#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2021, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
''' Provides the Bokeh Server Tornado application.
'''
#-----------------------------------------------------------------------------
# Boilerplate
#-----------------------------------------------------------------------------
from __future__ import annotations
import logging # isort:skip
log = logging.getLogger(__name__)
#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------
# Standard library imports
import gc
import os
from pprint import pformat
from types import ModuleType
from typing import (
TYPE_CHECKING,
Any,
Dict,
List,
Mapping,
Sequence,
Set,
Tuple,
)
from urllib.parse import urljoin
# External imports
from tornado.ioloop import PeriodicCallback
from tornado.web import Application as TornadoApplication, StaticFileHandler
if TYPE_CHECKING:
from tornado.ioloop import IOLoop
# Bokeh imports
from ..application import Application
from ..document import Document
from ..model import Model
from ..resources import Resources
from ..settings import settings
from ..util.dependencies import import_optional
from ..util.string import format_docstring
from ..util.tornado import fixup_windows_event_loop_policy
from .auth_provider import NullAuth
from .connection import ServerConnection
from .contexts import ApplicationContext
from .session import ServerSession
from .urls import per_app_patterns, toplevel_patterns
from .views.root_handler import RootHandler
from .views.static_handler import StaticHandler
from .views.ws import WSHandler
if TYPE_CHECKING:
from ..application.handlers.function import ModifyDoc
from ..core.types import ID
from ..protocol import Protocol
from .auth_provider import AuthProvider
from .urls import RouteContext, URLRoutes
#-----------------------------------------------------------------------------
# Globals and constants
#-----------------------------------------------------------------------------
DEFAULT_CHECK_UNUSED_MS = 17000
DEFAULT_KEEP_ALIVE_MS = 37000 # heroku, nginx default to 60s timeout, so use less than that
DEFAULT_MEM_LOG_FREQ_MS = 0
DEFAULT_STATS_LOG_FREQ_MS = 15000
DEFAULT_UNUSED_LIFETIME_MS = 15000
DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES = 20*1024*1024
DEFAULT_SESSION_TOKEN_EXPIRATION = 300
__all__ = (
'BokehTornado',
)
pd = import_optional("pandas")
psutil = import_optional("psutil")
GB = 2**20
PID = os.getpid()
if psutil:
PROC = psutil.Process(PID)
#-----------------------------------------------------------------------------
# General API
#-----------------------------------------------------------------------------
[docs]class BokehTornado(TornadoApplication):
''' A Tornado Application used to implement the Bokeh Server.
Args:
applications (dict[str,Application] or Application) :
A map from paths to ``Application`` instances.
If the value is a single Application, then the following mapping
is generated:
.. code-block:: python
applications = {{ '/' : applications }}
When a connection comes in to a given path, the associate
Application is used to generate a new document for the session.
prefix (str, optional) :
A URL prefix to use for all Bokeh server paths. (default: None)
extra_websocket_origins (list[str], optional) :
A list of hosts that can connect to the websocket.
This is typically required when embedding a Bokeh server app in an
external web site using :func:`~bokeh.embed.server_document` or
similar.
If None, ``["localhost"]`` will be assumed (default: None)
extra_patterns (seq[tuple], optional) :
A list of tuples of (str, http or websocket handler)
Use this argument to add additional endpoints to custom deployments
of the Bokeh Server.
If None, then ``[]`` will be used. (default: None)
secret_key (str, optional) :
A secret key for signing session IDs.
Defaults to the current value of the environment variable
``BOKEH_SECRET_KEY``
sign_sessions (bool, optional) :
Whether to cryptographically sign session IDs
Defaults to the current value of the environment variable
``BOKEH_SIGN_SESSIONS``. If ``True``, then ``secret_key`` must
also be provided (either via environment setting or passed as
a parameter value)
generate_session_ids (bool, optional) :
Whether to generate a session ID if one is not provided
(default: True)
keep_alive_milliseconds (int, optional) :
Number of milliseconds between keep-alive pings
(default: {DEFAULT_KEEP_ALIVE_MS})
Pings normally required to keep the websocket open. Set to 0 to
disable pings.
