''' Provides a Server which instantiates Application instances as clients connect
'''
from __future__ import absolute_import, print_function
import atexit
import logging
log = logging.getLogger(__name__)
import signal
from tornado.httpserver import HTTPServer
from tornado.ioloop import IOLoop
from tornado import netutil
from .tornado import BokehTornado
from bokeh import __version__
from bokeh.application import Application
from bokeh.resources import DEFAULT_SERVER_PORT
def _create_hosts_whitelist(host_list, port):
if not host_list:
return ['localhost:' + str(port)]
hosts = []
for host in host_list:
if '*' in host:
log.warning('Host wildcard %r can expose the application to HTTP '
'host header attacks. Host wildcard should only be '
'used for testing purpose.', host)
if host == '*':
# do not append the :80 port suffix in that case: any port is
# accepted
hosts.append(host)
continue
parts = host.split(':')
if len(parts) == 1:
if parts[0] == "":
raise ValueError("Empty host value")
hosts.append(host+":80")
elif len(parts) == 2:
try:
int(parts[1])
except ValueError:
raise ValueError("Invalid port in host value: %s" % host)
if parts[0] == "":
raise ValueError("Empty host value")
hosts.append(host)
else:
raise ValueError("Invalid host value: %s" % host)
return hosts
def _bind_sockets(address, port):
'''Like tornado.netutil.bind_sockets(), but also returns the
assigned port number.
'''
ss = netutil.bind_sockets(port=port or 0, address=address)
assert len(ss)
ports = {s.getsockname()[1] for s in ss}
assert len(ports) == 1, "Multiple ports assigned??"
actual_port = ports.pop()
if port:
assert actual_port == port
return ss, actual_port
[docs]class Server(object):
''' A Server which creates a new Session for each connection, using an Application to initialize each Session.
Args:
applications (dict of str: bokeh.application.Application) or bokeh.application.Application:
mapping from URL paths to Application instances, or a single Application to put at the root URL
The Application is a factory for Document, with a new Document initialized for each Session.
Each application should be identified by a path meant to go in a URL, like "/" or "/foo"
Kwargs:
num_procs (str):
Number of worker processes for an app. Default to one. Using 0 will autodetect number of cores
'''
def __init__(self, applications, io_loop=None, **kwargs):
log.info("Starting Bokeh server version %s" % __version__)
if isinstance(applications, Application):
self._applications = { '/' : applications }
else:
self._applications = applications
tornado_kwargs = { key: kwargs[key] for key in ['extra_patterns',
'secret_key',
'sign_sessions',
'generate_session_ids',
'keep_alive_milliseconds',
'check_unused_sessions_milliseconds',
'unused_session_lifetime_milliseconds',
'stats_log_frequency_milliseconds']
if key in kwargs }
prefix = kwargs.get('prefix')
if prefix is None:
prefix = ""
prefix = prefix.strip("/")
if prefix:
prefix = "/" + prefix
self._prefix = prefix
self._started = False
self._stopped = False
port = kwargs.get('port', DEFAULT_SERVER_PORT)
self._address = kwargs.get('address') or None
self._num_procs = kwargs.get('num_procs', 1)
if self._num_procs != 1:
assert all(app.safe_to_fork for app in self._applications.values()), (
'User code has ran before attempting to run multiple '
'processes. This is considered an unsafe operation.')
sockets, self._port = _bind_sockets(self._address, port)
try:
tornado_kwargs['hosts'] = _create_hosts_whitelist(kwargs.get('host'), self._port)
tornado_kwargs['extra_websocket_origins'] = _create_hosts_whitelist(kwargs.get('allow_websocket_origin'), self._port)
tornado_kwargs['use_index'] = kwargs.get('use_index', True)
tornado_kwargs['redirect_root'] = kwargs.get('redirect_root', True)
self._tornado = BokehTornado(self._applications, self.prefix, **tornado_kwargs)
self._http = HTTPServer(self._tornado, xheaders=kwargs.get('use_xheaders', False))
self._http.start(self._num_procs)
self._http.add_sockets(sockets)
except Exception:
for s in sockets:
s.close()
raise
# Can only instantiate the IO loop after HTTPServer.start() was
# called because of `num_procs`, see issue #5524
if io_loop is None:
io_loop = IOLoop.current()
self._loop = io_loop
self._tornado.initialize(io_loop=io_loop, **tornado_kwargs)
@property
def port(self):
'''The actual port number the server is listening on for HTTP
requests.
'''
return self._port
@property
def address(self):
'''The address the server is listening on for HTTP requests
(may be empty or None).
'''
return self._address
@property
def prefix(self):
return self._prefix
@property
def io_loop(self):
return self._loop
[docs] def start(self):
''' Start the Bokeh Server and its background tasks.
Notes:
This method does not block and does not affect the state of
the Tornado I/O loop. You must start and stop the loop yourself.
'''
assert not self._started, "Already started"
self._started = True
self._tornado.start()
[docs] def stop(self, wait=True):
''' Stop the Bokeh Server.
Args:
fast (boolean): whether to wait for orderly cleanup (default: True)
Returns:
None
'''
assert not self._stopped, "Already stopped"
self._stopped = True
self._tornado.stop(wait)
[docs] def run_until_shutdown(self):
''' Run the Bokeh Server until shutdown is requested by the user,
either via a Keyboard interrupt (Ctrl-C) or SIGTERM.
'''
if not self._started:
self.start()
# Install shutdown hooks
atexit.register(self._atexit)
signal.signal(signal.SIGTERM, self._sigterm)
try:
self._loop.start()
except KeyboardInterrupt:
print("\nInterrupted, shutting down")
self.stop()
_atexit_ran = False
def _atexit(self):
if self._atexit_ran:
return
self._atexit_ran = True
log.debug("Shutdown: cleaning up")
if not self._stopped:
self.stop(wait=False)
def _sigterm(self, signum, frame):
print("Received signal %d, shutting down" % (signum,))
# Tell self._loop.start() to return.
self._loop.add_callback_from_signal(self._loop.stop)
[docs] def unlisten(self):
'''Stop listening on ports (Server will no longer be usable after calling this)
Returns:
None
'''
self._http.close_all_connections()
self._http.stop()
[docs] def get_session(self, app_path, session_id):
'''Gets a session by name (session must already exist)'''
return self._tornado.get_session(app_path, session_id)
[docs] def get_sessions(self, app_path):
'''Gets all live sessions for an application.'''
return self._tornado.get_sessions(app_path)
[docs] def show(self, app_path, browser=None, new='tab'):
''' Opens an app in a browser window or tab.
Useful for testing server applications on your local desktop but
should not call when running bokeh-server on an actual server.
Args:
app_path (str) : the app path to open
The part of the URL after the hostname:port, with leading slash.
browser (str, optional) : browser to show with (default: None)
For systems that support it, the **browser** argument allows
specifying which browser to display in, e.g. "safari", "firefox",
"opera", "windows-default" (see the ``webbrowser`` module
documentation in the standard lib for more details).
new (str, optional) : window or tab (default: "tab")
If ``new`` is 'tab', then opens a new tab.
If ``new`` is 'window', then opens a new window.
Returns:
None
'''
if not app_path.startswith("/"):
raise ValueError("app_path must start with a /")
from bokeh.util.browser import view
url = "http://localhost:%d%s%s" % (self.port, self.prefix, app_path)
view(url, browser=browser, new=new)
