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widget.js
808 lines | 31.6 KiB | application/javascript | JavascriptLexer
// Copyright (c) IPython Development Team.
// Distributed under the terms of the Modified BSD License.
define(["widgets/js/manager",
"underscore",
"backbone",
"jquery",
"base/js/utils",
"base/js/namespace",
], function(widgetmanager, _, Backbone, $, utils, IPython){
"use strict";
var unpack_models = function unpack_models(value, model) {
/**
* Replace model ids with models recursively.
*/
var unpacked;
if ($.isArray(value)) {
unpacked = [];
_.each(value, function(sub_value, key) {
unpacked.push(unpack_models(sub_value, model));
});
return Promise.all(unpacked);
} else if (value instanceof Object) {
unpacked = {};
_.each(value, function(sub_value, key) {
unpacked[key] = unpack_models(sub_value, model);
});
return utils.resolve_promises_dict(unpacked);
} else if (typeof value === 'string' && value.slice(0,10) === "IPY_MODEL_") {
// get_model returns a promise already
return model.widget_manager.get_model(value.slice(10, value.length));
} else {
return Promise.resolve(value);
}
};
var WidgetModel = Backbone.Model.extend({
constructor: function (widget_manager, model_id, comm) {
/**
* Constructor
*
* Creates a WidgetModel instance.
*
* Parameters
* ----------
* widget_manager : WidgetManager instance
* model_id : string
* An ID unique to this model.
* comm : Comm instance (optional)
*/
this.widget_manager = widget_manager;
this.state_change = Promise.resolve();
this._buffered_state_diff = {};
this.pending_msgs = 0;
this.msg_buffer = null;
this.state_lock = null;
this.id = model_id;
this.views = {};
this._resolve_received_state = {};
if (comm !== undefined) {
// Remember comm associated with the model.
this.comm = comm;
comm.model = this;
// Hook comm messages up to model.
comm.on_close($.proxy(this._handle_comm_closed, this));
comm.on_msg($.proxy(this._handle_comm_msg, this));
// Assume the comm is alive.
this.set_comm_live(true);
} else {
this.set_comm_live(false);
}
// Listen for the events that lead to the websocket being terminated.
var that = this;
var died = function() {
that.set_comm_live(false);
};
widget_manager.notebook.events.on('kernel_disconnected.Kernel', died);
widget_manager.notebook.events.on('kernel_killed.Kernel', died);
widget_manager.notebook.events.on('kernel_restarting.Kernel', died);
widget_manager.notebook.events.on('kernel_dead.Kernel', died);
return Backbone.Model.apply(this);
},
send: function (content, callbacks, buffers) {
/**
* Send a custom msg over the comm.
*/
if (this.comm !== undefined) {
var data = {method: 'custom', content: content};
this.comm.send(data, callbacks, {}, buffers);
this.pending_msgs++;
}
},
request_state: function(callbacks) {
/**
* Request a state push from the back-end.
*/
if (!this.comm) {
console.error("Could not request_state because comm doesn't exist!");
return;
}
var msg_id = this.comm.send({method: 'request_state'}, callbacks || this.widget_manager.callbacks());
// Promise that is resolved when a state is received
// from the back-end.
var that = this;
var received_state = new Promise(function(resolve) {
that._resolve_received_state[msg_id] = resolve;
});
return received_state;
},
set_comm_live: function(live) {
/**
* Change the comm_live state of the model.
*/
if (this.comm_live === undefined || this.comm_live != live) {
this.comm_live = live;
this.trigger(live ? 'comm:live' : 'comm:dead', {model: this});
}
},
close: function(comm_closed) {
/**
* Close model
*/
if (this.comm && !comm_closed) {
this.comm.close();
}
this.stopListening();
this.trigger('destroy', this);
delete this.comm.model; // Delete ref so GC will collect widget model.
delete this.comm;
delete this.model_id; // Delete id from model so widget manager cleans up.
_.each(this.views, function(v, id, views) {
v.then(function(view) {
view.remove();
delete views[id];
});
});
},
_handle_comm_closed: function (msg) {
/**
* Handle when a widget is closed.