check_unused_sessions_milliseconds (int, optional) :
Number of milliseconds between checking for unused sessions
(default: {DEFAULT_CHECK_UNUSED_MS})
unused_session_lifetime_milliseconds (int, optional) :
Number of milliseconds for unused session lifetime
(default: {DEFAULT_UNUSED_LIFETIME_MS})
stats_log_frequency_milliseconds (int, optional) :
Number of milliseconds between logging stats
(default: {DEFAULT_STATS_LOG_FREQ_MS})
mem_log_frequency_milliseconds (int, optional) :
Number of milliseconds between logging memory information
(default: {DEFAULT_MEM_LOG_FREQ_MS})
Enabling this feature requires the optional dependency ``psutil`` to be
installed.
use_index (bool, optional) :
Whether to generate an index of running apps in the ``RootHandler``
(default: True)
index (str, optional) :
Path to a Jinja2 template to serve as the index for "/" if use_index
is True. If None, the basic built in app index template is used.
(default: None)
redirect_root (bool, optional) :
When there is only a single running application, whether to
redirect requests to ``"/"`` to that application automatically
(default: True)
If there are multiple Bokeh applications configured, this option
has no effect.
websocket_max_message_size_bytes (int, optional):
Set the Tornado ``websocket_max_message_size`` value.
(default: {DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES})
websocket_compression_level (int, optional):
Set the Tornado WebSocket ``compression_level`` documented in
https://docs.python.org/3.7/library/zlib.html#zlib.compressobj.
websocket_compression_mem_level (int, optional):
Set the Tornado WebSocket compression ``mem_level`` documented in
https://docs.python.org/3.7/library/zlib.html#zlib.compressobj.
index (str, optional):
Path to a Jinja2 template to use for the root URL
auth_provider (AuthProvider, optional):
An AuthProvider instance
include_headers (list, optional) :
List of request headers to include in session context
(by default all headers are included)
exclude_headers (list, optional) :
List of request headers to exclude in session context
(by default all headers are included)
include_cookies (list, optional) :
List of cookies to include in session context
(by default all cookies are included)
exclude_cookies (list, optional) :
List of cookies to exclude in session context
(by default all cookies are included)
session_token_expiration (int, optional) :
Duration in seconds that a new session token is valid
for session creation. After the expiry time has elapsed,
the token will not be able create a new session
(default: {DEFAULT_SESSION_TOKEN_EXPIRATION})
Any additional keyword arguments are passed to ``tornado.web.Application``.
.. autoclasstoc::
'''
_loop: IOLoop
_applications: Mapping[str, ApplicationContext]
_prefix: str
_websocket_origins: Set[str]
auth_provider: AuthProvider
_clients: Set[ServerConnection]
def __init__(self,
applications: Mapping[str, Application | ModifyDoc] | Application | ModifyDoc,
prefix: str | None = None,
extra_websocket_origins: Sequence[str] | None = None,
extra_patterns: URLRoutes | None = None,
secret_key: bytes | None = settings.secret_key_bytes(),
sign_sessions: bool = settings.sign_sessions(),
generate_session_ids: bool = True,
keep_alive_milliseconds: int = DEFAULT_KEEP_ALIVE_MS,
check_unused_sessions_milliseconds: int = DEFAULT_CHECK_UNUSED_MS,
unused_session_lifetime_milliseconds: int = DEFAULT_UNUSED_LIFETIME_MS,
stats_log_frequency_milliseconds: int = DEFAULT_STATS_LOG_FREQ_MS,
mem_log_frequency_milliseconds: int = DEFAULT_MEM_LOG_FREQ_MS,
use_index: bool = True,
redirect_root: bool = True,
websocket_max_message_size_bytes: int = DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES,
websocket_compression_level: int | None = None,
websocket_compression_mem_level: int | None = None,
index: str | None = None,
auth_provider: AuthProvider = NullAuth(),
xsrf_cookies: bool = False,
include_headers: List[str] | None = None,
