|
|
"""Base class to manage a running kernel"""
|
|
|
|
|
|
# Copyright (c) IPython Development Team.
|
|
|
# Distributed under the terms of the Modified BSD License.
|
|
|
|
|
|
from __future__ import absolute_import
|
|
|
|
|
|
from contextlib import contextmanager
|
|
|
import os
|
|
|
import re
|
|
|
import signal
|
|
|
import sys
|
|
|
import time
|
|
|
import warnings
|
|
|
try:
|
|
|
from queue import Empty # Py 3
|
|
|
except ImportError:
|
|
|
from Queue import Empty # Py 2
|
|
|
|
|
|
import zmq
|
|
|
|
|
|
from IPython.utils.importstring import import_item
|
|
|
from IPython.utils.localinterfaces import is_local_ip, local_ips
|
|
|
from IPython.utils.path import get_ipython_dir
|
|
|
from IPython.utils.traitlets import (
|
|
|
Any, Instance, Unicode, List, Bool, Type, DottedObjectName
|
|
|
)
|
|
|
from IPython.kernel import (
|
|
|
launch_kernel,
|
|
|
kernelspec,
|
|
|
)
|
|
|
from .connect import ConnectionFileMixin
|
|
|
from .zmq.session import Session
|
|
|
from .managerabc import (
|
|
|
KernelManagerABC
|
|
|
)
|
|
|
|
|
|
|
|
|
class KernelManager(ConnectionFileMixin):
|
|
|
"""Manages a single kernel in a subprocess on this host.
|
|
|
|
|
|
This version starts kernels with Popen.
|
|
|
"""
|
|
|
|
|
|
# The PyZMQ Context to use for communication with the kernel.
|
|
|
context = Instance(zmq.Context)
|
|
|
def _context_default(self):
|
|
|
return zmq.Context.instance()
|
|
|
|
|
|
# the class to create with our `client` method
|
|
|
client_class = DottedObjectName('IPython.kernel.blocking.BlockingKernelClient')
|
|
|
client_factory = Type()
|
|
|
def _client_class_changed(self, name, old, new):
|
|
|
self.client_factory = import_item(str(new))
|
|
|
|
|
|
# The kernel process with which the KernelManager is communicating.
|
|
|
# generally a Popen instance
|
|
|
kernel = Any()
|
|
|
|
|
|
kernel_spec_manager = Instance(kernelspec.KernelSpecManager)
|
|
|
|
|
|
def _kernel_spec_manager_default(self):
|
|
|
return kernelspec.KernelSpecManager(ipython_dir=self.ipython_dir)
|
|
|
|
|
|
kernel_name = Unicode(kernelspec.NATIVE_KERNEL_NAME)
|
|
|
|
|
|
kernel_spec = Instance(kernelspec.KernelSpec)
|
|
|
|
|
|
def _kernel_spec_default(self):
|
|
|
return self.kernel_spec_manager.get_kernel_spec(self.kernel_name)
|
|
|
|
|
|
def _kernel_name_changed(self, name, old, new):
|
|
|
if new == 'python':
|
|
|
self.kernel_name = kernelspec.NATIVE_KERNEL_NAME
|
|
|
# This triggered another run of this function, so we can exit now
|
|
|
return
|
|
|
self.kernel_spec = self.kernel_spec_manager.get_kernel_spec(new)
|
|
|
self.ipython_kernel = new in {'python', 'python2', 'python3'}
|
|
|
|
|
|
kernel_cmd = List(Unicode, config=True,
|
|
|
help="""DEPRECATED: Use kernel_name instead.
|
|
|
|
|
|
The Popen Command to launch the kernel.
|
|
|
Override this if you have a custom kernel.
|
|
|
If kernel_cmd is specified in a configuration file,
|
|
|
IPython does not pass any arguments to the kernel,
|
|
|
because it cannot make any assumptions about the
|
|
|
arguments that the kernel understands. In particular,
|
|
|
this means that the kernel does not receive the
|
|
|
option --debug if it given on the IPython command line.
|
|
|
"""
|
|
|
)
|
|
|
|
|
|
def _kernel_cmd_changed(self, name, old, new):
|
|
|
warnings.warn("Setting kernel_cmd is deprecated, use kernel_spec to "
|
|
|
"start different kernels.")
|
|
|
self.ipython_kernel = False
|
|
|
|
|
|
ipython_kernel = Bool(True)
|
|
|
|
|
|
ipython_dir = Unicode()
|
|
|
def _ipython_dir_default(self):
|
|
|
return get_ipython_dir()
|
|
|
|
|
|
# Protected traits
|
|
|
_launch_args = Any()
|
|
|
_control_socket = Any()
|
|
|
|
|
|
_restarter = Any()
|
|
|
|
|
|
autorestart = Bool(False, config=True,
|
|
|
help="""Should we autorestart the kernel if it dies."""