*/
this.trigger('comm:close');
this.close(true);
},
_handle_comm_msg: function (msg) {
/**
* Handle incoming comm msg.
*/
var method = msg.content.data.method;
var that = this;
switch (method) {
case 'update':
this.state_change = this.state_change
.then(function() {
var state = msg.content.data.state || {};
var buffer_keys = msg.content.data.buffers || [];
var buffers = msg.buffers || [];
for (var i=0; i<buffer_keys.length; i++) {
state[buffer_keys[i]] = buffers[i];
}
// deserialize fields that have custom deserializers
var serializers = that.constructor.serializers;
if (serializers) {
for (var k in state) {
if (serializers[k] && serializers[k].deserialize) {
state[k] = (serializers[k].deserialize)(state[k], that);
}
}
}
return utils.resolve_promises_dict(state);
}).then(function(state) {
return that.set_state(state);
}).catch(utils.reject("Couldn't process update msg for model id '" + String(that.id) + "'", true))
.then(function() {
var parent_id = msg.parent_header.msg_id;
if (that._resolve_received_state[parent_id] !== undefined) {
that._resolve_received_state[parent_id].call();
delete that._resolve_received_state[parent_id];
}
}).catch(utils.reject("Couldn't resolve state request promise", true));
break;
case 'custom':
this.trigger('msg:custom', msg.content.data.content, msg.buffers);
break;
case 'display':
this.state_change = this.state_change.then(function() {
that.widget_manager.display_view(msg, that);
}).catch(utils.reject('Could not process display view msg', true));
break;
}
},
set_state: function (state) {
var that = this;
// Handle when a widget is updated via the python side.
return new Promise(function(resolve, reject) {
that.state_lock = state;
try {
WidgetModel.__super__.set.call(that, state);
} finally {
that.state_lock = null;
}
resolve();
}).catch(utils.reject("Couldn't set model state", true));
},
get_state: function() {
// Get the serializable state of the model.
// Equivalent to Backbone.Model.toJSON()
return _.clone(this.attributes);
},
_handle_status: function (msg, callbacks) {
/**
* Handle status msgs.
*
* execution_state : ('busy', 'idle', 'starting')
*/
if (this.comm !== undefined) {
if (msg.content.execution_state ==='idle') {
// Send buffer if this message caused another message to be
// throttled.
if (this.msg_buffer !== null &&
(this.get('msg_throttle') || 3) === this.pending_msgs) {
var data = {method: 'backbone', sync_method: 'update', sync_data: this.msg_buffer};
this.comm.send(data, callbacks);
this.msg_buffer = null;
} else {
--this.pending_msgs;
}
}
}
},
callbacks: function(view) {
/**
* Create msg callbacks for a comm msg.
*/
var callbacks = this.widget_manager.callbacks(view);
if (callbacks.iopub === undefined) {
callbacks.iopub = {};
}
var that = this;
callbacks.iopub.status = function (msg) {
that._handle_status(msg, callbacks);
};
return callbacks;
},
set: function(key, val, options) {
/**
* Set a value.
*/
var return_value = WidgetModel.__super__.set.apply(this, arguments);
// Backbone only remembers the diff of the most recent set()
// operation. Calling set multiple times in a row results in a
// loss of diff information. Here we keep our own running diff.
this._buffered_state_diff = $.extend(this._buffered_state_diff, this.changedAttributes() || {});
return return_value;
},
sync: function (method, model, options) {
/**
* Handle sync to the back-end. Called when a model.save() is called.
*
* Make sure a comm exists.
