337 lines
12 KiB
Python
337 lines
12 KiB
Python
"""Implements a fully blocking kernel client.
|
|
|
|
Useful for test suites and blocking terminal interfaces.
|
|
"""
|
|
# Copyright (c) Jupyter Development Team.
|
|
# Distributed under the terms of the Modified BSD License.
|
|
|
|
from functools import partial
|
|
from getpass import getpass
|
|
from queue import Empty
|
|
import sys
|
|
import time
|
|
|
|
import zmq
|
|
|
|
from time import monotonic
|
|
from traitlets import Type
|
|
from jupyter_client.channels import HBChannel
|
|
from jupyter_client.client import KernelClient
|
|
from .channels import ZMQSocketChannel
|
|
|
|
|
|
def reqrep(meth, channel='shell'):
|
|
def wrapped(self, *args, **kwargs):
|
|
reply = kwargs.pop('reply', False)
|
|
timeout = kwargs.pop('timeout', None)
|
|
msg_id = meth(self, *args, **kwargs)
|
|
if not reply:
|
|
return msg_id
|
|
|
|
return self._recv_reply(msg_id, timeout=timeout, channel=channel)
|
|
|
|
if not meth.__doc__:
|
|
# python -OO removes docstrings,
|
|
# so don't bother building the wrapped docstring
|
|
return wrapped
|
|
|
|
basedoc, _ = meth.__doc__.split('Returns\n', 1)
|
|
parts = [basedoc.strip()]
|
|
if 'Parameters' not in basedoc:
|
|
parts.append("""
|
|
Parameters
|
|
----------
|
|
""")
|
|
parts.append("""
|
|
reply: bool (default: False)
|
|
Whether to wait for and return reply
|
|
timeout: float or None (default: None)
|
|
Timeout to use when waiting for a reply
|
|
|
|
Returns
|
|
-------
|
|
msg_id: str
|
|
The msg_id of the request sent, if reply=False (default)
|
|
reply: dict
|
|
The reply message for this request, if reply=True
|
|
""")
|
|
wrapped.__doc__ = '\n'.join(parts)
|
|
return wrapped
|
|
|
|
class BlockingKernelClient(KernelClient):
|
|
"""A KernelClient with blocking APIs
|
|
|
|
``get_[channel]_msg()`` methods wait for and return messages on channels,
|
|
raising :exc:`queue.Empty` if no message arrives within ``timeout`` seconds.
|
|
"""
|
|
|
|
def wait_for_ready(self, timeout=None):
|
|
"""Waits for a response when a client is blocked
|
|
|
|
- Sets future time for timeout
|
|
- Blocks on shell channel until a message is received
|
|
- Exit if the kernel has died
|
|
- If client times out before receiving a message from the kernel, send RuntimeError
|
|
- Flush the IOPub channel
|
|
"""
|
|
if timeout is None:
|
|
abs_timeout = float('inf')
|
|
else:
|
|
abs_timeout = time.time() + timeout
|
|
|
|
from ..manager import KernelManager
|
|
if not isinstance(self.parent, KernelManager):
|
|
# This Client was not created by a KernelManager,
|
|
# so wait for kernel to become responsive to heartbeats
|
|
# before checking for kernel_info reply
|
|
while not self.is_alive():
|
|
if time.time() > abs_timeout:
|
|
raise RuntimeError("Kernel didn't respond to heartbeats in %d seconds and timed out" % timeout)
|
|
time.sleep(0.2)
|
|
|
|
# Wait for kernel info reply on shell channel
|
|
while True:
|
|
try:
|
|
msg = self.shell_channel.get_msg(block=True, timeout=1)
|
|
except Empty:
|
|
pass
|
|
else:
|
|
if msg['msg_type'] == 'kernel_info_reply':
|
|
self._handle_kernel_info_reply(msg)
|
|
break
|
|
|
|
if not self.is_alive():
|
|
raise RuntimeError('Kernel died before replying to kernel_info')
|
|
|
|
# Check if current time is ready check time plus timeout
|
|
if time.time() > abs_timeout:
|
|
raise RuntimeError("Kernel didn't respond in %d seconds" % timeout)
|
|
|
|
# Flush IOPub channel
|
|
while True:
|
|
try:
|
|
msg = self.iopub_channel.get_msg(block=True, timeout=0.2)
|
|
except Empty:
|
|
break
|
|
|
|
# The classes to use for the various channels
|
|
shell_channel_class = Type(ZMQSocketChannel)
