AttributeError: raise HTTPError(404, 'Resource type not found') # Handle template resources if rtype == '_resources': rtype = subpath[0] subpath = subpath[1:] if rtype not in resources: raise HTTPError(404, 'Resource type not found') resources = resources[rtype] rtype = f'_resources/{rtype}' elif rtype == 'modifiers': resources = [ st for rs in resources.values() for st in rs.get('stylesheets', []) if isinstance(st, str) ] if isinstance(resources, dict): resources = list(resources.values()) elif isinstance(resources, (str, pathlib.PurePath)): resources = [resources] resources = [ str(resolve_custom_path(component, resource, relative=True)).replace(os.path.sep, '/') for resource in resources ] rel_path = '/'.join(subpath) # Important: May only access resources explicitly listed on the component # Otherwise this potentially exposes all files to the web if rel_path not in resources: raise HTTPError(403, 'Requested resource was not listed.') if not module.__file__: raise HTTPError(404, 'Requested module does not reference a file.') return str(pathlib.Path(module.__file__).parent / rel_path)
[docs] @classmethod def get_absolute_path(cls, root: str, path: str) -> str: return path
[docs] def validate_absolute_path(self, root: str, absolute_path: str) -> str: if not os.path.exists(absolute_path): raise HTTPError(404) if not os.path.isfile(absolute_path): raise HTTPError(403, "%s is not a file", self.path) return absolute_path
def modify_document(self, doc: 'Document'): from bokeh.io.doc import set_curdoc as bk_set_curdoc from ..config import config logger.info(LOG_SESSION_LAUNCHING, id(doc)) if config.autoreload: path = self._runner.path argv = self._runner._argv handler = type(self)(filename=path, argv=argv) self._runner = handler._runner module = self._runner.new_module() # If no module was returned it means the code runner has some permanent # unfixable problem, e.g. the configured source code has a syntax error if module is None: return # One reason modules are stored is to prevent the module # from being gc'd before the document is. A symptom of a # gc'd module is that its globals become None. Additionally # stored modules are used to provide correct paths to # custom models resolver. sys.modules[module.__name__] = module doc.modules._modules.append(module) try: old_doc = curdoc() except RuntimeError: old_doc = None bk_set_curdoc(doc) if config.autoreload: set_curdoc(doc) state.onload(autoreload_watcher) sessions = [] try: def post_check(): newdoc = curdoc() # Do not let curdoc track modules when autoreload is enabled # otherwise it will erroneously complain that there is # a memory leak if config.autoreload: newdoc.modules._modules = [] # script is supposed to edit the doc not replace it if newdoc is not doc: raise RuntimeError("%s at '%s' replaced the output document" % (self._origin, self._runner.path)) def handle_exception(handler, e): from bokeh.application.handlers.handler import handle_exception from ..pane import Alert # Clean up del sys.modules[module.__name__] if hasattr(doc, 'modules'): doc.modules._modules.remove(module) else: doc._modules.remove(module) bokeh.application.handlers.code_runner.handle_exception = handle_exception tb = html.escape(traceback.format_exc()).replace('\033[1m', '<b>').replace('\033[0m', '</b>') # Serve error e_msg = str(e).replace('\033[1m', '<b>').replace('\033[0m', '</b>') Alert( f'<b>{type(e).__name__}</b>: {e_msg}\n<pre style="overflow-y: auto">{tb}</pre>', alert_type='danger', margin=5, sizing_mode='stretch_width' ).servable() if config.autoreload: bokeh.application.handlers.code_runner.handle_exception = handle_exception state._launching.append(doc) with _monkeypatch_io(self._loggers): with patch_curdoc(doc): with profile_ctx(config.profiler) as sessions: self._runner.run(module, post_check) def _log_session_destroyed(session_context): logger.info(LOG_SESSION_DESTROYED, id(doc)) doc.on_session_destroyed(_log_session_destroyed) doc.destroy = partial(destroy_document, doc) # type: ignore finally: state._launching.remove(doc) if config.profiler: try: path = doc.session_context.request.path state._profiles[(path, config.profiler)] += sessions state.param.trigger('_profiles') except Exception: pass if old_doc is not None: bk_set_curdoc(old_doc) CodeHandler.modify_document = modify_document # type: ignore # Copied from bokeh 2.4.0, to fix directly in bokeh at some point. def create_static_handler(prefix, key, app): # patch key = '/__patchedroot' if key == '/' else key route = prefix route += "/static/(.