|
|
"""Base classes to manage the interaction with a running kernel.
|
|
|
|
|
|
TODO
|
|
|
* Create logger to handle debugging and console messages.
|
|
|
"""
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Copyright (C) 2008-2010 The IPython Development Team
|
|
|
#
|
|
|
# Distributed under the terms of the BSD License. The full license is in
|
|
|
# the file COPYING, distributed as part of this software.
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Imports
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
# Standard library imports.
|
|
|
from Queue import Queue, Empty
|
|
|
from subprocess import Popen
|
|
|
import signal
|
|
|
import sys
|
|
|
from threading import Thread
|
|
|
import time
|
|
|
|
|
|
# System library imports.
|
|
|
import zmq
|
|
|
from zmq import POLLIN, POLLOUT, POLLERR
|
|
|
from zmq.eventloop import ioloop
|
|
|
|
|
|
# Local imports.
|
|
|
from IPython.utils import io
|
|
|
from IPython.utils.traitlets import HasTraits, Any, Instance, Type, TCPAddress
|
|
|
from session import Session
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Constants and exceptions
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
LOCALHOST = '127.0.0.1'
|
|
|
|
|
|
class InvalidPortNumber(Exception):
|
|
|
pass
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Utility functions
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
# some utilities to validate message structure, these might get moved elsewhere
|
|
|
# if they prove to have more generic utility
|
|
|
|
|
|
def validate_string_list(lst):
|
|
|
"""Validate that the input is a list of strings.
|
|
|
|
|
|
Raises ValueError if not."""
|
|
|
if not isinstance(lst, list):
|
|
|
raise ValueError('input %r must be a list' % lst)
|
|
|
for x in lst:
|
|
|
if not isinstance(x, basestring):
|
|
|
raise ValueError('element %r in list must be a string' % x)
|
|
|
|
|
|
|
|
|
def validate_string_dict(dct):
|
|
|
"""Validate that the input is a dict with string keys and values.
|
|
|
|
|
|
Raises ValueError if not."""
|
|
|
for k,v in dct.iteritems():
|
|
|
if not isinstance(k, basestring):
|
|
|
raise ValueError('key %r in dict must be a string' % k)
|
|
|
if not isinstance(v, basestring):
|
|
|
raise ValueError('value %r in dict must be a string' % v)
|
|
|
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# ZMQ Socket Channel classes
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
class ZmqSocketChannel(Thread):
|
|
|
"""The base class for the channels that use ZMQ sockets.
|
|
|
"""
|
|
|
context = None
|
|
|
session = None
|
|
|
socket = None
|
|
|
ioloop = None
|
|
|
iostate = None
|
|
|
_address = None
|
|
|
|
|
|
def __init__(self, context, session, address):
|
|
|
"""Create a channel
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
context : :class:`zmq.Context`
|
|
|
The ZMQ context to use.
|
|
|
session : :class:`session.Session`
|
|
|
The session to use.
|
|
|
address : tuple
|
|
|
Standard (ip, port) tuple that the kernel is listening on.
|
|
|
"""
|
|
|
super(ZmqSocketChannel, self).__init__()
|
|
|
self.daemon = True
|
|
|
|
|
|
self.context = context
|
|
|
self.session = session
|
|
|
if address[1] == 0:
|
|
|
message = 'The port number for a channel cannot be 0.'
|
|
|
raise InvalidPortNumber(message)
|
|
|
self._address = address
|
|
|
|
|
|
def stop(self):
|
|
|
"""Stop the channel's activity.
|
|
|
|
|
|
This calls :method:`Thread.join` and returns when the thread
|
|
|
terminates. :class:`RuntimeError` will be raised if
|
|
|
:method:`self.start` is called again.
|
|
|
"""
|
|
|
self.join()
|
|
|
|
|
|
@property
|
|
|
def address(self):
|
|
|
"""Get the channel's address as an (ip, port) tuple.
|
|
|
|
|
|
By the default, the address is (localhost, 0), where 0 means a random
|
|
|
port.
|
|
|
"""
|
|
|
return self._address
|
|
|
|
|
|
def add_io_state(self, state):
|
|
|
"""Add IO state to the eventloop.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
state : zmq.POLLIN|zmq.POLLOUT|zmq.POLLERR
|
|
|
The IO state flag to set.