include_cookies: List[str] | None = None,
exclude_headers: List[str] | None = None,
exclude_cookies: List[str] | None = None,
session_token_expiration: int = DEFAULT_SESSION_TOKEN_EXPIRATION,
**kwargs):
# This will be set when initialize is called
self._loop = None
from bokeh.application.handlers.document_lifecycle import DocumentLifecycleHandler
from bokeh.application.handlers.function import FunctionHandler
if callable(applications):
applications = Application(FunctionHandler(applications))
if isinstance(applications, Application):
applications = {'/' : applications}
for url, app in list(applications.items()):
if callable(app):
applications[url] = app = Application(FunctionHandler(app))
if all(not isinstance(handler, DocumentLifecycleHandler) for handler in app._handlers):
app.add(DocumentLifecycleHandler())
if prefix is None:
prefix = ""
prefix = prefix.strip("/")
if prefix:
prefix = "/" + prefix
self._prefix = prefix
self._index = index
if keep_alive_milliseconds < 0:
# 0 means "disable"
raise ValueError("keep_alive_milliseconds must be >= 0")
else:
if keep_alive_milliseconds == 0:
log.info("Keep-alive ping disabled")
elif keep_alive_milliseconds != DEFAULT_KEEP_ALIVE_MS:
log.info("Keep-alive ping configured every %d milliseconds", keep_alive_milliseconds)
self._keep_alive_milliseconds = keep_alive_milliseconds
if check_unused_sessions_milliseconds <= 0:
raise ValueError("check_unused_sessions_milliseconds must be > 0")
elif check_unused_sessions_milliseconds != DEFAULT_CHECK_UNUSED_MS:
log.info("Check for unused sessions every %d milliseconds", check_unused_sessions_milliseconds)
self._check_unused_sessions_milliseconds = check_unused_sessions_milliseconds
if unused_session_lifetime_milliseconds <= 0:
raise ValueError("unused_session_lifetime_milliseconds must be > 0")
elif unused_session_lifetime_milliseconds != DEFAULT_UNUSED_LIFETIME_MS:
log.info("Unused sessions last for %d milliseconds", unused_session_lifetime_milliseconds)
self._unused_session_lifetime_milliseconds = unused_session_lifetime_milliseconds
if stats_log_frequency_milliseconds <= 0:
raise ValueError("stats_log_frequency_milliseconds must be > 0")
elif stats_log_frequency_milliseconds != DEFAULT_STATS_LOG_FREQ_MS:
log.info("Log statistics every %d milliseconds", stats_log_frequency_milliseconds)
self._stats_log_frequency_milliseconds = stats_log_frequency_milliseconds
if mem_log_frequency_milliseconds < 0:
# 0 means "disable"
raise ValueError("mem_log_frequency_milliseconds must be >= 0")
elif mem_log_frequency_milliseconds > 0:
if psutil is None:
log.warning("Memory logging requested, but is disabled. Optional dependency 'psutil' is missing. "
"Try 'pip install psutil' or 'conda install psutil'")
mem_log_frequency_milliseconds = 0
elif mem_log_frequency_milliseconds != DEFAULT_MEM_LOG_FREQ_MS:
log.info("Log memory usage every %d milliseconds", mem_log_frequency_milliseconds)
self._mem_log_frequency_milliseconds = mem_log_frequency_milliseconds
if websocket_max_message_size_bytes <= 0:
raise ValueError("websocket_max_message_size_bytes must be positive")
elif websocket_max_message_size_bytes != DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES:
log.info("Torndado websocket_max_message_size set to %d bytes (%0.2f MB)",
websocket_max_message_size_bytes,
websocket_max_message_size_bytes/1024.0**2)
self.auth_provider = auth_provider
if self.auth_provider.get_user or self.auth_provider.get_user_async:
log.info("User authentication hooks provided (no default user)")
else:
log.info("User authentication hooks NOT provided (default user enabled)")
kwargs['xsrf_cookies'] = xsrf_cookies
if xsrf_cookies:
log.info("XSRF cookie protection enabled")
if session_token_expiration <= 0:
raise ValueError("session_token_expiration must be > 0")
else:
self._session_token_expiration = session_token_expiration
if exclude_cookies and include_cookies:
raise ValueError("Declare either an include or an exclude list for the cookies, not both.")