|
|
|
)
|
|
|
|
|
|
def __del__(self):
|
|
|
self._close_control_socket()
|
|
|
self.cleanup_connection_file()
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# Kernel restarter
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
def start_restarter(self):
|
|
|
pass
|
|
|
|
|
|
def stop_restarter(self):
|
|
|
pass
|
|
|
|
|
|
def add_restart_callback(self, callback, event='restart'):
|
|
|
"""register a callback to be called when a kernel is restarted"""
|
|
|
if self._restarter is None:
|
|
|
return
|
|
|
self._restarter.add_callback(callback, event)
|
|
|
|
|
|
def remove_restart_callback(self, callback, event='restart'):
|
|
|
"""unregister a callback to be called when a kernel is restarted"""
|
|
|
if self._restarter is None:
|
|
|
return
|
|
|
self._restarter.remove_callback(callback, event)
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# create a Client connected to our Kernel
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
def client(self, **kwargs):
|
|
|
"""Create a client configured to connect to our kernel"""
|
|
|
if self.client_factory is None:
|
|
|
self.client_factory = import_item(self.client_class)
|
|
|
|
|
|
kw = {}
|
|
|
kw.update(self.get_connection_info())
|
|
|
kw.update(dict(
|
|
|
connection_file=self.connection_file,
|
|
|
session=self.session,
|
|
|
parent=self,
|
|
|
))
|
|
|
|
|
|
# add kwargs last, for manual overrides
|
|
|
kw.update(kwargs)
|
|
|
return self.client_factory(**kw)
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# Kernel management
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
def format_kernel_cmd(self, extra_arguments=None):
|
|
|
"""replace templated args (e.g. {connection_file})"""
|
|
|
extra_arguments = extra_arguments or []
|
|
|
if self.kernel_cmd:
|
|
|
cmd = self.kernel_cmd + extra_arguments
|
|
|
else:
|
|
|
cmd = self.kernel_spec.argv + extra_arguments
|
|
|
|
|
|
ns = dict(connection_file=self.connection_file)
|
|
|
ns.update(self._launch_args)
|
|
|
|
|
|
pat = re.compile(r'\{([A-Za-z0-9_]+)\}')
|
|
|
def from_ns(match):
|
|
|
"""Get the key out of ns if it's there, otherwise no change."""
|
|
|
return ns.get(match.group(1), match.group())
|
|
|
|
|
|
return [ pat.sub(from_ns, arg) for arg in cmd ]
|
|
|
|
|
|
def _launch_kernel(self, kernel_cmd, **kw):
|
|
|
"""actually launch the kernel
|
|
|
|
|
|
override in a subclass to launch kernel subprocesses differently
|
|
|
"""
|
|
|
return launch_kernel(kernel_cmd, **kw)
|
|
|
|
|
|
# Control socket used for polite kernel shutdown
|
|
|
|
|
|
def _connect_control_socket(self):
|
|
|
if self._control_socket is None:
|
|
|
self._control_socket = self.connect_control()
|
|
|
self._control_socket.linger = 100
|
|
|
|
|
|
def _close_control_socket(self):
|
|
|
if self._control_socket is None:
|
|
|
return
|
|
|
self._control_socket.close()
|
|
|
self._control_socket = None
|
|
|
|
|
|
def start_kernel(self, **kw):
|
|
|
"""Starts a kernel on this host in a separate process.
|
|
|
|
|
|
If random ports (port=0) are being used, this method must be called
|
|
|
before the channels are created.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
**kw : optional
|
|
|
keyword arguments that are passed down to build the kernel_cmd
|
|
|
and launching the kernel (e.g. Popen kwargs).