|
|
|
|
|
|
This is thread safe as it uses the thread safe IOLoop.add_callback.
|
|
|
"""
|
|
|
def add_io_state_callback():
|
|
|
if not self.iostate & state:
|
|
|
self.iostate = self.iostate | state
|
|
|
self.ioloop.update_handler(self.socket, self.iostate)
|
|
|
self.ioloop.add_callback(add_io_state_callback)
|
|
|
|
|
|
def drop_io_state(self, state):
|
|
|
"""Drop IO state from the eventloop.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
state : zmq.POLLIN|zmq.POLLOUT|zmq.POLLERR
|
|
|
The IO state flag to set.
|
|
|
|
|
|
This is thread safe as it uses the thread safe IOLoop.add_callback.
|
|
|
"""
|
|
|
def drop_io_state_callback():
|
|
|
if self.iostate & state:
|
|
|
self.iostate = self.iostate & (~state)
|
|
|
self.ioloop.update_handler(self.socket, self.iostate)
|
|
|
self.ioloop.add_callback(drop_io_state_callback)
|
|
|
|
|
|
|
|
|
class XReqSocketChannel(ZmqSocketChannel):
|
|
|
"""The XREQ channel for issues request/replies to the kernel.
|
|
|
"""
|
|
|
|
|
|
command_queue = None
|
|
|
|
|
|
def __init__(self, context, session, address):
|
|
|
super(XReqSocketChannel, self).__init__(context, session, address)
|
|
|
self.command_queue = Queue()
|
|
|
self.ioloop = ioloop.IOLoop()
|
|
|
|
|
|
def run(self):
|
|
|
"""The thread's main activity. Call start() instead."""
|
|
|
self.socket = self.context.socket(zmq.XREQ)
|
|
|
self.socket.setsockopt(zmq.IDENTITY, self.session.session)
|
|
|
self.socket.connect('tcp://%s:%i' % self.address)
|
|
|
self.iostate = POLLERR|POLLIN
|
|
|
self.ioloop.add_handler(self.socket, self._handle_events,
|
|
|
self.iostate)
|
|
|
self.ioloop.start()
|
|
|
|
|
|
def stop(self):
|
|
|
self.ioloop.stop()
|
|
|
super(XReqSocketChannel, self).stop()
|
|
|
|
|
|
def call_handlers(self, msg):
|
|
|
"""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 leve
|
|
|
handlers are called in the application thread.
|
|
|
"""
|
|
|
raise NotImplementedError('call_handlers must be defined in a subclass.')
|
|
|
|
|
|
def execute(self, code, silent=False,
|
|
|
user_variables=None, user_expressions=None):
|
|
|
"""Execute code in the kernel.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
code : str
|
|
|
A string of Python code.
|
|
|
|
|
|
silent : bool, optional (default False)
|
|
|
If set, the kernel will execute the code as quietly possible.
|
|
|
|
|
|
user_variables : list, optional
|
|
|
A list of variable names to pull from the user's namespace. They
|
|
|
will come back as a dict with these names as keys and their
|
|
|
:func:`repr` as values.
|
|
|
|
|
|
user_expressions : dict, optional
|
|
|
A dict with string keys and to pull from the user's
|
|
|
namespace. They will come back as a dict with these names as keys
|
|
|
and their :func:`repr` as values.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
The msg_id of the message sent.
|
|
|
"""
|
|
|
if user_variables is None:
|
|
|
user_variables = []
|
|
|
if user_expressions is None:
|
|
|
user_expressions = {}
|
|
|
|
|
|
# Don't waste network traffic if inputs are invalid
|
|
|
if not isinstance(code, basestring):
|
|
|
raise ValueError('code %r must be a string' % code)
|
|
|
validate_string_list(user_variables)
|
|
|
validate_string_dict(user_expressions)
|
|
|
|
|
|
# Create class for content/msg creation. Related to, but possibly
|
|
|
# not in Session.
|
|
|
content = dict(code=code, silent=silent,
|
|
|
user_variables=user_variables,
|
|
|
user_expressions=user_expressions)
|
|
|
msg = self.session.msg('execute_request', content)
|
|
|
self._queue_request(msg)
|
|
|
return msg['header']['msg_id']
|
|
|
|
|
|
def complete(self, text, line, cursor_pos, block=None):
|
|
|
"""Tab complete text in the kernel's namespace.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
text : str
|
|
|
The text to complete.
