fr/fr_env/lib/python3.8/site-packages/matplotlib/backends/backend_nbagg.py

264 lines
8.4 KiB
Python

"""Interactive figures in the IPython notebook"""
# Note: There is a notebook in
# lib/matplotlib/backends/web_backend/nbagg_uat.ipynb to help verify
# that changes made maintain expected behaviour.
from base64 import b64encode
import io
import json
import pathlib
import uuid
from IPython.display import display, Javascript, HTML
try:
# Jupyter/IPython 4.x or later
from ipykernel.comm import Comm
except ImportError:
# Jupyter/IPython 3.x or earlier
from IPython.kernel.comm import Comm
from matplotlib import cbook, is_interactive
from matplotlib._pylab_helpers import Gcf
from matplotlib.backend_bases import _Backend, NavigationToolbar2
from matplotlib.backends.backend_webagg_core import (
FigureCanvasWebAggCore, FigureManagerWebAgg, NavigationToolbar2WebAgg,
TimerTornado)
def connection_info():
"""
Return a string showing the figure and connection status for the backend.
This is intended as a diagnostic tool, and not for general use.
"""
result = [
'{fig} - {socket}'.format(
fig=(manager.canvas.figure.get_label()
or "Figure {}".format(manager.num)),
socket=manager.web_sockets)
for manager in Gcf.get_all_fig_managers()
]
if not is_interactive():
result.append(f'Figures pending show: {len(Gcf.figs)}')
return '\n'.join(result)
# Note: Version 3.2 and 4.x icons
# http://fontawesome.io/3.2.1/icons/
# http://fontawesome.io/
# the `fa fa-xxx` part targets font-awesome 4, (IPython 3.x)
# the icon-xxx targets font awesome 3.21 (IPython 2.x)
_FONT_AWESOME_CLASSES = {
'home': 'fa fa-home icon-home',
'back': 'fa fa-arrow-left icon-arrow-left',
'forward': 'fa fa-arrow-right icon-arrow-right',
'zoom_to_rect': 'fa fa-square-o icon-check-empty',
'move': 'fa fa-arrows icon-move',
'download': 'fa fa-floppy-o icon-save',
None: None
}
class NavigationIPy(NavigationToolbar2WebAgg):
# Use the standard toolbar items + download button
toolitems = [(text, tooltip_text,
_FONT_AWESOME_CLASSES[image_file], name_of_method)
for text, tooltip_text, image_file, name_of_method
in (NavigationToolbar2.toolitems +
(('Download', 'Download plot', 'download', 'download'),))
if image_file in _FONT_AWESOME_CLASSES]
class FigureManagerNbAgg(FigureManagerWebAgg):
ToolbarCls = NavigationIPy
def __init__(self, canvas, num):
self._shown = False
FigureManagerWebAgg.__init__(self, canvas, num)
def display_js(self):
# XXX How to do this just once? It has to deal with multiple
# browser instances using the same kernel (require.js - but the
# file isn't static?).
display(Javascript(FigureManagerNbAgg.get_javascript()))
def show(self):
if not self._shown:
self.display_js()
self._create_comm()
else:
self.canvas.draw_idle()
self._shown = True
def reshow(self):
"""
A special method to re-show the figure in the notebook.
"""
self._shown = False
self.show()
@property
def connected(self):
return bool(self.web_sockets)
@classmethod
def get_javascript(cls, stream=None):
if stream is None:
output = io.StringIO()
else:
output = stream
super().get_javascript(stream=output)
output.write((pathlib.Path(__file__).parent
/ "web_backend/js/nbagg_mpl.js")
.read_text(encoding="utf-8"))
if stream is None:
return output.getvalue()
def _create_comm(self):
comm = CommSocket(self)
self.add_web_socket(comm)
return comm
def destroy(self):
self._send_event('close')
# need to copy comms as callbacks will modify this list
for comm in list(self.web_sockets):
comm.on_close()
self.clearup_closed()
def clearup_closed(self):
"""Clear up any closed Comms."""
self.web_sockets = {socket for socket in self.web_sockets
if socket.is_open()}
if len(self.web_sockets) == 0:
self.canvas.close_event()
def remove_comm(self, comm_id):
self.web_sockets = {socket for socket in self.web_sockets
if socket.comm.comm_id != comm_id}
class FigureCanvasNbAgg(FigureCanvasWebAggCore):
_timer_cls = TimerTornado
class CommSocket:
"""
Manages the Comm connection between IPython and the browser (client).
Comms are 2 way, with the CommSocket being able to publish a message
via the send_json method, and handle a message with on_message. On the
JS side figure.send_message and figure.ws.onmessage do the sending and
receiving respectively.
"""
def __init__(self, manager):
self.supports_binary = None
self.manager = manager
self.uuid = str(uuid.uuid4())
# Publish an output area with a unique ID. The javascript can then
# hook into this area.
display(HTML("<div id=%r></div>" % self.uuid))
try:
self.comm = Comm('matplotlib', data={'id': self.uuid})
except AttributeError as err:
raise RuntimeError('Unable to create an IPython notebook Comm '
'instance. Are you in the IPython '
'notebook?') from err
self.comm.on_msg(self.on_message)
manager = self.manager
self._ext_close = False
def _on_close(close_message):
self._ext_close = True
manager.remove_comm(close_message['content']['comm_id'])
manager.clearup_closed()
self.comm.on_close(_on_close)
def is_open(self):
return not (self._ext_close or self.comm._closed)
def on_close(self):
# When the socket is closed, deregister the websocket with
# the FigureManager.
if self.is_open():
try:
self.comm.close()
except KeyError:
# apparently already cleaned it up?
pass
def send_json(self, content):
self.comm.send({'data': json.dumps(content)})
def send_binary(self, blob):
# The comm is ascii, so we always send the image in base64
# encoded data URL form.
data = b64encode(blob).decode('ascii')
data_uri = "data:image/png;base64,{0}".format(data)
self.comm.send({'data': data_uri})
def on_message(self, message):
# The 'supports_binary' message is relevant to the
# websocket itself. The other messages get passed along
# to matplotlib as-is.
# Every message has a "type" and a "figure_id".
message = json.loads(message['content']['data'])
if message['type'] == 'closing':
self.on_close()
self.manager.clearup_closed()
elif message['type'] == 'supports_binary':
self.supports_binary = message['value']
else:
self.manager.handle_json(message)
@_Backend.export
class _BackendNbAgg(_Backend):
FigureCanvas = FigureCanvasNbAgg
FigureManager = FigureManagerNbAgg
@staticmethod
def new_figure_manager_given_figure(num, figure):
canvas = FigureCanvasNbAgg(figure)
manager = FigureManagerNbAgg(canvas, num)
if is_interactive():
manager.show()
figure.canvas.draw_idle()
canvas.mpl_connect('close_event', lambda event: Gcf.destroy(manager))
return manager
@staticmethod
def trigger_manager_draw(manager):
manager.show()
@staticmethod
def show(block=None):
## TODO: something to do when keyword block==False ?
from matplotlib._pylab_helpers import Gcf
managers = Gcf.get_all_fig_managers()
if not managers:
return
interactive = is_interactive()
for manager in managers:
manager.show()
# plt.figure adds an event which makes the figure in focus the
# active one. Disable this behaviour, as it results in
# figures being put as the active figure after they have been
# shown, even in non-interactive mode.
if hasattr(manager, '_cidgcf'):
manager.canvas.mpl_disconnect(manager._cidgcf)
if not interactive:
Gcf.figs.pop(manager.num, None)