self._exclude_cookies = exclude_cookies
self._include_cookies = include_cookies
if exclude_headers and include_headers:
raise ValueError("Declare either an include or an exclude list for the headers, not both.")
self._exclude_headers = exclude_headers
self._include_headers = include_headers
if extra_websocket_origins is None:
self._websocket_origins = set()
else:
self._websocket_origins = set(extra_websocket_origins)
self._secret_key = secret_key
self._sign_sessions = sign_sessions
self._generate_session_ids = generate_session_ids
log.debug("These host origins can connect to the websocket: %r", list(self._websocket_origins))
# Wrap applications in ApplicationContext
self._applications = {}
for url, app in applications.items():
self._applications[url] = ApplicationContext(app, url=url, logout_url=self.auth_provider.logout_url)
extra_patterns = extra_patterns or []
extra_patterns.extend(self.auth_provider.endpoints)
all_patterns: URLRoutes = []
for key, app in applications.items():
app_patterns: URLRoutes = []
for p in per_app_patterns:
if key == "/":
route = p[0]
else:
route = key + p[0]
context: RouteContext = {"application_context": self._applications[key]}
if issubclass(p[1], WSHandler):
context['compression_level'] = websocket_compression_level
context['mem_level'] = websocket_compression_mem_level
route = self._prefix + route
app_patterns.append((route, p[1], context))
websocket_path = None
for r in app_patterns:
if r[0].endswith("/ws"):
websocket_path = r[0]
if not websocket_path:
raise RuntimeError("Couldn't find websocket path")
for r in app_patterns:
r[2]["bokeh_websocket_path"] = websocket_path
all_patterns.extend(app_patterns)
# if the app requests a custom static path, use that, otherwise add Bokeh's standard static handler
all_patterns.append(create_static_handler(self._prefix, key, app))
for p in extra_patterns + toplevel_patterns:
if p[1] == RootHandler:
if use_index:
data = {
"applications": self._applications,
"prefix": self._prefix,
"index": self._index,
"use_redirect": redirect_root,
}
prefixed_pat = (self._prefix + p[0],) + p[1:] + (data,)
all_patterns.append(prefixed_pat)
else:
prefixed_pat = (self._prefix + p[0],) + p[1:]
all_patterns.append(prefixed_pat)
log.debug("Patterns are:")
for line in pformat(all_patterns, width=60).split("\n"):
log.debug(" " + line)
super().__init__(all_patterns,
websocket_max_message_size=websocket_max_message_size_bytes,
**kwargs)
[docs] def initialize(self, io_loop: IOLoop) -> None:
''' Start a Bokeh Server Tornado Application on a given Tornado IOLoop.
'''
self._loop = io_loop
for app_context in self._applications.values():
app_context._loop = self._loop
self._clients = set()
self._stats_job = PeriodicCallback(self._log_stats,
self._stats_log_frequency_milliseconds)
if self._mem_log_frequency_milliseconds > 0:
self._mem_job = PeriodicCallback(self._log_mem,
self._mem_log_frequency_milliseconds)
else:
self._mem_job = None
self._cleanup_job = PeriodicCallback(self._cleanup_sessions,
self._check_unused_sessions_milliseconds)
if self._keep_alive_milliseconds > 0:
self._ping_job = PeriodicCallback(self._keep_alive, self._keep_alive_milliseconds)
else:
self._ping_job = None
@property
def applications(self):
''' The configured applications
'''
return self._applications
@property
def app_paths(self) -> Set[str]:
''' A list of all application paths for all Bokeh applications
configured on this Bokeh server instance.
'''
return set(self._applications)
@property
def index(self) -> str | None:
''' Path to a Jinja2 template to serve as the index "/"
'''
return self._index
@property
def io_loop(self) -> IOLoop:
''' The Tornado IOLoop that this Bokeh Server Tornado Application
is running on.
'''
return self._loop
@property
def prefix(self) -> str:
''' A URL prefix for this Bokeh Server Tornado Application to use
for all paths
'''
return self._prefix
@property
def websocket_origins(self) -> Set[str]:
''' A list of websocket origins permitted to connect to this server.