|
|
iopub_channel_class = Type(ZMQSocketChannel)
|
|
stdin_channel_class = Type(ZMQSocketChannel)
|
|
hb_channel_class = Type(HBChannel)
|
|
control_channel_class = Type(ZMQSocketChannel)
|
|
|
|
|
|
def _recv_reply(self, msg_id, timeout=None, channel='shell'):
|
|
"""Receive and return the reply for a given request"""
|
|
if timeout is not None:
|
|
deadline = monotonic() + timeout
|
|
while True:
|
|
if timeout is not None:
|
|
timeout = max(0, deadline - monotonic())
|
|
try:
|
|
if channel == 'control':
|
|
reply = self.get_control_msg(timeout=timeout)
|
|
else:
|
|
reply = self.get_shell_msg(timeout=timeout)
|
|
except Empty as e:
|
|
raise TimeoutError("Timeout waiting for reply") from e
|
|
if reply['parent_header'].get('msg_id') != msg_id:
|
|
# not my reply, someone may have forgotten to retrieve theirs
|
|
continue
|
|
return reply
|
|
|
|
|
|
# replies come on the shell channel
|
|
execute = reqrep(KernelClient.execute)
|
|
history = reqrep(KernelClient.history)
|
|
complete = reqrep(KernelClient.complete)
|
|
inspect = reqrep(KernelClient.inspect)
|
|
kernel_info = reqrep(KernelClient.kernel_info)
|
|
comm_info = reqrep(KernelClient.comm_info)
|
|
|
|
# replies come on the control channel
|
|
shutdown = reqrep(KernelClient.shutdown, channel='control')
|
|
|
|
|
|
def _stdin_hook_default(self, msg):
|
|
"""Handle an input request"""
|
|
content = msg['content']
|
|
if content.get('password', False):
|
|
prompt = getpass
|
|
else:
|
|
prompt = input
|
|
|
|
try:
|
|
raw_data = prompt(content["prompt"])
|
|
except EOFError:
|
|
# turn EOFError into EOF character
|
|
raw_data = '\x04'
|
|
except KeyboardInterrupt:
|
|
sys.stdout.write('\n')
|
|
return
|
|
|
|
# only send stdin reply if there *was not* another request
|
|
# or execution finished while we were reading.
|
|
if not (self.stdin_channel.msg_ready() or self.shell_channel.msg_ready()):
|
|
self.input(raw_data)
|
|
|
|
def _output_hook_default(self, msg):
|
|
"""Default hook for redisplaying plain-text output"""
|
|
msg_type = msg['header']['msg_type']
|
|
content = msg['content']
|
|
if msg_type == 'stream':
|
|
stream = getattr(sys, content['name'])
|
|
stream.write(content['text'])
|
|
elif msg_type in ('display_data', 'execute_result'):
|
|
sys.stdout.write(content['data'].get('text/plain', ''))
|
|
elif msg_type == 'error':
|
|
print('\n'.join(content['traceback']), file=sys.stderr)
|
|
|
|
def _output_hook_kernel(self, session, socket, parent_header, msg):
|
|
"""Output hook when running inside an IPython kernel
|
|
|
|
adds rich output support.
|
|
"""
|
|
msg_type = msg['header']['msg_type']
|
|
if msg_type in ('display_data', 'execute_result', 'error'):
|
|
session.send(socket, msg_type, msg['content'], parent=parent_header)
|
|
else:
|
|
self._output_hook_default(msg)
|
|
|
|
def execute_interactive(self, code, silent=False, store_history=True,
|
|
user_expressions=None, allow_stdin=None, stop_on_error=True,
|
|
timeout=None, output_hook=None, stdin_hook=None,
|
|
):
|
|
"""Execute code in the kernel interactively
|
|
|
|
Output will be redisplayed, and stdin prompts will be relayed as well.
|
|
If an IPython kernel is detected, rich output will be displayed.
|
|
|
|
You can pass a custom output_hook callable that will be called
|
|
with every IOPub message that is produced instead of the default redisplay.
|
|
|
|
.. versionadded:: 5.0
|
|
|
|
Parameters
|
|
----------
|
|
code : str
|
|
A string of code in the kernel's language.
|
|
|
|
silent : bool, optional (default False)
|
|
If set, the kernel will execute the code as quietly possible, and
|
|
will force store_history to be False.