*)" if key == "/" else key + "/static/(.*)" if app.static_path is not None: return (route, StaticFileHandler, {"path" : app.static_path}) return (route, StaticHandler, {}) bokeh.server.tornado.create_static_handler = create_static_handler #--------------------------------------------------------------------- # Async patches #--------------------------------------------------------------------- # Bokeh 2.4.x patches the asyncio event loop policy but Tornado 6.1 # support the WindowsProactorEventLoopPolicy so we restore it, # unless we detect we are running on jupyter_server. if ( sys.platform == 'win32' and sys.version_info[:3] >= (3, 8, 0) and tornado.version_info >= (6, 1) and type(asyncio.get_event_loop_policy()) is asyncio.WindowsSelectorEventLoopPolicy and (('jupyter_server' not in sys.modules and 'jupyter_client' not in sys.modules) or 'pytest' in sys.modules) ): asyncio.set_event_loop_policy(asyncio.WindowsProactorEventLoopPolicy()) #--------------------------------------------------------------------- # Public API #---------------------------------------------------------------------
[docs]def serve( panels: TViewableFuncOrPath | Mapping[str, TViewableFuncOrPath], port: int = 0, address: Optional[str] = None, websocket_origin: Optional[str | list[str]] = None, loop: Optional[IOLoop] = None, show: bool = True, start: bool = True, title: Optional[str] = None, verbose: bool = True, location: bool = True, threaded: bool = False, admin: bool = False, **kwargs ) -> StoppableThread | Server: """ Allows serving one or more panel objects on a single server. The panels argument should be either a Panel object or a function returning a Panel object or a dictionary of these two. If a dictionary is supplied the keys represent the slugs at which each app is served, e.g. `serve({'app': panel1, 'app2': panel2})` will serve apps at /app and /app2 on the server. Reference: https://panel.holoviz.org/user_guide/Server_Configuration.html#serving-multiple-apps Arguments --------- panel: Viewable, function or {str: Viewable or function} A Panel object, a function returning a Panel object or a dictionary mapping from the URL slug to either. 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. loop : tornado.ioloop.IOLoop (optional, default=IOLoop.current()) The tornado IOLoop to run the Server on show : boolean (optional, default=True) Whether to open the server in a new browser tab on start start : boolean(optional, default=True) Whether to start the Server title: str or {str: str} (optional, default=None) An HTML title for the application or a dictionary mapping from the URL slug to a customized title verbose: boolean (optional, default=True) Whether to print the address and port location : boolean or panel.io.location.Location Whether to create a Location component to observe and set the URL location. threaded: boolean (default=False) Whether to start the server on a new Thread admin: boolean (default=False) Whether to enable the admin panel kwargs: dict Additional keyword arguments to pass to Server instance """ # Empty layout are valid and the Bokeh warning is silenced as usually # not relevant to Panel users. silence(EMPTY_LAYOUT, True) kwargs = dict(kwargs, **dict( port=port, address=address, websocket_origin=websocket_origin, loop=loop, show=show, start=start, title=title, verbose=verbose, location=location, admin=admin )) if threaded: kwargs['loop'] = loop = IOLoop(make_current=False) if loop is None else loop server = StoppableThread( target=get_server, io_loop=loop, args=(panels,), kwargs=kwargs ) server_id = kwargs.get('server_id', uuid.uuid4().hex) state._threads[server_id] = server server.start() else: return get_server(panels, **kwargs) return server