|
|
|
line : str
|
|
|
The full line of text that is the surrounding context for the
|
|
|
text to complete.
|
|
|
cursor_pos : int
|
|
|
The position of the cursor in the line where the completion was
|
|
|
requested.
|
|
|
block : str, optional
|
|
|
The full block of code in which the completion is being requested.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
The msg_id of the message sent.
|
|
|
"""
|
|
|
content = dict(text=text, line=line, block=block, cursor_pos=cursor_pos)
|
|
|
msg = self.session.msg('complete_request', content)
|
|
|
self._queue_request(msg)
|
|
|
return msg['header']['msg_id']
|
|
|
|
|
|
def object_info(self, oname):
|
|
|
"""Get metadata information about an object.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
oname : str
|
|
|
A string specifying the object name.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
The msg_id of the message sent.
|
|
|
"""
|
|
|
content = dict(oname=oname)
|
|
|
msg = self.session.msg('object_info_request', content)
|
|
|
self._queue_request(msg)
|
|
|
return msg['header']['msg_id']
|
|
|
|
|
|
def history(self, index=None, raw=False, output=True):
|
|
|
"""Get the history list.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
index : n or (n1, n2) or None
|
|
|
If n, then the last entries. If a tuple, then all in
|
|
|
range(n1, n2). If None, then all entries. Raises IndexError if
|
|
|
the format of index is incorrect.
|
|
|
raw : bool
|
|
|
If True, return the raw input.
|
|
|
output : bool
|
|
|
If True, then return the output as well.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
The msg_id of the message sent.
|
|
|
"""
|
|
|
content = dict(index=index, raw=raw, output=output)
|
|
|
msg = self.session.msg('history_request', content)
|
|
|
self._queue_request(msg)
|
|
|
return msg['header']['msg_id']
|
|
|
|
|
|
def shutdown(self):
|
|
|
"""Request an immediate kernel shutdown.
|
|
|
|
|
|
Upon receipt of the (empty) reply, client code can safely assume that
|
|
|
the kernel has shut down and it's safe to forcefully terminate it if
|
|
|
it's still alive.
|
|
|
|
|
|
The kernel will send the reply via a function registered with Python's
|
|
|
atexit module, ensuring it's truly done as the kernel is done with all
|
|
|
normal operation.
|
|
|
"""
|
|
|
# Send quit message to kernel. Once we implement kernel-side setattr,
|
|
|
# this should probably be done that way, but for now this will do.
|
|
|
msg = self.session.msg('shutdown_request', {})
|
|
|
self._queue_request(msg)
|
|
|
return msg['header']['msg_id']
|
|
|
|
|
|
def _handle_events(self, socket, events):
|
|
|
if events & POLLERR:
|
|
|
self._handle_err()
|
|
|
if events & POLLOUT:
|
|
|
self._handle_send()
|
|
|
if events & POLLIN:
|
|
|
self._handle_recv()
|
|
|
|
|
|
def _handle_recv(self):
|
|
|
msg = self.socket.recv_json()
|
|
|
self.call_handlers(msg)
|
|
|
|
|
|
def _handle_send(self):
|
|
|
try:
|
|
|
msg = self.command_queue.get(False)
|
|
|
except Empty:
|
|
|
pass
|
|
|
else:
|
|
|
self.socket.send_json(msg)
|
|
|
if self.command_queue.empty():
|
|
|
self.drop_io_state(POLLOUT)
|
|
|
|
|
|
def _handle_err(self):
|
|
|
# We don't want to let this go silently, so eventually we should log.
|
|
|
raise zmq.ZMQError()
|
|
|
|
|
|
def _queue_request(self, msg):
|
|
|
self.command_queue.put(msg)
|
|
|
self.add_io_state(POLLOUT)
|
|
|
|
|
|
|
|
|
class SubSocketChannel(ZmqSocketChannel):
|
|
|
"""The SUB channel which listens for messages that the kernel publishes.
