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.
327 lines
11 KiB
Python
327 lines
11 KiB
Python
"""Displays Agg images in the browser, with interactivity."""
|
|
|
|
# The WebAgg backend is divided into two modules:
|
|
#
|
|
# - `backend_webagg_core.py` contains code necessary to embed a WebAgg
|
|
# plot inside of a web application, and communicate in an abstract
|
|
# way over a web socket.
|
|
#
|
|
# - `backend_webagg.py` contains a concrete implementation of a basic
|
|
# application, implemented with tornado.
|
|
|
|
from contextlib import contextmanager
|
|
import errno
|
|
from io import BytesIO
|
|
import json
|
|
import mimetypes
|
|
from pathlib import Path
|
|
import random
|
|
import sys
|
|
import signal
|
|
import threading
|
|
|
|
try:
|
|
import tornado.web
|
|
import tornado.ioloop
|
|
import tornado.websocket
|
|
except ImportError as err:
|
|
raise RuntimeError("The WebAgg backend requires Tornado.") from err
|
|
|
|
import matplotlib as mpl
|
|
from matplotlib.backend_bases import _Backend
|
|
from matplotlib._pylab_helpers import Gcf
|
|
from . import backend_webagg_core as core
|
|
from .backend_webagg_core import ( # noqa: F401 # pylint: disable=W0611
|
|
TimerAsyncio, TimerTornado)
|
|
|
|
|
|
webagg_server_thread = threading.Thread(
|
|
target=lambda: tornado.ioloop.IOLoop.instance().start())
|
|
|
|
|
|
class FigureManagerWebAgg(core.FigureManagerWebAgg):
|
|
_toolbar2_class = core.NavigationToolbar2WebAgg
|
|
|
|
@classmethod
|
|
def pyplot_show(cls, *, block=None):
|
|
WebAggApplication.initialize()
|
|
|
|
url = "http://{address}:{port}{prefix}".format(
|
|
address=WebAggApplication.address,
|
|
port=WebAggApplication.port,
|
|
prefix=WebAggApplication.url_prefix)
|
|
|
|
if mpl.rcParams['webagg.open_in_browser']:
|
|
import webbrowser
|
|
if not webbrowser.open(url):
|
|
print(f"To view figure, visit {url}")
|
|
else:
|
|
print(f"To view figure, visit {url}")
|
|
|
|
WebAggApplication.start()
|
|
|
|
|
|
class FigureCanvasWebAgg(core.FigureCanvasWebAggCore):
|
|
manager_class = FigureManagerWebAgg
|
|
|
|
|
|
class WebAggApplication(tornado.web.Application):
|
|
initialized = False
|
|
started = False
|
|
|
|
class FavIcon(tornado.web.RequestHandler):
|
|
def get(self):
|
|
self.set_header('Content-Type', 'image/png')
|
|
self.write(Path(mpl.get_data_path(),
|
|
'images/matplotlib.png').read_bytes())
|
|
|
|
class SingleFigurePage(tornado.web.RequestHandler):
|
|
def __init__(self, application, request, *, url_prefix='', **kwargs):
|
|
self.url_prefix = url_prefix
|
|
super().__init__(application, request, **kwargs)
|
|
|
|
def get(self, fignum):
|
|
fignum = int(fignum)
|
|
manager = Gcf.get_fig_manager(fignum)
|
|
|
|
ws_uri = f'ws://{self.request.host}{self.url_prefix}/'
|
|
self.render(
|
|
"single_figure.html",
|
|
prefix=self.url_prefix,
|
|
ws_uri=ws_uri,
|
|
fig_id=fignum,
|
|
toolitems=core.NavigationToolbar2WebAgg.toolitems,
|
|
canvas=manager.canvas)
|
|
|
|
class AllFiguresPage(tornado.web.RequestHandler):
|
|
def __init__(self, application, request, *, url_prefix='', **kwargs):
|
|
self.url_prefix = url_prefix
|
|
super().__init__(application, request, **kwargs)
|
|
|
|
def get(self):
|
|
ws_uri = f'ws://{self.request.host}{self.url_prefix}/'
|
|
self.render(
|
|
"all_figures.html",
|
|
prefix=self.url_prefix,
|
|
ws_uri=ws_uri,
|
|
figures=sorted(Gcf.figs.items()),
|
|
toolitems=core.NavigationToolbar2WebAgg.toolitems)
|
|
|
|
class MplJs(tornado.web.RequestHandler):