[docs]class ProxyFallbackHandler(RequestHandler): """A `RequestHandler` that wraps another HTTP server callback and proxies the subpath. """
[docs] def initialize(self, fallback, proxy=None): self.fallback = fallback self.proxy = proxy
[docs] def prepare(self): if self.proxy: self.request.path = self.request.path.replace(self.proxy, '') self.fallback(self.request) self._finished = True self.on_finish()
[docs]def get_static_routes(static_dirs): """ Returns a list of tornado routes of StaticFileHandlers given a dictionary of slugs and file paths to serve. """ patterns = [] for slug, path in static_dirs.items(): if not slug.startswith('/'): slug = '/' + slug if slug == '/static': raise ValueError("Static file route may not use /static " "this is reserved for internal use.") path = fullpath(path) if not os.path.isdir(path): raise ValueError("Cannot serve non-existent path %s" % path) patterns.append( (r"%s/(.*)" % slug, StaticFileHandler, {"path": path}) ) patterns.append(( f'/{COMPONENT_PATH}(.*)', ComponentResourceHandler, {} )) return patterns
[docs]def get_server( panel: TViewableFuncOrPath | Mapping[str, TViewableFuncOrPath], port: int = 0, address: Optional[str] = None, websocket_origin: Optional[str | list[str]] = None, loop: Optional[IOLoop] = None, show: bool = False, start: bool = False, title: bool = None, verbose: bool = False, location: bool | Location = True, admin: bool = False, static_dirs: Mapping[str, str] = {}, basic_auth: str = None, oauth_provider: Optional[str] = None, oauth_key: Optional[str] = None, oauth_secret: Optional[str] = None, oauth_redirect_uri: Optional[str] = None, oauth_extra_params: Mapping[str, str] = {}, oauth_error_template: Optional[str] = None, cookie_secret: Optional[str] = None, oauth_encryption_key: Optional[str] = None, oauth_jwt_user: Optional[str] = None, oauth_refresh_tokens: Optional[bool] = None, oauth_guest_endpoints: Optional[bool] = None, oauth_optional: Optional[bool] = None, login_endpoint: Optional[str] = None, logout_endpoint: Optional[str] = None, login_template: Optional[str] = None, logout_template: Optional[str] = None, session_history: Optional[int] = None, liveness: bool | str = False, **kwargs ) -> Server: """ Returns a Server instance with this panel attached as the root app. Arguments --------- panel: Viewable, function or {str: Viewable} A Panel object, a function returning a Panel object or a dictionary mapping from the URL slug to either. 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. loop : tornado.ioloop.IOLoop (optional, default=IOLoop.current()) The tornado IOLoop to run the Server on. show : boolean (optional, default=False) Whether to open the server in a new browser tab on start. start : boolean(optional, default=False) Whether to start the Server. title : str or {str: str} (optional, default=None) An HTML title for the application or a dictionary mapping from the URL slug to a customized title. verbose: boolean (optional, default=False) Whether to report the address and port. location : boolean or panel.io.location.Location Whether to create a Location component to observe and set the URL location. admin: boolean (default=False) Whether to enable the admin panel static_dirs: dict (optional, default={}) A dictionary of routes and local paths to serve as static file directories on those routes. basic_auth: str (optional, default=None) Password or filepath to use with basic auth provider. oauth_provider: str One of the available OAuth providers oauth_key: str (optional, default=None) The public OAuth identifier oauth_secret: str (optional, default=None) The client secret for the OAuth provider oauth_redirect_uri: Optional[str] = None, Overrides the default OAuth redirect URI oauth_jwt_user: Optional[str] = None, Key that identifies the user in the JWT