|
|
|
"""
|
|
|
|
|
|
def __init__(self, context, session, address):
|
|
|
super(SubSocketChannel, self).__init__(context, session, address)
|
|
|
self.ioloop = ioloop.IOLoop()
|
|
|
|
|
|
def run(self):
|
|
|
"""The thread's main activity. Call start() instead."""
|
|
|
self.socket = self.context.socket(zmq.SUB)
|
|
|
self.socket.setsockopt(zmq.SUBSCRIBE,'')
|
|
|
self.socket.setsockopt(zmq.IDENTITY, self.session.session)
|
|
|
self.socket.connect('tcp://%s:%i' % self.address)
|
|
|
self.iostate = POLLIN|POLLERR
|
|
|
self.ioloop.add_handler(self.socket, self._handle_events,
|
|
|
self.iostate)
|
|
|
self.ioloop.start()
|
|
|
|
|
|
def stop(self):
|
|
|
self.ioloop.stop()
|
|
|
super(SubSocketChannel, self).stop()
|
|
|
|
|
|
def call_handlers(self, msg):
|
|
|
"""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 leve
|
|
|
handlers are called in the application thread.
|
|
|
"""
|
|
|
raise NotImplementedError('call_handlers must be defined in a subclass.')
|
|
|
|
|
|
def flush(self, timeout=1.0):
|
|
|
"""Immediately processes all pending messages on the SUB channel.
|
|
|
|
|
|
Callers should use this method to ensure that :method:`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
|
|
|
for i in xrange(2):
|
|
|
self._flushed = False
|
|
|
self.ioloop.add_callback(self._flush)
|
|
|
while not self._flushed and time.time() < stop_time:
|
|
|
time.sleep(0.01)
|
|
|
|
|
|
def _handle_events(self, socket, events):
|
|
|
# Turn on and off POLLOUT depending on if we have made a request
|
|
|
if events & POLLERR:
|
|
|
self._handle_err()
|
|
|
if events & POLLIN:
|
|
|
self._handle_recv()
|
|
|
|
|
|
def _handle_err(self):
|
|
|
# We don't want to let this go silently, so eventually we should log.
|
|
|
raise zmq.ZMQError()
|
|
|
|
|
|
def _handle_recv(self):
|
|
|
# Get all of the messages we can
|
|
|
while True:
|
|
|
try:
|
|
|
msg = self.socket.recv_json(zmq.NOBLOCK)
|
|
|
except zmq.ZMQError:
|
|
|
# Check the errno?
|
|
|
# Will this trigger POLLERR?
|
|
|
break
|
|
|
else:
|
|
|
self.call_handlers(msg)
|
|
|
|
|
|
def _flush(self):
|
|
|
"""Callback for :method:`self.flush`."""
|
|
|
self._flushed = True
|
|
|
|
|
|
|
|
|
class RepSocketChannel(ZmqSocketChannel):
|
|
|
"""A reply channel to handle raw_input requests that the kernel makes."""
|
|
|
|
|
|
msg_queue = None
|
|
|
|
|
|
def __init__(self, context, session, address):
|
|
|
super(RepSocketChannel, self).__init__(context, session, address)
|
|
|
self.ioloop = ioloop.IOLoop()
|
|
|
self.msg_queue = Queue()
|
|
|
|
|
|
def run(self):
|
|
|
"""The thread's main activity. Call start() instead."""
|
|
|
self.socket = self.context.socket(zmq.XREQ)
|
|
|
self.socket.setsockopt(zmq.IDENTITY, self.session.session)
|
|
|
self.socket.connect('tcp://%s:%i' % self.address)
|
|
|
self.iostate = POLLERR|POLLIN
|
|
|
self.ioloop.add_handler(self.socket, self._handle_events,
|
|
|
self.iostate)
|
|
|
self.ioloop.start()
|
|
|
|
|
|
def stop(self):
|
|
|
self.ioloop.stop()
|
|
|
super(RepSocketChannel, self).stop()
|
|
|
|
|
|
def call_handlers(self, msg):
|
|
|
"""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 leve
|
|
|
handlers are called in the application thread.