|
|
|
"""
|
|
|
if self.transport == 'tcp' and not is_local_ip(self.ip):
|
|
|
raise RuntimeError("Can only launch a kernel on a local interface. "
|
|
|
"Make sure that the '*_address' attributes are "
|
|
|
"configured properly. "
|
|
|
"Currently valid addresses are: %s" % local_ips()
|
|
|
)
|
|
|
|
|
|
# write connection file / get default ports
|
|
|
self.write_connection_file()
|
|
|
|
|
|
# save kwargs for use in restart
|
|
|
self._launch_args = kw.copy()
|
|
|
# build the Popen cmd
|
|
|
extra_arguments = kw.pop('extra_arguments', [])
|
|
|
kernel_cmd = self.format_kernel_cmd(extra_arguments=extra_arguments)
|
|
|
if self.kernel_cmd:
|
|
|
# If kernel_cmd has been set manually, don't refer to a kernel spec
|
|
|
env = os.environ
|
|
|
else:
|
|
|
# Environment variables from kernel spec are added to os.environ
|
|
|
env = os.environ.copy()
|
|
|
env.update(self.kernel_spec.env or {})
|
|
|
# launch the kernel subprocess
|
|
|
self.kernel = self._launch_kernel(kernel_cmd, env=env,
|
|
|
**kw)
|
|
|
self.start_restarter()
|
|
|
self._connect_control_socket()
|
|
|
|
|
|
def request_shutdown(self, restart=False):
|
|
|
"""Send a shutdown request via control channel
|
|
|
|
|
|
On Windows, this just kills kernels instead, because the shutdown
|
|
|
messages don't work.
|
|
|
"""
|
|
|
content = dict(restart=restart)
|
|
|
msg = self.session.msg("shutdown_request", content=content)
|
|
|
self.session.send(self._control_socket, msg)
|
|
|
|
|
|
def finish_shutdown(self, waittime=1, pollinterval=0.1):
|
|
|
"""Wait for kernel shutdown, then kill process if it doesn't shutdown.
|
|
|
|
|
|
This does not send shutdown requests - use :meth:`request_shutdown`
|
|
|
first.
|
|
|
"""
|
|
|
for i in range(int(waittime/pollinterval)):
|
|
|
if self.is_alive():
|
|
|
time.sleep(pollinterval)
|
|
|
else:
|
|
|
break
|
|
|
else:
|
|
|
# OK, we've waited long enough.
|
|
|
if self.has_kernel:
|
|
|
self._kill_kernel()
|
|
|
|
|
|
def cleanup(self, connection_file=True):
|
|
|
"""Clean up resources when the kernel is shut down"""
|
|
|
if connection_file:
|
|
|
self.cleanup_connection_file()
|
|
|
|
|
|
self.cleanup_ipc_files()
|
|
|
self._close_control_socket()
|
|
|
|
|
|
def shutdown_kernel(self, now=False, restart=False):
|
|
|
"""Attempts to the stop the kernel process cleanly.
|
|
|
|
|
|
This attempts to shutdown the kernels cleanly by:
|
|
|
|
|
|
1. Sending it a shutdown message over the shell channel.
|
|
|
2. If that fails, the kernel is shutdown forcibly by sending it
|
|
|
a signal.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
now : bool
|
|
|
Should the kernel be forcible killed *now*. This skips the
|
|
|
first, nice shutdown attempt.
|
|
|
restart: bool
|
|
|
Will this kernel be restarted after it is shutdown. When this
|
|
|
is True, connection files will not be cleaned up.
|
|
|
"""
|
|
|
# Stop monitoring for restarting while we shutdown.
|
|
|
self.stop_restarter()
|
|
|
|
|
|
if now:
|
|
|
self._kill_kernel()
|
|
|
else:
|
|
|
self.request_shutdown(restart=restart)
|
|
|
# Don't send any additional kernel kill messages immediately, to give
|
|
|
# the kernel a chance to properly execute shutdown actions. Wait for at
|
|
|
# most 1s, checking every 0.1s.
|
|
|
self.finish_shutdown()
|
|
|
|
|
|
self.cleanup(connection_file=not restart)
|
|
|
|
|
|
def restart_kernel(self, now=False, **kw):
|
|
|
"""Restarts a kernel with the arguments that were used to launch it.
|
|
|
|
|
|
If the old kernel was launched with random ports, the same ports will be
|
|
|
used for the new kernel. The same connection file is used again.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
now : bool, optional
|
|
|
If True, the kernel is forcefully restarted *immediately*, without
|
|
|
having a chance to do any cleanup action. Otherwise the kernel is
|
|
|
given 1s to clean up before a forceful restart is issued.
|
|
|
|
|
|
In all cases the kernel is restarted, the only difference is whether
|
|
|
it is given a chance to perform a clean shutdown or not.
|
|
|
|
|
|
**kw : optional
|
|
|
Any options specified here will overwrite those used to launch the
|
|
|
kernel.
|
|
|
"""
|
|
|
if self._launch_args is None:
|
|
|
raise RuntimeError("Cannot restart the kernel. "
|
|
|
"No previous call to 'start_kernel'.")