|
|
def get(self):
|
|
self.set_header('Content-Type', 'application/javascript')
|
|
|
|
js_content = core.FigureManagerWebAgg.get_javascript()
|
|
|
|
self.write(js_content)
|
|
|
|
class Download(tornado.web.RequestHandler):
|
|
def get(self, fignum, fmt):
|
|
fignum = int(fignum)
|
|
manager = Gcf.get_fig_manager(fignum)
|
|
self.set_header(
|
|
'Content-Type', mimetypes.types_map.get(fmt, 'binary'))
|
|
buff = BytesIO()
|
|
manager.canvas.figure.savefig(buff, format=fmt)
|
|
self.write(buff.getvalue())
|
|
|
|
class WebSocket(tornado.websocket.WebSocketHandler):
|
|
supports_binary = True
|
|
|
|
def open(self, fignum):
|
|
self.fignum = int(fignum)
|
|
self.manager = Gcf.get_fig_manager(self.fignum)
|
|
self.manager.add_web_socket(self)
|
|
if hasattr(self, 'set_nodelay'):
|
|
self.set_nodelay(True)
|
|
|
|
def on_close(self):
|
|
self.manager.remove_web_socket(self)
|
|
|
|
def on_message(self, message):
|
|
message = json.loads(message)
|
|
# The 'supports_binary' message is on a client-by-client
|
|
# basis. The others affect the (shared) canvas as a
|
|
# whole.
|
|
if message['type'] == 'supports_binary':
|
|
self.supports_binary = message['value']
|
|
else:
|
|
manager = Gcf.get_fig_manager(self.fignum)
|
|
# It is possible for a figure to be closed,
|
|
# but a stale figure UI is still sending messages
|
|
# from the browser.
|
|
if manager is not None:
|
|
manager.handle_json(message)
|
|
|
|
def send_json(self, content):
|
|
self.write_message(json.dumps(content))
|
|
|
|
def send_binary(self, blob):
|
|
if self.supports_binary:
|
|
self.write_message(blob, binary=True)
|
|
else:
|
|
data_uri = "data:image/png;base64,{}".format(
|
|
blob.encode('base64').replace('\n', ''))
|
|
self.write_message(data_uri)
|
|
|
|
def __init__(self, url_prefix=''):
|
|
if url_prefix:
|
|
assert url_prefix[0] == '/' and url_prefix[-1] != '/', \
|
|
'url_prefix must start with a "/" and not end with one.'
|
|
|
|
super().__init__(
|
|
[
|
|
# Static files for the CSS and JS
|
|
(url_prefix + r'/_static/(.*)',
|
|
tornado.web.StaticFileHandler,
|
|
{'path': core.FigureManagerWebAgg.get_static_file_path()}),
|
|
|
|
# Static images for the toolbar
|
|
(url_prefix + r'/_images/(.*)',
|
|
tornado.web.StaticFileHandler,
|
|
{'path': Path(mpl.get_data_path(), 'images')}),
|
|
|
|
# A Matplotlib favicon
|
|
(url_prefix + r'/favicon.ico', self.FavIcon),
|
|
|
|
# The page that contains all of the pieces
|
|
(url_prefix + r'/([0-9]+)', self.SingleFigurePage,
|
|
{'url_prefix': url_prefix}),
|
|
|
|
# The page that contains all of the figures
|
|
(url_prefix + r'/?', self.AllFiguresPage,
|
|
{'url_prefix': url_prefix}),
|
|
|
|
(url_prefix + r'/js/mpl.js', self.MplJs),
|
|
|
|
# Sends images and events to the browser, and receives
|
|
# events from the browser
|
|
(url_prefix + r'/([0-9]+)/ws', self.WebSocket),
|
|
|
|
# Handles the downloading (i.e., saving) of static images
|
|
(url_prefix + r'/([0-9]+)/download.([a-z0-9.]+)',
|
|
self.Download),
|
|
],
|
|
template_path=core.FigureManagerWebAgg.get_static_file_path())
|
|
|
|
@classmethod
|
|
def initialize(cls, url_prefix='', port=None, address=None):
|
|
if cls.initialized:
|
|
return
|
|
|
|
# Create the class instance
|
|
app = cls(url_prefix=url_prefix)
|
|
|
|
cls.url_prefix = url_prefix
|
|
|
|
# This port selection algorithm is borrowed, more or less
|
|
# verbatim, from IPython.
|
|
def random_ports(port, n):
|
|
"""
|
|
Generate a list of n random ports near the given port.
