|
|
"""Base Widget class. Allows user to create widgets in the backend that render
|
|
|
in the IPython notebook frontend.
|
|
|
"""
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Copyright (c) 2013, the IPython Development Team.
|
|
|
#
|
|
|
# Distributed under the terms of the Modified BSD License.
|
|
|
#
|
|
|
# The full license is in the file COPYING.txt, distributed with this software.
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Imports
|
|
|
#-----------------------------------------------------------------------------
|
|
|
from copy import copy
|
|
|
from glob import glob
|
|
|
import uuid
|
|
|
import sys
|
|
|
import os
|
|
|
import inspect
|
|
|
import types
|
|
|
|
|
|
import IPython
|
|
|
from IPython.kernel.comm import Comm
|
|
|
from IPython.config import LoggingConfigurable
|
|
|
from IPython.utils.traitlets import Unicode, Dict, List, Instance, Bool
|
|
|
from IPython.display import Javascript, display
|
|
|
from IPython.utils.py3compat import string_types
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Classes
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
class Widget(LoggingConfigurable):
|
|
|
|
|
|
# Shared declarations (Class level)
|
|
|
widget_construction_callback = None
|
|
|
|
|
|
keys = ['view_name']
|
|
|
|
|
|
def on_widget_constructed(callback):
|
|
|
"""Class method, registers a callback to be called when a widget is
|
|
|
constructed. The callback must have the following signature:
|
|
|
callback(widget)"""
|
|
|
Widget.widget_construction_callback = callback
|
|
|
|
|
|
def _call_widget_constructed(widget):
|
|
|
"""Class method, called when a widget is constructed."""
|
|
|
if Widget.widget_construction_callback is not None and callable(Widget.widget_construction_callback):
|
|
|
Widget.widget_construction_callback(widget)
|
|
|
|
|
|
|
|
|
|
|
|
# Public declarations (Instance level)
|
|
|
target_name = Unicode('widget', help="""Name of the backbone model
|
|
|
registered in the frontend to create and sync this widget with.""")
|
|
|
view_name = Unicode(help="""Default view registered in the frontend
|
|
|
to use to represent the widget.""")
|
|
|
|
|
|
# Private/protected declarations
|
|
|
# todo: change this to a context manager
|
|
|
_property_lock = (None, None) # Last updated (key, value) from the front-end. Prevents echo.
|
|
|
_displayed = False
|
|
|
_comm = Instance('IPython.kernel.comm.Comm')
|
|
|
|
|
|
def __init__(self, **kwargs):
|
|
|
"""Public constructor
|
|
|
"""
|
|
|
self._display_callbacks = []
|
|
|
self._msg_callbacks = []
|
|
|
super(Widget, self).__init__(**kwargs)
|
|
|
|
|
|
self.on_trait_change(self._handle_property_changed, self.keys)
|
|
|
Widget._call_widget_constructed(self)
|
|
|
|
|
|
def __del__(self):
|
|
|
"""Object disposal"""
|
|
|
self.close()
|
|
|
|
|
|
|
|
|
def close(self):
|
|
|
"""Close method. Closes the widget which closes the underlying comm.
|
|
|
When the comm is closed, all of the widget views are automatically
|
|
|
removed from the frontend."""
|
|
|
self._close_communication()
|
|
|
|
|
|
@property
|
|
|
def comm(self):
|
|
|
if self._comm is None:
|
|
|
self._open_communication()
|
|
|
return self._comm
|
|
|
|
|
|
@property
|
|
|
def model_id(self):
|
|
|
return self.comm.comm_id
|
|
|
|
|
|
# Event handlers
|
|
|
def _handle_msg(self, msg):
|
|
|
"""Called when a msg is recieved from the frontend"""
|
|
|
data = msg['content']['data']
|
|
|
method = data['method']
|
|
|
|
|
|
# Handle backbone sync methods CREATE, PATCH, and UPDATE all in one.
|
|
|
if method == 'backbone' and 'sync_data' in data:
|
|
|
sync_data = data['sync_data']
|
|
|
self._handle_recieve_state(sync_data) # handles all methods
|
|
|
|
|
|
# Handle a custom msg from the front-end
|
|
|
elif method == 'custom':
|
|
|
if 'custom_content' in data:
|
|
|
self._handle_custom_msg(data['custom_content'])
|
|
|
|
|
|
def _handle_custom_msg(self, content):
|
|
|
"""Called when a custom msg is recieved."""