|
|
|
else:
|
|
|
# Stop currently running kernel.
|
|
|
self.shutdown_kernel(now=now, restart=True)
|
|
|
|
|
|
# Start new kernel.
|
|
|
self._launch_args.update(kw)
|
|
|
self.start_kernel(**self._launch_args)
|
|
|
|
|
|
@property
|
|
|
def has_kernel(self):
|
|
|
"""Has a kernel been started that we are managing."""
|
|
|
return self.kernel is not None
|
|
|
|
|
|
def _kill_kernel(self):
|
|
|
"""Kill the running kernel.
|
|
|
|
|
|
This is a private method, callers should use shutdown_kernel(now=True).
|
|
|
"""
|
|
|
if self.has_kernel:
|
|
|
|
|
|
# Signal the kernel to terminate (sends SIGKILL on Unix and calls
|
|
|
# TerminateProcess() on Win32).
|
|
|
try:
|
|
|
self.kernel.kill()
|
|
|
except OSError as e:
|
|
|
# In Windows, we will get an Access Denied error if the process
|
|
|
# has already terminated. Ignore it.
|
|
|
if sys.platform == 'win32':
|
|
|
if e.winerror != 5:
|
|
|
raise
|
|
|
# On Unix, we may get an ESRCH error if the process has already
|
|
|
# terminated. Ignore it.
|
|
|
else:
|
|
|
from errno import ESRCH
|
|
|
if e.errno != ESRCH:
|
|
|
raise
|
|
|
|
|
|
# Block until the kernel terminates.
|
|
|
self.kernel.wait()
|
|
|
self.kernel = None
|
|
|
else:
|
|
|
raise RuntimeError("Cannot kill kernel. No kernel is running!")
|
|
|
|
|
|
def interrupt_kernel(self):
|
|
|
"""Interrupts the kernel by sending it a signal.
|
|
|
|
|
|
Unlike ``signal_kernel``, this operation is well supported on all
|
|
|
platforms.
|
|
|
"""
|
|
|
if self.has_kernel:
|
|
|
if sys.platform == 'win32':
|
|
|
from .zmq.parentpoller import ParentPollerWindows as Poller
|
|
|
Poller.send_interrupt(self.kernel.win32_interrupt_event)
|
|
|
else:
|
|
|
self.kernel.send_signal(signal.SIGINT)
|
|
|
else:
|
|
|
raise RuntimeError("Cannot interrupt kernel. No kernel is running!")
|
|
|
|
|
|
def signal_kernel(self, signum):
|
|
|
"""Sends a signal to the kernel.
|
|
|
|
|
|
Note that since only SIGTERM is supported on Windows, this function is
|
|
|
only useful on Unix systems.
|
|
|
"""
|
|
|
if self.has_kernel:
|
|
|
self.kernel.send_signal(signum)
|
|
|
else:
|
|
|
raise RuntimeError("Cannot signal kernel. No kernel is running!")
|
|
|
|
|
|
def is_alive(self):
|
|
|
"""Is the kernel process still running?"""
|
|
|
if self.has_kernel:
|
|
|
if self.kernel.poll() is None:
|
|
|
return True
|
|
|
else:
|
|
|
return False
|
|
|
else:
|
|
|
# we don't have a kernel
|
|
|
return False
|
|
|
|
|
|
|
|
|
KernelManagerABC.register(KernelManager)
|
|
|
|
|
|
|
|
|
def start_new_kernel(startup_timeout=60, kernel_name='python', **kwargs):
|
|
|
"""Start a new kernel, and return its Manager and Client"""
|
|
|
km = KernelManager(kernel_name=kernel_name)
|
|
|
km.start_kernel(**kwargs)
|
|
|
kc = km.client()
|
|
|
kc.start_channels()
|
|
|
|
|
|
kc.kernel_info()
|
|
|
kc.get_shell_msg(block=True, timeout=startup_timeout)
|
|
|
|
|
|
# Flush channels
|
|
|
for channel in (kc.shell_channel, kc.iopub_channel):
|
|
|
while True:
|
|
|
try:
|
|
|
channel.get_msg(block=True, timeout=0.1)
|
|
|
except Empty:
|
|
|
break
|
|
|
return km, kc
|
|
|
|
|
|
@contextmanager
|
|
|
def run_kernel(**kwargs):
|
|
|
"""Context manager to create a kernel in a subprocess.
|
|
|
|
|
|
The kernel is shut down when the context exits.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
kernel_client: connected KernelClient instance
|
|
|
"""
|
|
|
km, kc = start_new_kernel(**kwargs)
|
|
|
try:
|
|
|
yield kc
|
|
|
finally:
|
|
|
kc.stop_channels()
|
|
|
km.shutdown_kernel(now=True)
|
|
|
|