'''
return self._websocket_origins
@property
def secret_key(self) -> bytes | None:
''' A secret key for this Bokeh Server Tornado Application to use when
signing session IDs, if configured.
'''
return self._secret_key
@property
def include_cookies(self) -> List[str] | None:
''' A list of request cookies to make available in the session
context.
'''
return self._include_cookies
@property
def include_headers(self) -> List[str] | None:
''' A list of request headers to make available in the session
context.
'''
return self._include_headers
@property
def exclude_cookies(self) -> List[str] | None:
''' A list of request cookies to exclude in the session context.
'''
return self._exclude_cookies
@property
def exclude_headers(self) -> List[str] | None:
''' A list of request headers to exclude in the session context.
'''
return self._exclude_headers
@property
def sign_sessions(self) -> bool:
''' Whether this Bokeh Server Tornado Application has been configured
to cryptographically sign session IDs
If ``True``, then ``secret_key`` must also have been configured.
'''
return self._sign_sessions
@property
def generate_session_ids(self) -> bool:
''' Whether this Bokeh Server Tornado Application has been configured
to automatically generate session IDs.
'''
return self._generate_session_ids
@property
def session_token_expiration(self) -> int:
''' Duration in seconds that a new session token is valid for
session creation.
After the expiry time has elapsed, the token will not be able
create a new session.
'''
return self._session_token_expiration
[docs] def resources(self, absolute_url: str | None = None) -> Resources:
''' Provide a :class:`~bokeh.resources.Resources` that specifies where
Bokeh application sessions should load BokehJS resources from.
Args:
absolute_url (bool):
An absolute URL prefix to use for locating resources. If None,
relative URLs are used (default: None)
'''
mode = settings.resources(default="server")
if mode == "server":
root_url = urljoin(absolute_url, self._prefix) if absolute_url else self._prefix
return Resources(mode="server", root_url=root_url, path_versioner=StaticHandler.append_version)
return Resources(mode=mode)
[docs] def start(self) -> None:
''' Start the Bokeh Server application.
Starting the Bokeh Server Tornado application will run periodic
callbacks for stats logging, cleanup, pinging, etc. Additionally, any
startup hooks defined by the configured Bokeh applications will be run.
'''
self._stats_job.start()
if self._mem_job is not None:
self._mem_job.start()
self._cleanup_job.start()
if self._ping_job is not None:
self._ping_job.start()
for context in self._applications.values():
self._loop.add_callback(context.run_load_hook)
[docs] def stop(self, wait: bool = True) -> None:
''' Stop the Bokeh Server application.
Args:
wait (bool): whether to wait for orderly cleanup (default: True)
Returns:
None
'''
# TODO should probably close all connections and shut down all sessions here
for context in self._applications.values():
context.run_unload_hook()
self._stats_job.stop()
if self._mem_job is not None:
self._mem_job.stop()
self._cleanup_job.stop()
if self._ping_job is not None:
self._ping_job.stop()
self._clients.clear()
def new_connection(self, protocol: Protocol, socket: WSHandler,
application_context: ApplicationContext, session: ServerSession) -> ServerConnection:
connection = ServerConnection(protocol, socket, application_context, session)
self._clients.add(connection)
return connection
def client_lost(self, connection: ServerConnection) -> None:
self._clients.discard(connection)
connection.detach_session()
[docs] def get_session(self, app_path: str, session_id: ID) -> ServerSession:
''' Get an active a session by name application path and session ID.
Args:
app_path (str) :
The configured application path for the application to return
a session for.
session_id (str) :
The session ID of the session to retrieve.
Returns:
ServerSession
'''
if app_path not in self._applications:
raise ValueError("Application %s does not exist on this server" % app_path)
return self._applications[app_path].get_session(session_id)
[docs] def get_sessions(self, app_path: str) -> List[ServerSession]:
''' Gets all currently active sessions for an application.
Args:
app_path (str) :
The configured application path for the application to return
sessions for.