|
|
|
"""
|
|
|
raise NotImplementedError('call_handlers must be defined in a subclass.')
|
|
|
|
|
|
def input(self, string):
|
|
|
"""Send a string of raw input to the kernel."""
|
|
|
content = dict(value=string)
|
|
|
msg = self.session.msg('input_reply', content)
|
|
|
self._queue_reply(msg)
|
|
|
|
|
|
def _handle_events(self, socket, events):
|
|
|
if events & POLLERR:
|
|
|
self._handle_err()
|
|
|
if events & POLLOUT:
|
|
|
self._handle_send()
|
|
|
if events & POLLIN:
|
|
|
self._handle_recv()
|
|
|
|
|
|
def _handle_recv(self):
|
|
|
msg = self.socket.recv_json()
|
|
|
self.call_handlers(msg)
|
|
|
|
|
|
def _handle_send(self):
|
|
|
try:
|
|
|
msg = self.msg_queue.get(False)
|
|
|
except Empty:
|
|
|
pass
|
|
|
else:
|
|
|
self.socket.send_json(msg)
|
|
|
if self.msg_queue.empty():
|
|
|
self.drop_io_state(POLLOUT)
|
|
|
|
|
|
def _handle_err(self):
|
|
|
# We don't want to let this go silently, so eventually we should log.
|
|
|
raise zmq.ZMQError()
|
|
|
|
|
|
def _queue_reply(self, msg):
|
|
|
self.msg_queue.put(msg)
|
|
|
self.add_io_state(POLLOUT)
|
|
|
|
|
|
|
|
|
class HBSocketChannel(ZmqSocketChannel):
|
|
|
"""The heartbeat channel which monitors the kernel heartbeat.
|
|
|
|
|
|
Note that the heartbeat channel is paused by default. As long as you start
|
|
|
this channel, the kernel manager will ensure that it is paused and un-paused
|
|
|
as appropriate.
|
|
|
"""
|
|
|
|
|
|
time_to_dead = 3.0
|
|
|
socket = None
|
|
|
poller = None
|
|
|
_running = None
|
|
|
_pause = None
|
|
|
|
|
|
def __init__(self, context, session, address):
|
|
|
super(HBSocketChannel, self).__init__(context, session, address)
|
|
|
self._running = False
|
|
|
self._pause = True
|
|
|
|
|
|
def _create_socket(self):
|
|
|
self.socket = self.context.socket(zmq.REQ)
|
|
|
self.socket.setsockopt(zmq.IDENTITY, self.session.session)
|
|
|
self.socket.connect('tcp://%s:%i' % self.address)
|
|
|
self.poller = zmq.Poller()
|
|
|
self.poller.register(self.socket, zmq.POLLIN)
|
|
|
|
|
|
def run(self):
|
|
|
"""The thread's main activity. Call start() instead."""
|
|
|
self._create_socket()
|
|
|
self._running = True
|
|
|
while self._running:
|
|
|
if self._pause:
|
|
|
time.sleep(self.time_to_dead)
|
|
|
else:
|
|
|
since_last_heartbeat = 0.0
|
|
|
request_time = time.time()
|
|
|
try:
|
|
|
#io.rprint('Ping from HB channel') # dbg
|
|
|
self.socket.send_json('ping')
|
|
|
except zmq.ZMQError, e:
|
|
|
#io.rprint('*** HB Error:', e) # dbg
|
|
|
if e.errno == zmq.EFSM:
|
|
|
#io.rprint('sleep...', self.time_to_dead) # dbg
|
|
|
time.sleep(self.time_to_dead)
|
|
|
self._create_socket()
|
|
|
else:
|
|
|
raise
|
|
|
else:
|
|
|
while True:
|
|
|
try:
|
|
|
self.socket.recv_json(zmq.NOBLOCK)
|
|
|
except zmq.ZMQError, e:
|
|
|
#io.rprint('*** HB Error 2:', e) # dbg
|
|
|
if e.errno == zmq.EAGAIN:
|
|
|
before_poll = time.time()
|
|
|
until_dead = self.time_to_dead - (before_poll -
|
|
|
request_time)
