##// END OF EJS Templates
The value of slider changes in frontend, and readout, but not in python obj.
The value of slider changes in frontend, and readout, but not in python obj.

File last commit:

r16586:095e73ab
r17275:43f23c53
Show More
interactiveshell.py
535 lines | 21.2 KiB | text/x-python | PythonLexer
# -*- coding: utf-8 -*-
"""terminal client to the IPython kernel"""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
from __future__ import print_function
import base64
import bdb
import signal
import os
import sys
import time
import subprocess
from getpass import getpass
from io import BytesIO
try:
from queue import Empty # Py 3
except ImportError:
from Queue import Empty # Py 2
from IPython.core import page
from IPython.core import release
from IPython.utils.warn import warn, error
from IPython.utils import io
from IPython.utils.py3compat import string_types, input
from IPython.utils.traitlets import List, Enum, Any, Instance, Unicode, Float
from IPython.utils.tempdir import NamedFileInTemporaryDirectory
from IPython.terminal.interactiveshell import TerminalInteractiveShell
from IPython.terminal.console.completer import ZMQCompleter
class ZMQTerminalInteractiveShell(TerminalInteractiveShell):
"""A subclass of TerminalInteractiveShell that uses the 0MQ kernel"""
_executing = False
_execution_state = Unicode('')
_pending_clearoutput = False
kernel_banner = Unicode('')
kernel_timeout = Float(60, config=True,
help="""Timeout for giving up on a kernel (in seconds).
On first connect and restart, the console tests whether the
kernel is running and responsive by sending kernel_info_requests.
This sets the timeout in seconds for how long the kernel can take
before being presumed dead.
"""
)
image_handler = Enum(('PIL', 'stream', 'tempfile', 'callable'),
config=True, help=
"""
Handler for image type output. This is useful, for example,
when connecting to the kernel in which pylab inline backend is
activated. There are four handlers defined. 'PIL': Use
Python Imaging Library to popup image; 'stream': Use an
external program to show the image. Image will be fed into
the STDIN of the program. You will need to configure
`stream_image_handler`; 'tempfile': Use an external program to
show the image. Image will be saved in a temporally file and
the program is called with the temporally file. You will need
to configure `tempfile_image_handler`; 'callable': You can set
any Python callable which is called with the image data. You
will need to configure `callable_image_handler`.
"""
)
stream_image_handler = List(config=True, help=
"""
Command to invoke an image viewer program when you are using
'stream' image handler. This option is a list of string where
the first element is the command itself and reminders are the
options for the command. Raw image data is given as STDIN to
the program.
"""
)
tempfile_image_handler = List(config=True, help=
"""
Command to invoke an image viewer program when you are using
'tempfile' image handler. This option is a list of string
where the first element is the command itself and reminders
are the options for the command. You can use {file} and
{format} in the string to represent the location of the
generated image file and image format.
"""
)
callable_image_handler = Any(config=True, help=
"""
Callable object called via 'callable' image handler with one
argument, `data`, which is `msg["content"]["data"]` where
`msg` is the message from iopub channel. For exmaple, you can
find base64 encoded PNG data as `data['image/png']`.
"""
)
mime_preference = List(
default_value=['image/png', 'image/jpeg', 'image/svg+xml'],
config=True, allow_none=False, help=
"""
Preferred object representation MIME type in order. First
matched MIME type will be used.
"""
)
manager = Instance('IPython.kernel.KernelManager')
client = Instance('IPython.kernel.KernelClient')
def _client_changed(self, name, old, new):
self.session_id = new.session.session
session_id = Unicode()
def init_completer(self):
"""Initialize the completion machinery.
This creates completion machinery that can be used by client code,
either interactively in-process (typically triggered by the readline
library), programmatically (such as in test suites) or out-of-process
(typically over the network by remote frontends).