|
|
|
for handler in self._msg_callbacks:
|
|
|
if callable(handler):
|
|
|
argspec = inspect.getargspec(handler)
|
|
|
nargs = len(argspec[0])
|
|
|
|
|
|
# Bound methods have an additional 'self' argument
|
|
|
if isinstance(handler, types.MethodType):
|
|
|
nargs -= 1
|
|
|
|
|
|
# Call the callback
|
|
|
if nargs == 1:
|
|
|
handler(content)
|
|
|
elif nargs == 2:
|
|
|
handler(self, content)
|
|
|
else:
|
|
|
raise TypeError('Widget msg callback must ' \
|
|
|
'accept 1 or 2 arguments, not %d.' % nargs)
|
|
|
|
|
|
|
|
|
def _handle_recieve_state(self, sync_data):
|
|
|
"""Called when a state is recieved from the frontend."""
|
|
|
for name in self.keys:
|
|
|
if name in sync_data:
|
|
|
try:
|
|
|
self._property_lock = (name, sync_data[name])
|
|
|
setattr(self, name, sync_data[name])
|
|
|
finally:
|
|
|
self._property_lock = (None, None)
|
|
|
|
|
|
|
|
|
def _handle_property_changed(self, name, old, new):
|
|
|
"""Called when a property has been changed."""
|
|
|
# Make sure this isn't information that the front-end just sent us.
|
|
|
if self._property_lock[0] != name and self._property_lock[1] != new:
|
|
|
# Send new state to frontend
|
|
|
self.send_state(key=name)
|
|
|
|
|
|
def _handle_displayed(self, **kwargs):
|
|
|
"""Called when a view has been displayed for this widget instance
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
[view_name]: unicode (optional kwarg)
|
|
|
Name of the view that was displayed."""
|
|
|
for handler in self._display_callbacks:
|
|
|
if callable(handler):
|
|
|
argspec = inspect.getargspec(handler)
|
|
|
nargs = len(argspec[0])
|
|
|
|
|
|
# Bound methods have an additional 'self' argument
|
|
|
if isinstance(handler, types.MethodType):
|
|
|
nargs -= 1
|
|
|
|
|
|
# Call the callback
|
|
|
if nargs == 0:
|
|
|
handler()
|
|
|
elif nargs == 1:
|
|
|
handler(self)
|
|
|
elif nargs == 2:
|
|
|
handler(self, kwargs.get('view_name', None))
|
|
|
else:
|
|
|
handler(self, **kwargs)
|
|
|
|
|
|
# Public methods
|
|
|
def send_state(self, key=None):
|
|
|
"""Sends the widget state, or a piece of it, to the frontend.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
key : unicode (optional)
|
|
|
A single property's name to sync with the frontend.
|
|
|
"""
|
|
|
self._send({"method": "update",
|
|
|
"state": self.get_state()})
|
|
|
|
|
|
def get_state(self, key=None):
|
|
|
"""Gets the widget state, or a piece of it.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
key : unicode (optional)
|
|
|
A single property's name to get.