|
|
|
|
|
|
# When the return value of poll() is an empty
|
|
|
# list, that is when things have gone wrong
|
|
|
# (zeromq bug). As long as it is not an empty
|
|
|
# list, poll is working correctly even if it
|
|
|
# returns quickly. Note: poll timeout is in
|
|
|
# milliseconds.
|
|
|
self.poller.poll(1000*until_dead)
|
|
|
|
|
|
since_last_heartbeat = time.time()-request_time
|
|
|
if since_last_heartbeat > self.time_to_dead:
|
|
|
self.call_handlers(since_last_heartbeat)
|
|
|
break
|
|
|
else:
|
|
|
# FIXME: We should probably log this instead.
|
|
|
raise
|
|
|
else:
|
|
|
until_dead = self.time_to_dead - (time.time() -
|
|
|
request_time)
|
|
|
if until_dead > 0.0:
|
|
|
#io.rprint('sleep...', self.time_to_dead) # dbg
|
|
|
time.sleep(until_dead)
|
|
|
break
|
|
|
|
|
|
def pause(self):
|
|
|
"""Pause the heartbeat."""
|
|
|
self._pause = True
|
|
|
|
|
|
def unpause(self):
|
|
|
"""Unpause the heartbeat."""
|
|
|
self._pause = False
|
|
|
|
|
|
def is_beating(self):
|
|
|
"""Is the heartbeat running and not paused."""
|
|
|
if self.is_alive() and not self._pause:
|
|
|
return True
|
|
|
else:
|
|
|
return False
|
|
|
|
|
|
def stop(self):
|
|
|
self._running = False
|
|
|
super(HBSocketChannel, self).stop()
|
|
|
|
|
|
def call_handlers(self, since_last_heartbeat):
|
|
|
"""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 leve
|
|
|
handlers are called in the application thread.
|
|
|
"""
|
|
|
raise NotImplementedError('call_handlers must be defined in a subclass.')
|
|
|
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Main kernel manager class
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
class KernelManager(HasTraits):
|
|
|
""" Manages a kernel for a frontend.
|
|
|
|
|
|
The SUB channel is for the frontend to receive messages published by the
|
|
|
kernel.
|
|
|
|
|
|
The REQ channel is for the frontend to make requests of the kernel.
|
|
|
|
|
|
The REP channel is for the kernel to request stdin (raw_input) from the
|
|
|
frontend.
|
|
|
"""
|
|
|
# The PyZMQ Context to use for communication with the kernel.
|
|
|
context = Instance(zmq.Context,(),{})
|
|
|
|
|
|
# The Session to use for communication with the kernel.
|
|
|
session = Instance(Session,(),{})
|
|
|
|
|
|
# The kernel process with which the KernelManager is communicating.
|
|
|
kernel = Instance(Popen)
|
|
|
|
|
|
# The addresses for the communication channels.
|
|
|
xreq_address = TCPAddress((LOCALHOST, 0))
|
|
|
sub_address = TCPAddress((LOCALHOST, 0))
|
|
|
rep_address = TCPAddress((LOCALHOST, 0))
|
|
|
hb_address = TCPAddress((LOCALHOST, 0))
|
|
|
|
|
|
# The classes to use for the various channels.
|
|
|
xreq_channel_class = Type(XReqSocketChannel)
|
|
|
sub_channel_class = Type(SubSocketChannel)
|
|
|
rep_channel_class = Type(RepSocketChannel)
|
|
|
hb_channel_class = Type(HBSocketChannel)
|
|
|
|
|
|
# Protected traits.
|
|
|
_launch_args = Any
|
|
|
_xreq_channel = Any
|
|
|
_sub_channel = Any
|
|
|
_rep_channel = Any
|
|
|
_hb_channel = Any
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# Channel management methods:
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
def start_channels(self, xreq=True, sub=True, rep=True, hb=True):
|
|
|
"""Starts the channels for this kernel.
|
|
|
|
|
|
This will create the channels if they do not exist and then start
|
|
|
them. If port numbers of 0 are being used (random ports) then you
|
|
|
must first call :method:`start_kernel`. If the channels have been
|
|
|
stopped and you call this, :class:`RuntimeError` will be raised.