"""
from IPython.core.completerlib import (module_completer,
magic_run_completer, cd_completer)
self.Completer = ZMQCompleter(self, self.client, config=self.config)
self.set_hook('complete_command', module_completer, str_key = 'import')
self.set_hook('complete_command', module_completer, str_key = 'from')
self.set_hook('complete_command', magic_run_completer, str_key = '%run')
self.set_hook('complete_command', cd_completer, str_key = '%cd')
# Only configure readline if we truly are using readline. IPython can
# do tab-completion over the network, in GUIs, etc, where readline
# itself may be absent
if self.has_readline:
self.set_readline_completer()
def ask_exit(self):
super(ZMQTerminalInteractiveShell, self).ask_exit()
if self.exit_now and self.manager:
self.client.shutdown()
def run_cell(self, cell, store_history=True):
"""Run a complete IPython cell.
Parameters
----------
cell : str
The code (including IPython code such as %magic functions) to run.
store_history : bool
If True, the raw and translated cell will be stored in IPython's
history. For user code calling back into IPython's machinery, this
should be set to False.
"""
if (not cell) or cell.isspace():
# pressing enter flushes any pending display
self.handle_iopub()
return
if cell.strip() == 'exit':
# explicitly handle 'exit' command
return self.ask_exit()
# flush stale replies, which could have been ignored, due to missed heartbeats
while self.client.shell_channel.msg_ready():
self.client.shell_channel.get_msg()
# shell_channel.execute takes 'hidden', which is the inverse of store_hist
msg_id = self.client.shell_channel.execute(cell, not store_history)
# first thing is wait for any side effects (output, stdin, etc.)
self._executing = True
self._execution_state = "busy"
while self._execution_state != 'idle' and self.client.is_alive():
try:
self.handle_input_request(msg_id, timeout=0.05)
except Empty:
# display intermediate print statements, etc.
self.handle_iopub(msg_id)
# after all of that is done, wait for the execute reply
while self.client.is_alive():
try:
self.handle_execute_reply(msg_id, timeout=0.05)
except Empty:
pass
else:
break
self._executing = False
#-----------------
# message handlers
#-----------------
def handle_execute_reply(self, msg_id, timeout=None):
msg = self.client.shell_channel.get_msg(block=False, timeout=timeout)
if msg["parent_header"].get("msg_id", None) == msg_id:
self.handle_iopub(msg_id)
content = msg["content"]
status = content['status']
if status == 'aborted':
self.write('Aborted\n')
return
elif status == 'ok':
# handle payloads
for item in content["payload"]:
source = item['source']
if source == 'page':
page.page(item['data']['text/plain'])
elif source == 'set_next_input':
self.set_next_input(item['text'])
elif status == 'error':
for frame in content["traceback"]:
print(frame, file=io.stderr)
self.execution_count = int(content["execution_count"] + 1)
def handle_iopub(self, msg_id=''):
"""Process messages on the IOPub channel
This method consumes and processes messages on the IOPub channel,
such as stdout, stderr, execute_result and status.
It only displays output that is caused by this session.
"""
while self.client.iopub_channel.msg_ready():
sub_msg = self.client.iopub_channel.get_msg()
msg_type = sub_msg['header']['msg_type']
parent = sub_msg["parent_header"]
if parent.get("session", self.session_id) == self.session_id:
if msg_type == 'status':
self._execution_state = sub_msg["content"]["execution_state"]
elif msg_type == 'stream':
if sub_msg["content"]["name"] == "stdout":
if self._pending_clearoutput:
print("\r", file=io.stdout, end="")
self._pending_clearoutput = False
print(sub_msg["content"]["data"], file=io.stdout, end="")
io.stdout.flush()
elif sub_msg["content"]["name"] == "stderr" :
if self._pending_clearoutput:
print("\r", file=io.stderr, end="")