|
|
|
"""
|
|
|
state = {}
|
|
|
|
|
|
# If a key is provided, just send the state of that key.
|
|
|
if key is None:
|
|
|
keys = self.keys[:]
|
|
|
else:
|
|
|
keys = [key]
|
|
|
for k in keys:
|
|
|
value = getattr(self, k)
|
|
|
|
|
|
# a more elegant solution to encoding Widgets would be
|
|
|
# to tap into the JSON encoder and teach it how to deal
|
|
|
# with Widget objects, or maybe just teach the JSON
|
|
|
# encoder to look for a _repr_json property before giving
|
|
|
# up encoding
|
|
|
if isinstance(value, Widget):
|
|
|
value = value.model_id
|
|
|
elif isinstance(value, list) and len(value)>0 and isinstance(value[0], Widget):
|
|
|
# assume all elements of the list are widgets
|
|
|
value = [i.model_id for i in value]
|
|
|
state[k] = value
|
|
|
return state
|
|
|
|
|
|
|
|
|
def send(self, content):
|
|
|
"""Sends a custom msg to the widget model in the front-end.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
content : dict
|
|
|
Content of the message to send.
|
|
|
"""
|
|
|
self._send({"method": "custom",
|
|
|
"custom_content": content})
|
|
|
|
|
|
|
|
|
def on_msg(self, callback, remove=False):
|
|
|
"""Register a callback for when a custom msg is recieved from the front-end
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
callback: method handler
|
|
|
Can have a signature of:
|
|
|
- callback(content)
|
|
|
- callback(sender, content)
|
|
|
remove: bool
|
|
|
True if the callback should be unregistered."""
|
|
|
if remove and callback in self._msg_callbacks:
|
|
|
self._msg_callbacks.remove(callback)
|
|
|
elif not remove and not callback in self._msg_callbacks:
|
|
|
self._msg_callbacks.append(callback)
|
|
|
|
|
|
|
|
|
def on_displayed(self, callback, remove=False):
|
|
|
"""Register a callback to be called when the widget has been displayed
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
callback: method handler
|
|
|
Can have a signature of:
|
|
|
- callback()
|
|
|
- callback(sender)
|
|
|
- callback(sender, view_name)
|
|
|
- callback(sender, **kwargs)
|
|
|
kwargs from display call passed through without modification.
|
|
|
remove: bool
|
|
|
True if the callback should be unregistered."""
|
|
|
if remove and callback in self._display_callbacks:
|
|
|
self._display_callbacks.remove(callback)
|
|
|
elif not remove and not callback in self._display_callbacks:
|
|
|
self._display_callbacks.append(callback)
|
|
|
|
|
|
|
|
|
# Support methods
|
|
|
def _repr_widget_(self, **kwargs):
|
|
|
"""Function that is called when `IPython.display.display` is called on
|
|
|
the widget.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
view_name: unicode (optional)
|
|
|
View to display in the frontend. Overrides view_name."""
|
|
|
view_name = kwargs.get('view_name', self.view_name)
|
|
|
|
|
|
# Create a communication.
|
|
|
self._open_communication()
|
|
|
|
|
|
# Make sure model is syncronized
|
|
|
self.send_state()
|
|
|
|
|
|
# Show view.
|
|
|
self._send({"method": "display", "view_name": view_name})
|
|
|
self._displayed = True
|
|
|
self._handle_displayed(**kwargs)
|
|
|
|
|
|
|
|
|
def _open_communication(self):
|
|
|
"""Opens a communication with the front-end."""
|
|
|
# Create a comm.
|
|
|
if self._comm is None:
|
|
|
self._comm = Comm(target_name=self.target_name)
|
|
|
self._comm.on_msg(self._handle_msg)
|
|
|
self._comm.on_close(self._close_communication)
|
|
|
|
|
|
# first update
|
|
|
self.send_state()
|
|
|
|
|
|
|
|
|
def _close_communication(self):
|
|
|
"""Closes a communication with the front-end."""
|
|
|
if self._comm is not None:
|
|
|
try:
|
|
|
self._comm.close()
|
|
|
finally:
|
|
|
self._comm = None
|
|
|
|
|
|
|
|
|
def _send(self, msg):
|
|
|
"""Sends a message to the model in the front-end"""
|
|
|
if self._comm is not None:
|
|
|
self._comm.send(msg)
|
|
|
return True
|
|
|
else:
|
|
|
return False
|
|
|
|
|
|
|
|
|
class DOMWidget(Widget):
|
|
|
visible = Bool(True, help="Whether or not the widget is visible.")