id_token. oauth_extra_params: dict (optional, default={}) Additional information for the OAuth provider oauth_error_template: str (optional, default=None) Jinja2 template used when displaying authentication errors. cookie_secret: str (optional, default=None) A random secret string to sign cookies (required for OAuth) oauth_encryption_key: str (optional, default=None) A random encryption key used for encrypting OAuth user information and access tokens. oauth_guest_endpoints: list (optional, default=None) List of endpoints that can be accessed as a guest without authenticating. oauth_optional: bool (optional, default=None) Whether the user will be forced to go through login flow or if they can access all applications as a guest. oauth_refresh_tokens: bool (optional, default=None) Whether to automatically refresh OAuth access tokens when they expire. login_endpoint: str (optional, default=None) Overrides the default login endpoint `/login` logout_endpoint: str (optional, default=None) Overrides the default logout endpoint `/logout` logout_template: str (optional, default=None) Jinja2 template served when viewing the login endpoint when authentication is enabled. logout_template: str (optional, default=None) Jinja2 template served when viewing the logout endpoint when authentication is enabled. session_history: int (optional, default=None) The amount of session history to accumulate. If set to non-zero and non-None value will launch a REST endpoint at /rest/session_info, which returns information about the session history. liveness: bool | str (optional, default=False) Whether to add a liveness endpoint. If a string is provided then this will be used as the endpoint, otherwise the endpoint will be hosted at /liveness. kwargs: dict Additional keyword arguments to pass to Server instance. Returns ------- server : panel.io.server.Server Bokeh Server instance running this panel """ from ..config import config from .rest import REST_PROVIDERS server_id = kwargs.pop('server_id', uuid.uuid4().hex) kwargs['extra_patterns'] = extra_patterns = kwargs.get('extra_patterns', []) if isinstance(panel, dict): apps = {} for slug, app in panel.items(): if slug.endswith('/') and not slug == '/': raise ValueError(f"Invalid URL: trailing slash '/' used for {slug!r} not supported.") if isinstance(title, dict): try: title_ = title[slug] except KeyError: raise KeyError( "Keys of the title dictionary and of the apps " f"dictionary must match. No {slug} key found in the " "title dictionary.") else: title_ = title slug = slug if slug.startswith('/') else '/'+slug if 'flask' in sys.modules: from flask import Flask if isinstance(app, Flask): wsgi = WSGIContainer(app) if slug == '/': raise ValueError('Flask apps must be served on a subpath.') if not slug.endswith('/'): slug += '/' extra_patterns.append(('^'+slug+'.*', ProxyFallbackHandler, dict(fallback=wsgi, proxy=slug))) continue if isinstance(app, pathlib.Path): app = str(app) # enables serving apps from Paths if (isinstance(app, str) and (app.endswith(".py") or app.endswith(".ipynb") or app.endswith('.md')) and os.path.isfile(app)): apps[slug] = app = build_single_handler_application(app) app._admin = admin elif isinstance(app, BkApplication): apps[slug] = app else: handler = FunctionHandler(partial(_eval_panel, app, server_id, title_, location, admin)) apps[slug] = Application(handler, admin=admin) else: if isinstance(panel, pathlib.Path): panel = str(panel) # enables serving apps from Paths if (isinstance(panel, str) and (panel.endswith(".py") or panel.endswith(".ipynb") or panel.endswith('.md')) and os.path.isfile(panel)): apps = {'/': build_single_handler_application(panel)} else: handler = FunctionHandler(partial(_eval_panel, panel, server_id, title, location, admin)) apps = {'/': Application(handler, admin=admin)} if admin: if '/admin' in apps: raise ValueError( 'Cannot enable admin panel because another app is being served ' 'on the /admin endpoint' ) from .admin import admin_panel admin_handler = FunctionHandler(admin_panel) apps['/admin'] = Application(admin_handler) extra_patterns += get_static_routes(static_dirs) if session_history is not None: config.session_history = session_history if config.session_history != 0: pattern = REST_PROVIDERS['param']([], 'rest') extra_patterns.extend(pattern) state.publish('session_info', state, ['session_info']) if liveness: liveness_endpoint = 'liveness' if isinstance(liveness, bool) else liveness extra_patterns += [(r"/%s" % liveness_endpoint, LivenessHandler, dict(applications=apps))] opts = dict(kwargs) if loop: asyncio.set_event_loop(loop.asyncio_loop) opts['io_loop'] = loop elif opts.get('num_procs', 1) == 1: opts['io_loop'] = IOLoop.current() if 'index' not in opts: opts['index'] = INDEX_HTML if address is not None: opts['address'] = address if websocket_origin: if not isinstance(websocket_origin, list): websocket_origin = [websocket_origin] opts['allow_websocket_origin'] = websocket_origin # Configure OAuth from ..config import config server_config = {} login_template = kwargs.pop('basic_login_template', login_template) if basic_auth or oauth_provider: from ..auth import BasicAuthProvider, OAuthProvider if basic_auth: server_config['basic_auth'] = basic_auth provider = BasicAuthProvider else: config.oauth_provider = oauth_provider provider = OAuthProvider opts['auth_provider'] = provider( login_endpoint=login_endpoint, logout_endpoint=logout_endpoint, login_template=login_template, logout_template=logout_template, error_template=oauth_error_template ) if oauth_key: config.oauth_key = oauth_key # type: ignore if oauth_secret: config.oauth_secret = oauth_secret # type: ignore if oauth_extra_params: config.oauth_extra_params = oauth_extra_params # type: ignore if cookie_secret: config.cookie_secret = cookie_secret # type: ignore if oauth_redirect_uri: config.oauth_redirect_uri = oauth_redirect_uri # type: ignore if oauth_refresh_tokens is not None: config.oauth_refresh_tokens = oauth_refresh_tokens if oauth_optional is not None: config.oauth_optional = oauth_optional if oauth_guest_endpoints is not None: config.oauth_guest_endpoints = oauth_guest_endpoints if oauth_jwt_user is not None: config.oauth_jwt_user = oauth_jwt_user opts['cookie_secret'] = config.cookie_secret server = Server(apps, port=port, **opts) if verbose: address = server.address or 'localhost' url = f"http://{address}:{server.port}{server.prefix}" print(f"Launching server at {url}") state._servers[server_id] = (server, panel, []) state._server_config[server._tornado] = server_config if show: login_endpoint = login_endpoint or '/login' def show_callback(): server.show(login_endpoint if config.oauth_provider or basic_auth else '/') server.io_loop.add_callback(show_callback) def sig_exit(*args, **kwargs): server.io_loop.add_callback_from_signal(do_stop) def do_stop(*args, **kwargs): server.io_loop.stop() try: signal.signal(signal.SIGINT, sig_exit) except ValueError: pass # Can't use signal on a thread if start: server.start() try: server.io_loop.start() except RuntimeError: pass except TypeError: warn( "IOLoop couldn't be started. Ensure it is started by " "process invoking the panel.io.server.serve." ) return server
[docs]class StoppableThread(threading.Thread): """Thread class with a stop() method.""" def __init__(self, io_loop: IOLoop, **kwargs): super().__init__(**kwargs) self.io_loop = io_loop
[docs] def run(self) -> None: if hasattr(self, '_target'): target, args, kwargs = self._target, self._args, self._kwargs # type: ignore else: target, args, kwargs = self._Thread__target, self._Thread__args, self._Thread__kwargs # type: ignore if not target: return bokeh_server = None try: bokeh_server = target(*args, **kwargs) finally: if isinstance(bokeh_server, Server): try: bokeh_server.stop() except Exception: pass if hasattr(self, '_target'): del self._target, self._args, self._kwargs # type: ignore else: del self._Thread__target, self._Thread__args, self._Thread__kwargs # type: ignore
def stop(self) -> None: self.io_loop.add_callback(self.io_loop.stop)