Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/notebook/terminal/terminalmanager.py

151 lines
6.2 KiB
Python

"""A MultiTerminalManager for use in the notebook webserver
- raises HTTPErrors
- creates REST API models
"""
# Copyright (c) Jupyter Development Team.
# Distributed under the terms of the Modified BSD License.
import warnings
from datetime import timedelta
from notebook._tz import utcnow, isoformat
from terminado import NamedTermManager
from tornado import web
from tornado.ioloop import IOLoop, PeriodicCallback
from traitlets import Integer, validate
from traitlets.config import LoggingConfigurable
from ..prometheus.metrics import TERMINAL_CURRENTLY_RUNNING_TOTAL
class TerminalManager(LoggingConfigurable, NamedTermManager):
""" """
_culler_callback = None
_initialized_culler = False
cull_inactive_timeout = Integer(0, config=True,
help="""Timeout (in seconds) in which a terminal has been inactive and ready to be culled.
Values of 0 or lower disable culling."""
)
cull_interval_default = 300 # 5 minutes
cull_interval = Integer(cull_interval_default, config=True,
help="""The interval (in seconds) on which to check for terminals exceeding the inactive timeout value."""
)
# -------------------------------------------------------------------------
# Methods for managing terminals
# -------------------------------------------------------------------------
def __init__(self, *args, **kwargs):
super(TerminalManager, self).__init__(*args, **kwargs)
def create(self):
"""Create a new terminal."""
name, term = self.new_named_terminal()
# Monkey-patch last-activity, similar to kernels. Should we need
# more functionality per terminal, we can look into possible sub-
# classing or containment then.
term.last_activity = utcnow()
model = self.get_terminal_model(name)
# Increase the metric by one because a new terminal was created
TERMINAL_CURRENTLY_RUNNING_TOTAL.inc()
# Ensure culler is initialized
self._initialize_culler()
return model
def get(self, name):
"""Get terminal 'name'."""
model = self.get_terminal_model(name)
return model
def list(self):
"""Get a list of all running terminals."""
models = [self.get_terminal_model(name) for name in self.terminals]
# Update the metric below to the length of the list 'terms'
TERMINAL_CURRENTLY_RUNNING_TOTAL.set(
len(models)
)
return models
async def terminate(self, name, force=False):
"""Terminate terminal 'name'."""
self._check_terminal(name)
await super(TerminalManager, self).terminate(name, force=force)
# Decrease the metric below by one
# because a terminal has been shutdown
TERMINAL_CURRENTLY_RUNNING_TOTAL.dec()
async def terminate_all(self):
"""Terminate all terminals."""
terms = [name for name in self.terminals]
for term in terms:
await self.terminate(term, force=True)
def get_terminal_model(self, name):
"""Return a JSON-safe dict representing a terminal.
For use in representing terminals in the JSON APIs.
"""
self._check_terminal(name)
term = self.terminals[name]
model = {
"name": name,
"last_activity": isoformat(term.last_activity),
}
return model
def _check_terminal(self, name):
"""Check a that terminal 'name' exists and raise 404 if not."""
if name not in self.terminals:
raise web.HTTPError(404, u'Terminal not found: %s' % name)
def _initialize_culler(self):
"""Start culler if 'cull_inactive_timeout' is greater than zero.
Regardless of that value, set flag that we've been here.
"""
if not self._initialized_culler and self.cull_inactive_timeout > 0:
if self._culler_callback is None:
loop = IOLoop.current()
if self.cull_interval <= 0: # handle case where user set invalid value
self.log.warning("Invalid value for 'cull_interval' detected (%s) - using default value (%s).",
self.cull_interval, self.cull_interval_default)
self.cull_interval = self.cull_interval_default
self._culler_callback = PeriodicCallback(
self._cull_terminals, 1000 * self.cull_interval)
self.log.info("Culling terminals with inactivity > %s seconds at %s second intervals ...",
self.cull_inactive_timeout, self.cull_interval)
self._culler_callback.start()
self._initialized_culler = True
async def _cull_terminals(self):
self.log.debug("Polling every %s seconds for terminals inactive for > %s seconds...",
self.cull_interval, self.cull_inactive_timeout)
# Create a separate list of terminals to avoid conflicting updates while iterating
for name in list(self.terminals):
try:
await self._cull_inactive_terminal(name)
except Exception as e:
self.log.exception("The following exception was encountered while checking the "
"activity of terminal {}: {}".format(name, e))
async def _cull_inactive_terminal(self, name):
try:
term = self.terminals[name]
except KeyError:
return # KeyErrors are somewhat expected since the terminal can be terminated as the culling check is made.
self.log.debug("name=%s, last_activity=%s", name, term.last_activity)
if hasattr(term, 'last_activity'):
dt_now = utcnow()
dt_inactive = dt_now - term.last_activity
# Compute idle properties
is_time = dt_inactive > timedelta(seconds=self.cull_inactive_timeout)
# Cull the kernel if all three criteria are met
if (is_time):
inactivity = int(dt_inactive.total_seconds())
self.log.warning("Culling terminal '%s' due to %s seconds of inactivity.", name, inactivity)
await self.terminate(name, force=True)