|
|
|
|
|
|
# Private/protected declarations
|
|
|
_css = Dict() # Internal CSS property dict
|
|
|
|
|
|
keys = ['visible', '_css'] + Widget.keys
|
|
|
|
|
|
def get_css(self, key, selector=""):
|
|
|
"""Get a CSS property of the widget. Note, this function does not
|
|
|
actually request the CSS from the front-end; Only properties that have
|
|
|
been set with set_css can be read.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
key: unicode
|
|
|
CSS key
|
|
|
selector: unicode (optional)
|
|
|
JQuery selector used when the CSS key/value was set.
|
|
|
"""
|
|
|
if selector in self._css and key in self._css[selector]:
|
|
|
return self._css[selector][key]
|
|
|
else:
|
|
|
return None
|
|
|
|
|
|
|
|
|
def set_css(self, *args, **kwargs):
|
|
|
"""Set one or more CSS properties of the widget (shared among all of the
|
|
|
views). This function has two signatures:
|
|
|
- set_css(css_dict, [selector=''])
|
|
|
- set_css(key, value, [selector=''])
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
css_dict : dict
|
|
|
CSS key/value pairs to apply
|
|
|
key: unicode
|
|
|
CSS key
|
|
|
value
|
|
|
CSS value
|
|
|
selector: unicode (optional)
|
|
|
JQuery selector to use to apply the CSS key/value.
|
|
|
"""
|
|
|
selector = kwargs.get('selector', '')
|
|
|
|
|
|
# Signature 1: set_css(css_dict, [selector=''])
|
|
|
if len(args) == 1:
|
|
|
if isinstance(args[0], dict):
|
|
|
for (key, value) in args[0].items():
|
|
|
self.set_css(key, value, selector=selector)
|
|
|
else:
|
|
|
raise Exception('css_dict must be a dict.')
|
|
|
|
|
|
# Signature 2: set_css(key, value, [selector=''])
|
|
|
elif len(args) == 2 or len(args) == 3:
|
|
|
|
|
|
# Selector can be a positional arg if it's the 3rd value
|
|
|
if len(args) == 3:
|
|
|
selector = args[2]
|
|
|
if selector not in self._css:
|
|
|
self._css[selector] = {}
|
|
|
|
|
|
# Only update the property if it has changed.
|
|
|
key = args[0]
|
|
|
value = args[1]
|
|
|
if not (key in self._css[selector] and value in self._css[selector][key]):
|
|
|
self._css[selector][key] = value
|
|
|
self.send_state('_css') # Send new state to client.
|
|
|
else:
|
|
|
raise Exception('set_css only accepts 1-3 arguments')
|
|
|
|
|
|
|
|
|
def add_class(self, class_names, selector=""):
|
|
|
"""Add class[es] to a DOM element
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
class_names: unicode or list
|
|
|
Class name(s) to add to the DOM element(s).
|
|
|
selector: unicode (optional)
|
|
|
JQuery selector to select the DOM element(s) that the class(es) will
|
|
|
be added to.
|
|
|
"""
|
|
|
class_list = class_names
|
|
|
if isinstance(list, class_list):
|
|
|
class_list = ' '.join(class_list)
|
|
|
|
|
|
self.send({"msg_type": "add_class",
|
|
|
"class_list": class_list,
|
|
|
"selector": selector})
|
|
|
|
|
|
|
|
|
def remove_class(self, class_names, selector=""):
|
|
|
"""Remove class[es] from a DOM element
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
class_names: unicode or list
|
|
|
Class name(s) to remove from the DOM element(s).
|
|
|
selector: unicode (optional)
|
|
|
JQuery selector to select the DOM element(s) that the class(es) will
|
|
|
be removed from.
|
|
|
"""
|
|
|
class_list = class_names
|
|
|
if isinstance(list, class_list):
|
|
|
class_list = ' '.join(class_list)
|
|
|
|
|
|
self.send({"msg_type": "remove_class",
|
|
|
"class_list": class_list,
|
|
|
"selector": selector})
|
|
|
|