self._pending_clearoutput = False
print(sub_msg["content"]["data"], file=io.stderr, end="")
io.stderr.flush()
elif msg_type == 'execute_result':
if self._pending_clearoutput:
print("\r", file=io.stdout, end="")
self._pending_clearoutput = False
self.execution_count = int(sub_msg["content"]["execution_count"])
format_dict = sub_msg["content"]["data"]
self.handle_rich_data(format_dict)
# taken from DisplayHook.__call__:
hook = self.displayhook
hook.start_displayhook()
hook.write_output_prompt()
hook.write_format_data(format_dict)
hook.log_output(format_dict)
hook.finish_displayhook()
elif msg_type == 'display_data':
data = sub_msg["content"]["data"]
handled = self.handle_rich_data(data)
if not handled:
# if it was an image, we handled it by now
if 'text/plain' in data:
print(data['text/plain'])
elif msg_type == 'clear_output':
if sub_msg["content"]["wait"]:
self._pending_clearoutput = True
else:
print("\r", file=io.stdout, end="")
_imagemime = {
'image/png': 'png',
'image/jpeg': 'jpeg',
'image/svg+xml': 'svg',
}
def handle_rich_data(self, data):
for mime in self.mime_preference:
if mime in data and mime in self._imagemime:
self.handle_image(data, mime)
return True
def handle_image(self, data, mime):
handler = getattr(
self, 'handle_image_{0}'.format(self.image_handler), None)
if handler:
handler(data, mime)
def handle_image_PIL(self, data, mime):
if mime not in ('image/png', 'image/jpeg'):
return
import PIL.Image
raw = base64.decodestring(data[mime].encode('ascii'))
img = PIL.Image.open(BytesIO(raw))
img.show()
def handle_image_stream(self, data, mime):
raw = base64.decodestring(data[mime].encode('ascii'))
imageformat = self._imagemime[mime]
fmt = dict(format=imageformat)
args = [s.format(**fmt) for s in self.stream_image_handler]
with open(os.devnull, 'w') as devnull:
proc = subprocess.Popen(
args, stdin=subprocess.PIPE,
stdout=devnull, stderr=devnull)
proc.communicate(raw)
def handle_image_tempfile(self, data, mime):
raw = base64.decodestring(data[mime].encode('ascii'))
imageformat = self._imagemime[mime]
filename = 'tmp.{0}'.format(imageformat)
with NamedFileInTemporaryDirectory(filename) as f, \
open(os.devnull, 'w') as devnull:
f.write(raw)
f.flush()
fmt = dict(file=f.name, format=imageformat)
args = [s.format(**fmt) for s in self.tempfile_image_handler]
subprocess.call(args, stdout=devnull, stderr=devnull)
def handle_image_callable(self, data, mime):
self.callable_image_handler(data)
def handle_input_request(self, msg_id, timeout=0.1):
""" Method to capture raw_input
"""
req = self.client.stdin_channel.get_msg(timeout=timeout)
# in case any iopub came while we were waiting:
self.handle_iopub(msg_id)
if msg_id == req["parent_header"].get("msg_id"):
# wrap SIGINT handler
real_handler = signal.getsignal(signal.SIGINT)
def double_int(sig,frame):
# call real handler (forwards sigint to kernel),
# then raise local interrupt, stopping local raw_input
real_handler(sig,frame)
raise KeyboardInterrupt
signal.signal(signal.SIGINT, double_int)
content = req['content']
read = getpass if content.get('password', False) else input
try:
raw_data = read(content["prompt"])
except EOFError:
# turn EOFError into EOF character
raw_data = '\x04'
except KeyboardInterrupt:
sys.stdout.write('\n')
return
finally:
# restore SIGINT handler
signal.signal(signal.SIGINT, real_handler)
# only send stdin reply if there *was not* another request
# or execution finished while we were reading.
if not (self.client.stdin_channel.msg_ready() or self.client.shell_channel.msg_ready()):
self.client.stdin_channel.input(raw_data)
def mainloop(self, display_banner=False):
while True:
try:
self.interact(display_banner=display_banner)
#self.interact_with_readline()
# XXX for testing of a readline-decoupled repl loop, call
# interact_with_readline above
break
except KeyboardInterrupt:
# this should not be necessary, but KeyboardInterrupt
# handling seems rather unpredictable...
self.write("\nKeyboardInterrupt in interact()\n")
def _banner1_default(self):
return "IPython Console {version}\n".format(version=release.version)
def compute_banner(self):
super(ZMQTerminalInteractiveShell, self).compute_banner()
if self.client and not self.kernel_banner:
msg_id = self.client.kernel_info()
while True:
try:
reply = self.client.get_shell_msg(timeout=1)
except Empty:
break
else:
if reply['parent_header'].get('msg_id') == msg_id:
self.kernel_banner = reply['content'].get('banner', '')
break
self.banner += self.kernel_banner
def wait_for_kernel(self, timeout=None):
"""method to wait for a kernel to be ready"""
tic = time.time()
self.client.hb_channel.unpause()
while True:
msg_id = self.client.kernel_info()
reply = None
while True:
try:
reply = self.client.get_shell_msg(timeout=1)
except Empty:
break
else:
if reply['parent_header'].get('msg_id') == msg_id:
return True
if timeout is not None \
and (time.time() - tic) > timeout \
and not self.client.hb_channel.is_beating():
# heart failed
return False
return True
def interact(self, display_banner=None):
"""Closely emulate the interactive Python console."""
# batch run -> do not interact
if self.exit_now:
return
if display_banner is None:
display_banner = self.display_banner
if isinstance(display_banner, string_types):
self.show_banner(display_banner)
elif display_banner:
self.show_banner()
more = False
# run a non-empty no-op, so that we don't get a prompt until
# we know the kernel is ready. This keeps the connection
# message above the first prompt.
if not self.wait_for_kernel(self.kernel_timeout):
error("Kernel did not respond\n")
return
if self.has_readline:
self.readline_startup_hook(self.pre_readline)
hlen_b4_cell = self.readline.get_current_history_length()
else:
hlen_b4_cell = 0
# exit_now is set by a call to %Exit or %Quit, through the
# ask_exit callback.
while not self.exit_now:
if not self.client.is_alive():
# kernel died, prompt for action or exit
action = "restart" if self.manager else "wait for restart"
ans = self.ask_yes_no("kernel died, %s ([y]/n)?" % action, default='y')
if ans:
if self.manager:
self.manager.restart_kernel(True)
self.wait_for_kernel(self.kernel_timeout)
else:
self.exit_now = True
continue
try:
# protect prompt block from KeyboardInterrupt
# when sitting on ctrl-C
self.hooks.pre_prompt_hook()
if more:
try:
prompt = self.prompt_manager.render('in2')
except Exception:
self.showtraceback()
if self.autoindent:
self.rl_do_indent = True
else:
try:
prompt = self.separate_in + self.prompt_manager.render('in')
except Exception:
self.showtraceback()
line = self.raw_input(prompt)
if self.exit_now:
# quick exit on sys.std[in|out] close
break
if self.autoindent:
self.rl_do_indent = False
except KeyboardInterrupt:
#double-guard against keyboardinterrupts during kbdint handling
try:
self.write('\nKeyboardInterrupt\n')
source_raw = self.input_splitter.raw_reset()
hlen_b4_cell = self._replace_rlhist_multiline(source_raw, hlen_b4_cell)
more = False
except KeyboardInterrupt:
pass
except EOFError:
if self.autoindent:
self.rl_do_indent = False
if self.has_readline:
self.readline_startup_hook(None)
self.write('\n')
self.exit()
except bdb.BdbQuit:
warn('The Python debugger has exited with a BdbQuit exception.\n'
'Because of how pdb handles the stack, it is impossible\n'
'for IPython to properly format this particular exception.\n'
'IPython will resume normal operation.')
except:
# exceptions here are VERY RARE, but they can be triggered
# asynchronously by signal handlers, for example.
self.showtraceback()
else:
try:
self.input_splitter.push(line)
more = self.input_splitter.push_accepts_more()
except SyntaxError:
# Run the code directly - run_cell takes care of displaying
# the exception.
more = False
if (self.SyntaxTB.last_syntax_error and
self.autoedit_syntax):
self.edit_syntax_error()
if not more:
source_raw = self.input_splitter.raw_reset()
hlen_b4_cell = self._replace_rlhist_multiline(source_raw, hlen_b4_cell)
self.run_cell(source_raw)
# Turn off the exit flag, so the mainloop can be restarted if desired
self.exit_now = False