|
|
|
"""
|
|
|
if xreq:
|
|
|
self.xreq_channel.start()
|
|
|
if sub:
|
|
|
self.sub_channel.start()
|
|
|
if rep:
|
|
|
self.rep_channel.start()
|
|
|
if hb:
|
|
|
self.hb_channel.start()
|
|
|
|
|
|
def stop_channels(self):
|
|
|
"""Stops all the running channels for this kernel.
|
|
|
"""
|
|
|
if self.xreq_channel.is_alive():
|
|
|
self.xreq_channel.stop()
|
|
|
if self.sub_channel.is_alive():
|
|
|
self.sub_channel.stop()
|
|
|
if self.rep_channel.is_alive():
|
|
|
self.rep_channel.stop()
|
|
|
if self.hb_channel.is_alive():
|
|
|
self.hb_channel.stop()
|
|
|
|
|
|
@property
|
|
|
def channels_running(self):
|
|
|
"""Are any of the channels created and running?"""
|
|
|
return (self.xreq_channel.is_alive() or self.sub_channel.is_alive() or
|
|
|
self.rep_channel.is_alive() or self.hb_channel.is_alive())
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# Kernel process management methods:
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
def start_kernel(self, **kw):
|
|
|
"""Starts a kernel process and configures the manager to use it.
|
|
|
|
|
|
If random ports (port=0) are being used, this method must be called
|
|
|
before the channels are created.
|
|
|
|
|
|
Parameters:
|
|
|
-----------
|
|
|
ipython : bool, optional (default True)
|
|
|
Whether to use an IPython kernel instead of a plain Python kernel.
|
|
|
"""
|
|
|
xreq, sub, rep, hb = self.xreq_address, self.sub_address, \
|
|
|
self.rep_address, self.hb_address
|
|
|
if xreq[0] != LOCALHOST or sub[0] != LOCALHOST or \
|
|
|
rep[0] != LOCALHOST or hb[0] != LOCALHOST:
|
|
|
raise RuntimeError("Can only launch a kernel on localhost."
|
|
|
"Make sure that the '*_address' attributes are "
|
|
|
"configured properly.")
|
|
|
|
|
|
self._launch_args = kw.copy()
|
|
|
if kw.pop('ipython', True):
|
|
|
from ipkernel import launch_kernel
|
|
|
else:
|
|
|
from pykernel import launch_kernel
|
|
|
self.kernel, xrep, pub, req, hb = launch_kernel(
|
|
|
xrep_port=xreq[1], pub_port=sub[1],
|
|
|
req_port=rep[1], hb_port=hb[1], **kw)
|
|
|
self.xreq_address = (LOCALHOST, xrep)
|
|
|
self.sub_address = (LOCALHOST, pub)
|
|
|
self.rep_address = (LOCALHOST, req)
|
|
|
self.hb_address = (LOCALHOST, hb)
|
|
|
|
|
|
def shutdown_kernel(self):
|
|
|
""" Attempts to the stop the kernel process cleanly. If the kernel
|
|
|
cannot be stopped, it is killed, if possible.
|
|
|
"""
|
|
|
# FIXME: Shutdown does not work on Windows due to ZMQ errors!
|
|
|
if sys.platform == 'win32':
|
|
|
self.kill_kernel()
|
|
|
return
|
|
|
|
|
|
# Pause the heart beat channel if it exists.
|
|
|
if self._hb_channel is not None:
|
|
|
self._hb_channel.pause()
|
|
|
|
|
|
# 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.xreq_channel.shutdown()
|
|
|
for i in range(10):
|
|
|
if self.is_alive:
|
|
|
time.sleep(0.1)
|
|
|
else:
|
|
|
break
|
|
|
else:
|
|
|
# OK, we've waited long enough.
|
|
|
if self.has_kernel:
|
|
|
self.kill_kernel()
|
|
|
|
|
|
def restart_kernel(self, now=False):
|
|
|
"""Restarts a kernel with the same 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.
|
|
|
|
|
|
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.
