You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
311 lines
9.2 KiB
Python
311 lines
9.2 KiB
Python
""" Defines a KernelClient that provides thread-safe sockets with async callbacks on message
|
|
replies.
|
|
"""
|
|
import asyncio
|
|
import atexit
|
|
import errno
|
|
import time
|
|
from threading import Event
|
|
from threading import Thread
|
|
from typing import Any
|
|
from typing import Awaitable
|
|
from typing import Dict
|
|
from typing import List
|
|
from typing import Optional
|
|
from typing import Union
|
|
|
|
import nest_asyncio # type:ignore
|
|
import zmq
|
|
from traitlets import Instance
|
|
from traitlets import Type
|
|
from zmq import ZMQError
|
|
from zmq.eventloop import ioloop
|
|
from zmq.eventloop import zmqstream
|
|
|
|
from .session import Session
|
|
from jupyter_client import KernelClient
|
|
from jupyter_client.channels import HBChannel
|
|
|
|
# Local imports
|
|
# import ZMQError in top-level namespace, to avoid ugly attribute-error messages
|
|
# during garbage collection of threads at exit
|
|
|
|
|
|
async def get_msg(msg: Awaitable) -> Union[List[bytes], List[zmq.Message]]:
|
|
return await msg
|
|
|
|
|
|
class ThreadedZMQSocketChannel(object):
|
|
"""A ZMQ socket invoking a callback in the ioloop"""
|
|
|
|
session = None
|
|
socket = None
|
|
ioloop = None
|
|
stream = None
|
|
_inspect = None
|
|
|
|
def __init__(
|
|
self,
|
|
socket: Optional[zmq.Socket],
|
|
session: Optional[Session],
|
|
loop: Optional[zmq.eventloop.ioloop.ZMQIOLoop],
|
|
) -> None:
|
|
"""Create a channel.
|
|
|
|
Parameters
|
|
----------
|
|
socket : :class:`zmq.Socket`
|
|
The ZMQ socket to use.
|
|
session : :class:`session.Session`
|
|
The session to use.
|
|
loop
|
|
A pyzmq ioloop to connect the socket to using a ZMQStream
|
|
"""
|
|
super().__init__()
|
|
|
|
self.socket = socket
|
|
self.session = session
|
|
self.ioloop = loop
|
|
evt = Event()
|
|
|
|
def setup_stream():
|
|
assert self.socket is not None
|
|
self.stream = zmqstream.ZMQStream(self.socket, self.ioloop)
|
|
self.stream.on_recv(self._handle_recv) # type:ignore[arg-type]
|
|
evt.set()
|
|
|
|
assert self.ioloop is not None
|
|
self.ioloop.add_callback(setup_stream)
|
|
evt.wait()
|
|
|
|
_is_alive = False
|
|
|
|
def is_alive(self) -> bool:
|
|
return self._is_alive
|
|
|
|
def start(self) -> None:
|
|
self._is_alive = True
|
|
|
|
def stop(self) -> None:
|
|
self._is_alive = False
|
|
|
|
def close(self) -> None:
|
|
if self.socket is not None:
|
|
try:
|
|
self.socket.close(linger=0)
|
|
except Exception:
|
|
pass
|
|
self.socket = None
|
|
|
|
def send(self, msg: Dict[str, Any]) -> None:
|
|
"""Queue a message to be sent from the IOLoop's thread.
|
|
|
|
Parameters
|
|
----------
|
|
msg : message to send
|
|
|
|
This is threadsafe, as it uses IOLoop.add_callback to give the loop's
|
|
thread control of the action.
|
|
"""
|
|
|
|
def thread_send():
|
|
assert self.session is not None
|
|
self.session.send(self.stream, msg)
|
|
|
|
assert self.ioloop is not None
|
|
self.ioloop.add_callback(thread_send)
|
|
|
|
def _handle_recv(self, future_msg: Awaitable) -> None:
|
|
"""Callback for stream.on_recv.
|
|
|
|
Unpacks message, and calls handlers with it.
|
|
"""
|
|
assert self.ioloop is not None
|
|
msg_list = self.ioloop._asyncio_event_loop.run_until_complete(get_msg(future_msg))
|
|
assert self.session is not None
|
|
ident, smsg = self.session.feed_identities(msg_list)
|
|
msg = self.session.deserialize(smsg)
|
|
# let client inspect messages
|
|
if self._inspect:
|
|
self._inspect(msg)
|
|
self.call_handlers(msg)
|
|
|
|
def call_handlers(self, msg: Dict[str, Any]) -> None:
|
|
"""This method is called in the ioloop thread when a message arrives.
|
|
|
|
Subclasses should override this method to handle incoming messages.
|
|
It is important to remember that this method is called in the thread
|
|
so that some logic must be done to ensure that the application level
|
|
handlers are called in the application thread.
|
|
"""
|
|
pass
|
|
|
|
def process_events(self) -> None:
|
|
"""Subclasses should override this with a method
|
|
processing any pending GUI events.
|
|
"""
|
|
pass
|
|
|
|
def flush(self, timeout: float = 1.0) -> None:
|
|
"""Immediately processes all pending messages on this channel.
|
|
|
|
This is only used for the IOPub channel.
|
|
|
|
Callers should use this method to ensure that :meth:`call_handlers`
|
|
has been called for all messages that have been received on the
|
|
0MQ SUB socket of this channel.
|
|
|
|
This method is thread safe.