|
|
|
|
The first 5 ports will be sequential, and the remaining n-5 will be
|
|
randomly selected in the range [port-2*n, port+2*n].
|
|
"""
|
|
for i in range(min(5, n)):
|
|
yield port + i
|
|
for i in range(n - 5):
|
|
yield port + random.randint(-2 * n, 2 * n)
|
|
|
|
if address is None:
|
|
cls.address = mpl.rcParams['webagg.address']
|
|
else:
|
|
cls.address = address
|
|
cls.port = mpl.rcParams['webagg.port']
|
|
for port in random_ports(cls.port,
|
|
mpl.rcParams['webagg.port_retries']):
|
|
try:
|
|
app.listen(port, cls.address)
|
|
except OSError as e:
|
|
if e.errno != errno.EADDRINUSE:
|
|
raise
|
|
else:
|
|
cls.port = port
|
|
break
|
|
else:
|
|
raise SystemExit(
|
|
"The webagg server could not be started because an available "
|
|
"port could not be found")
|
|
|
|
cls.initialized = True
|
|
|
|
@classmethod
|
|
def start(cls):
|
|
import asyncio
|
|
try:
|
|
asyncio.get_running_loop()
|
|
except RuntimeError:
|
|
pass
|
|
else:
|
|
cls.started = True
|
|
|
|
if cls.started:
|
|
return
|
|
|
|
"""
|
|
IOLoop.running() was removed as of Tornado 2.4; see for example
|
|
https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
|
|
Thus there is no correct way to check if the loop has already been
|
|
launched. We may end up with two concurrently running loops in that
|
|
unlucky case with all the expected consequences.
|
|
"""
|
|
ioloop = tornado.ioloop.IOLoop.instance()
|
|
|
|
def shutdown():
|
|
ioloop.stop()
|
|
print("Server is stopped")
|
|
sys.stdout.flush()
|
|
cls.started = False
|
|
|
|
@contextmanager
|
|
def catch_sigint():
|
|
old_handler = signal.signal(
|
|
signal.SIGINT,
|
|
lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
|
|
try:
|
|
yield
|
|
finally:
|
|
signal.signal(signal.SIGINT, old_handler)
|
|
|
|
# Set the flag to True *before* blocking on ioloop.start()
|
|
cls.started = True
|
|
|
|
print("Press Ctrl+C to stop WebAgg server")
|
|
sys.stdout.flush()
|
|
with catch_sigint():
|
|
ioloop.start()
|
|
|
|
|
|
def ipython_inline_display(figure):
|
|
import tornado.template
|
|
|
|
WebAggApplication.initialize()
|
|
import asyncio
|
|
try:
|
|
asyncio.get_running_loop()
|
|
except RuntimeError:
|
|
if not webagg_server_thread.is_alive():
|
|
webagg_server_thread.start()
|
|
|
|
fignum = figure.number
|
|
tpl = Path(core.FigureManagerWebAgg.get_static_file_path(),
|
|
"ipython_inline_figure.html").read_text()
|
|
t = tornado.template.Template(tpl)
|
|
return t.generate(
|
|
prefix=WebAggApplication.url_prefix,
|
|
fig_id=fignum,
|
|
toolitems=core.NavigationToolbar2WebAgg.toolitems,
|
|
canvas=figure.canvas,
|
|
port=WebAggApplication.port).decode('utf-8')
|
|
|
|
|
|
@_Backend.export
|
|
class _BackendWebAgg(_Backend):
|
|
FigureCanvas = FigureCanvasWebAgg
|
|
FigureManager = FigureManagerWebAgg
|