|
|
|
"""
|
|
|
if self._launch_args is None:
|
|
|
raise RuntimeError("Cannot restart the kernel. "
|
|
|
"No previous call to 'start_kernel'.")
|
|
|
else:
|
|
|
if self.has_kernel:
|
|
|
if now:
|
|
|
self.kill_kernel()
|
|
|
else:
|
|
|
self.shutdown_kernel()
|
|
|
self.start_kernel(**self._launch_args)
|
|
|
|
|
|
# FIXME: Messages get dropped in Windows due to probable ZMQ bug
|
|
|
# unless there is some delay here.
|
|
|
if sys.platform == 'win32':
|
|
|
time.sleep(0.2)
|
|
|
|
|
|
@property
|
|
|
def has_kernel(self):
|
|
|
"""Returns whether a kernel process has been specified for the kernel
|
|
|
manager.
|
|
|
"""
|
|
|
return self.kernel is not None
|
|
|
|
|
|
def kill_kernel(self):
|
|
|
""" Kill the running kernel. """
|
|
|
if self.has_kernel:
|
|
|
# Pause the heart beat channel if it exists.
|
|
|
if self._hb_channel is not None:
|
|
|
self._hb_channel.pause()
|
|
|
|
|
|
# Attempt to kill the kernel.
|
|
|
try:
|
|
|
self.kernel.kill()
|
|
|
except OSError, e:
|
|
|
# In Windows, we will get an Access Denied error if the process
|
|
|
# has already terminated. Ignore it.
|
|
|
if not (sys.platform == 'win32' and e.winerror == 5):
|
|
|
raise
|
|
|
self.kernel = None
|
|
|
else:
|
|
|
raise RuntimeError("Cannot kill kernel. No kernel is running!")
|
|
|
|
|
|
def interrupt_kernel(self):
|
|
|
""" Interrupts the kernel. Unlike ``signal_kernel``, this operation is
|
|
|
well supported on all platforms.
|
|
|
"""
|
|
|
if self.has_kernel:
|
|
|
if sys.platform == 'win32':
|
|
|
from 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!")
|
|
|
|
|
|
@property
|
|
|
def is_alive(self):
|
|
|
"""Is the kernel process still running?"""
|
|
|
# FIXME: not using a heartbeat means this method is broken for any
|
|
|
# remote kernel, it's only capable of handling local kernels.
|
|
|
if self.has_kernel:
|
|
|
if self.kernel.poll() is None:
|
|
|
return True
|
|
|
else:
|
|
|
return False
|
|
|
else:
|
|
|
# We didn't start the kernel with this KernelManager so we don't
|
|
|
# know if it is running. We should use a heartbeat for this case.
|
|
|
return True
|
|
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
# Channels used for communication with the kernel:
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
|
|
@property
|
|
|
def xreq_channel(self):
|
|
|
"""Get the REQ socket channel object to make requests of the kernel."""
|
|
|
if self._xreq_channel is None:
|
|
|
self._xreq_channel = self.xreq_channel_class(self.context,
|
|
|
self.session,
|
|
|
self.xreq_address)
|
|
|
return self._xreq_channel
|
|
|
|
|
|
@property
|
|
|
def sub_channel(self):
|
|
|
"""Get the SUB socket channel object."""
|
|
|
if self._sub_channel is None:
|
|
|
self._sub_channel = self.sub_channel_class(self.context,
|
|
|
self.session,
|
|
|
self.sub_address)
|
|
|
return self._sub_channel
|
|
|
|
|
|
@property
|
|
|
def rep_channel(self):
|
|
|
"""Get the REP socket channel object to handle stdin (raw_input)."""
|
|
|
if self._rep_channel is None:
|
|
|
self._rep_channel = self.rep_channel_class(self.context,
|
|
|
self.session,
|
|
|
self.rep_address)
|
|
|
return self._rep_channel
|
|
|
|
|
|
@property
|
|
|
def hb_channel(self):
|
|
|
"""Get the REP socket channel object to handle stdin (raw_input)."""
|
|
|
if self._hb_channel is None:
|
|
|
self._hb_channel = self.hb_channel_class(self.context,
|
|
|
self.session,
|
|
|
self.hb_address)
|
|
|
return self._hb_channel
|
|
|
|