|
|
|
|
store_history : bool, optional (default True)
|
|
If set, the kernel will store command history. This is forced
|
|
to be False if silent is True.
|
|
|
|
user_expressions : dict, optional
|
|
A dict mapping names to expressions to be evaluated in the user's
|
|
dict. The expression values are returned as strings formatted using
|
|
:func:`repr`.
|
|
|
|
allow_stdin : bool, optional (default self.allow_stdin)
|
|
Flag for whether the kernel can send stdin requests to frontends.
|
|
|
|
Some frontends (e.g. the Notebook) do not support stdin requests.
|
|
If raw_input is called from code executed from such a frontend, a
|
|
StdinNotImplementedError will be raised.
|
|
|
|
stop_on_error: bool, optional (default True)
|
|
Flag whether to abort the execution queue, if an exception is encountered.
|
|
|
|
timeout: float or None (default: None)
|
|
Timeout to use when waiting for a reply
|
|
|
|
output_hook: callable(msg)
|
|
Function to be called with output messages.
|
|
If not specified, output will be redisplayed.
|
|
|
|
stdin_hook: callable(msg)
|
|
Function to be called with stdin_request messages.
|
|
If not specified, input/getpass will be called.
|
|
|
|
Returns
|
|
-------
|
|
reply: dict
|
|
The reply message for this request
|
|
"""
|
|
if not self.iopub_channel.is_alive():
|
|
raise RuntimeError("IOPub channel must be running to receive output")
|
|
if allow_stdin is None:
|
|
allow_stdin = self.allow_stdin
|
|
if allow_stdin and not self.stdin_channel.is_alive():
|
|
raise RuntimeError("stdin channel must be running to allow input")
|
|
msg_id = self.execute(code,
|
|
silent=silent,
|
|
store_history=store_history,
|
|
user_expressions=user_expressions,
|
|
allow_stdin=allow_stdin,
|
|
stop_on_error=stop_on_error,
|
|
)
|
|
if stdin_hook is None:
|
|
stdin_hook = self._stdin_hook_default
|
|
if output_hook is None:
|
|
# detect IPython kernel
|
|
if 'IPython' in sys.modules:
|
|
from IPython import get_ipython
|
|
ip = get_ipython()
|
|
in_kernel = getattr(ip, 'kernel', False)
|
|
if in_kernel:
|
|
output_hook = partial(
|
|
self._output_hook_kernel,
|
|
ip.display_pub.session,
|
|
ip.display_pub.pub_socket,
|
|
ip.display_pub.parent_header,
|
|
)
|
|
if output_hook is None:
|
|
# default: redisplay plain-text outputs
|
|
output_hook = self._output_hook_default
|
|
|
|
# set deadline based on timeout
|
|
if timeout is not None:
|
|
deadline = monotonic() + timeout
|
|
else:
|
|
timeout_ms = None
|
|
|
|
poller = zmq.Poller()
|
|
iopub_socket = self.iopub_channel.socket
|
|
poller.register(iopub_socket, zmq.POLLIN)
|
|
if allow_stdin:
|
|
stdin_socket = self.stdin_channel.socket
|
|
poller.register(stdin_socket, zmq.POLLIN)
|
|
else:
|
|
stdin_socket = None
|
|
|
|
# wait for output and redisplay it
|
|
while True:
|
|
if timeout is not None:
|
|
timeout = max(0, deadline - monotonic())
|
|
timeout_ms = 1e3 * timeout
|
|
events = dict(poller.poll(timeout_ms))
|
|
if not events:
|
|
raise TimeoutError("Timeout waiting for output")
|
|
if stdin_socket in events:
|
|
req = self.stdin_channel.get_msg(timeout=0)
|
|
stdin_hook(req)
|
|
continue
|
|
if iopub_socket not in events:
|
|
continue
|
|
|
|
msg = self.iopub_channel.get_msg(timeout=0)
|
|
|
|
if msg['parent_header'].get('msg_id') != msg_id:
|
|
# not from my request
|
|
continue
|
|
output_hook(msg)
|
|
|
|
# stop on idle
|
|
if msg['header']['msg_type'] == 'status' and \
|
|
msg['content']['execution_state'] == 'idle':
|
|
break
|
|
|
|
# output is done, get the reply
|
|
if timeout is not None:
|
|
timeout = max(0, deadline - monotonic())
|
|
return self._recv_reply(msg_id, timeout=timeout)
|