Returns:
list[ServerSession]
'''
if app_path not in self._applications:
raise ValueError("Application %s does not exist on this server" % app_path)
return list(self._applications[app_path].sessions)
# Periodic Callbacks ------------------------------------------------------
async def _cleanup_sessions(self) -> None:
log.trace("Running session cleanup job")
for app in self._applications.values():
await app._cleanup_sessions(self._unused_session_lifetime_milliseconds)
return None
def _log_stats(self) -> None:
log.trace("Running stats log job")
if log.getEffectiveLevel() > logging.DEBUG:
# avoid the work below if we aren't going to log anything
return
log.debug("[pid %d] %d clients connected", PID, len(self._clients))
for app_path, app in self._applications.items():
sessions = list(app.sessions)
unused_count = 0
for s in sessions:
if s.connection_count == 0:
unused_count += 1
log.debug("[pid %d] %s has %d sessions with %d unused",
PID, app_path, len(sessions), unused_count)
def _log_mem(self) -> None:
# we should be able to assume PROC is define, if psutil is not installed
# then the _log_mem callback is not started at all
mem = PROC.memory_info()
log.info("[pid %d] Memory usage: %0.2f MB (RSS), %0.2f MB (VMS)", PID, mem.rss/GB, mem.vms/GB)
del mem
# skip the rest if we would not log it anyway
if log.getEffectiveLevel() > logging.DEBUG:
return
#from collections import Counter
# pprint.pprint(Counter([str(type(x)) for x in gc.get_objects() if "DataFrame" in str(type(x))]).most_common(30))
all_objs = gc.get_objects()
for name, typ in [('Documents', Document), ('Sessions', ServerSession), ('Models', Model)]:
objs = [x for x in all_objs if isinstance(x, typ)]
log.debug(f" uncollected {name}: {len(objs)}")
# uncomment for potentially voluminous referrers output
# if name == 'Models' and len(objs):
# import pprint
# for i in range(10):
# print(i, objs[i], gc.get_referents(objs[i]))
objs = [x for x in gc.get_objects() if isinstance(x, ModuleType) and "bokeh_app_" in str(x)]
log.debug(f" uncollected modules: {len(objs)}")
if pd:
objs = [x for x in all_objs if isinstance(x, pd.DataFrame)]
log.debug(" uncollected DataFrames: %d", len(objs))
# uncomment (and install pympler) for mem usage by type report
# from operator import itemgetter
# import pprint
# from pympler import tracker
# mem = tracker.SummaryTracker()
# pprint.pprint(sorted(mem.create_summary(), reverse=True, key=itemgetter(2))[:30])
def _keep_alive(self) -> None:
log.trace("Running keep alive job")
for c in self._clients:
c.send_ping()
#-----------------------------------------------------------------------------
# Dev API
#-----------------------------------------------------------------------------
def create_static_handler(prefix: str, key: str, app: Application) -> Tuple[str, StaticFileHandler|StaticHandler, Dict[str, Any]]:
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, {})
#-----------------------------------------------------------------------------
# Private API
#-----------------------------------------------------------------------------
#-----------------------------------------------------------------------------
# Code
#-----------------------------------------------------------------------------
BokehTornado.__doc__ = format_docstring(
BokehTornado.__doc__,
DEFAULT_CHECK_UNUSED_MS=DEFAULT_CHECK_UNUSED_MS,
DEFAULT_KEEP_ALIVE_MS=DEFAULT_KEEP_ALIVE_MS,
DEFAULT_MEM_LOG_FREQ_MS=DEFAULT_MEM_LOG_FREQ_MS,
DEFAULT_STATS_LOG_FREQ_MS=DEFAULT_STATS_LOG_FREQ_MS,
DEFAULT_UNUSED_LIFETIME_MS=DEFAULT_UNUSED_LIFETIME_MS,
DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES=DEFAULT_WEBSOCKET_MAX_MESSAGE_SIZE_BYTES,
DEFAULT_SESSION_TOKEN_EXPIRATION=DEFAULT_SESSION_TOKEN_EXPIRATION,
)
fixup_windows_event_loop_policy()