|
|
|
|
Parameters
|
|
----------
|
|
timeout : float, optional
|
|
The maximum amount of time to spend flushing, in seconds. The
|
|
default is one second.
|
|
"""
|
|
# We do the IOLoop callback process twice to ensure that the IOLoop
|
|
# gets to perform at least one full poll.
|
|
stop_time = time.time() + timeout
|
|
assert self.ioloop is not None
|
|
for _ in range(2):
|
|
self._flushed = False
|
|
self.ioloop.add_callback(self._flush)
|
|
while not self._flushed and time.time() < stop_time:
|
|
time.sleep(0.01)
|
|
|
|
def _flush(self) -> None:
|
|
"""Callback for :method:`self.flush`."""
|
|
assert self.stream is not None
|
|
self.stream.flush()
|
|
self._flushed = True
|
|
|
|
|
|
class IOLoopThread(Thread):
|
|
"""Run a pyzmq ioloop in a thread to send and receive messages"""
|
|
|
|
_exiting = False
|
|
ioloop = None
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
self.daemon = True
|
|
|
|
@staticmethod
|
|
@atexit.register
|
|
def _notice_exit() -> None:
|
|
# Class definitions can be torn down during interpreter shutdown.
|
|
# We only need to set _exiting flag if this hasn't happened.
|
|
if IOLoopThread is not None:
|
|
IOLoopThread._exiting = True
|
|
|
|
def start(self) -> None:
|
|
"""Start the IOLoop thread
|
|
|
|
Don't return until self.ioloop is defined,
|
|
which is created in the thread
|
|
"""
|
|
self._start_event = Event()
|
|
Thread.start(self)
|
|
self._start_event.wait()
|
|
|
|
def run(self) -> None:
|
|
"""Run my loop, ignoring EINTR events in the poller"""
|
|
loop = asyncio.new_event_loop()
|
|
asyncio.set_event_loop(loop)
|
|
nest_asyncio.apply(loop)
|
|
self.ioloop = ioloop.IOLoop()
|
|
self.ioloop._asyncio_event_loop = loop
|
|
# signal that self.ioloop is defined
|
|
self._start_event.set()
|
|
while True:
|
|
try:
|
|
self.ioloop.start()
|
|
except ZMQError as e:
|
|
if e.errno == errno.EINTR:
|
|
continue
|
|
else:
|
|
raise
|
|
except Exception:
|
|
if self._exiting:
|
|
break
|
|
else:
|
|
raise
|
|
else:
|
|
break
|
|
|
|
def stop(self) -> None:
|
|
"""Stop the channel's event loop and join its thread.
|
|
|
|
This calls :meth:`~threading.Thread.join` and returns when the thread
|
|
terminates. :class:`RuntimeError` will be raised if
|
|
:meth:`~threading.Thread.start` is called again.
|
|
"""
|
|
if self.ioloop is not None:
|
|
self.ioloop.add_callback(self.ioloop.stop)
|
|
self.join()
|
|
self.close()
|
|
self.ioloop = None
|
|
|
|
def __del__(self):
|
|
self.close()
|
|
|
|
def close(self) -> None:
|
|
if self.ioloop is not None:
|
|
try:
|
|
self.ioloop.close(all_fds=True)
|
|
except Exception:
|
|
pass
|
|
|
|
|
|
class ThreadedKernelClient(KernelClient):
|
|
"""A KernelClient that provides thread-safe sockets with async callbacks on message replies."""
|
|
|
|
@property
|
|
def ioloop(self):
|
|
return self.ioloop_thread.ioloop
|
|
|
|
ioloop_thread = Instance(IOLoopThread, allow_none=True)
|
|
|
|
def start_channels(
|
|
self,
|
|
shell: bool = True,
|
|
iopub: bool = True,
|
|
stdin: bool = True,
|
|
hb: bool = True,
|
|
control: bool = True,
|
|
) -> None:
|
|
self.ioloop_thread = IOLoopThread()
|
|
self.ioloop_thread.start()
|
|
|
|
if shell:
|
|
self.shell_channel._inspect = self._check_kernel_info_reply
|
|
|
|
super().start_channels(shell, iopub, stdin, hb, control)
|
|
|
|
def _check_kernel_info_reply(self, msg: Dict[str, Any]) -> None:
|
|
"""This is run in the ioloop thread when the kernel info reply is received"""
|
|
if msg["msg_type"] == "kernel_info_reply":
|
|
self._handle_kernel_info_reply(msg)
|
|
self.shell_channel._inspect = None
|
|
|
|
def stop_channels(self) -> None:
|
|
super().stop_channels()
|
|
if self.ioloop_thread.is_alive():
|
|
self.ioloop_thread.stop()
|
|
|
|
iopub_channel_class = Type(ThreadedZMQSocketChannel)
|
|
shell_channel_class = Type(ThreadedZMQSocketChannel)
|
|
stdin_channel_class = Type(ThreadedZMQSocketChannel)
|
|
hb_channel_class = Type(HBChannel)
|
|
control_channel_class = Type(ThreadedZMQSocketChannel)
|
|
|
|
def is_alive(self) -> bool:
|
|
"""Is the kernel process still running?"""
|
|
if self._hb_channel is not None:
|
|
# We don't have access to the KernelManager,
|
|
# so we use the heartbeat.
|
|
return self._hb_channel.is_beating()
|
|
# no heartbeat and not local, we can't tell if it's running,
|
|
# so naively return True
|
|
return True
|