* Parameters
* ----------
* method : create, update, patch, delete, read
* create/update always send the full attribute set
* patch - only send attributes listed in options.attrs, and if we are queuing
* up messages, combine with previous messages that have not been sent yet
* model : the model we are syncing
* will normally be the same as `this`
* options : dict
* the `attrs` key, if it exists, gives an {attr: value} dict that should be synced,
* otherwise, sync all attributes
*
*/
var error = options.error || function() {
console.error('Backbone sync error:', arguments);
};
if (this.comm === undefined) {
error();
return false;
}
var attrs = (method === 'patch') ? options.attrs : model.get_state(options);
// the state_lock lists attributes that are currently be changed right now from a kernel message
// we don't want to send these non-changes back to the kernel, so we delete them out of attrs
// (but we only delete them if the value hasn't changed from the value stored in the state_lock
if (this.state_lock !== null) {
var keys = Object.keys(this.state_lock);
for (var i=0; i<keys.length; i++) {
var key = keys[i];
if (attrs[key] === this.state_lock[key]) {
delete attrs[key];
}
}
}
if (_.size(attrs) > 0) {
// If this message was sent via backbone itself, it will not
// have any callbacks. It's important that we create callbacks
// so we can listen for status messages, etc...
var callbacks = options.callbacks || this.callbacks();
// Check throttle.
if (this.pending_msgs >= (this.get('msg_throttle') || 3)) {
// The throttle has been exceeded, buffer the current msg so
// it can be sent once the kernel has finished processing
// some of the existing messages.
// Combine updates if it is a 'patch' sync, otherwise replace updates
switch (method) {
case 'patch':
this.msg_buffer = $.extend(this.msg_buffer || {}, attrs);
break;
case 'update':
case 'create':
this.msg_buffer = attrs;
break;
default:
error();
return false;
}
this.msg_buffer_callbacks = callbacks;
} else {
// We haven't exceeded the throttle, send the message like
// normal.
this.send_sync_message(attrs, callbacks);
this.pending_msgs++;
}
}
// Since the comm is a one-way communication, assume the message
// arrived. Don't call success since we don't have a model back from the server
// this means we miss out on the 'sync' event.
this._buffered_state_diff = {};
},
send_sync_message: function(attrs, callbacks) {
// prepare and send a comm message syncing attrs
var that = this;
// first, build a state dictionary with key=the attribute and the value
// being the value or the promise of the serialized value
var serializers = this.constructor.serializers;
if (serializers) {
for (var k in attrs) {
if (serializers[k] && serializers[k].serialize) {
attrs[k] = (serializers[k].serialize)(attrs[k], this);
}
}
}
utils.resolve_promises_dict(attrs).then(function(state) {
// get binary values, then send
var keys = Object.keys(state);
var buffers = [];
var buffer_keys = [];
for (var i=0; i<keys.length; i++) {
var key = keys[i];
var value = state[key];
if (value) {
if (value.buffer instanceof ArrayBuffer
|| value instanceof ArrayBuffer) {
buffers.push(value);
buffer_keys.push(key);
delete state[key];
}
}
}
that.comm.send({method: 'backbone', sync_data: state, buffer_keys: buffer_keys}, callbacks, {}, buffers);
}).catch(function(error) {
that.pending_msgs--;
return (utils.reject("Couldn't send widget sync message", true))(error);
});
},
save_changes: function(callbacks) {
/**
* Push this model's state to the back-end
*
* This invokes a Backbone.Sync.
*/
this.save(this._buffered_state_diff, {patch: true, callbacks: callbacks});
},
on_some_change: function(keys, callback, context) {
/**
* on_some_change(["key1", "key2"], foo, context) differs from
* on("change:key1 change:key2", foo, context).
* If the widget attributes key1 and key2 are both modified,
* the second form will result in foo being called twice
* while the first will call foo only once.
*/
this.on('change', function() {
if (keys.some(this.hasChanged, this)) {
callback.apply(context);
}
}, this);
},
toJSON: function(options) {
/**
* Serialize the model. See the types.js deserialization function
* and the kernel-side serializer/deserializer
*/
return "IPY_MODEL_"+this.id;
}
});
widgetmanager.WidgetManager.register_widget_model('WidgetModel', WidgetModel);
var WidgetView = Backbone.View.extend({
initialize: function(parameters) {
/**
* Public constructor.
*/
this.model.on('change',this.update,this);
// Bubble the comm live events.
this.model.on('comm:live', function() {
this.trigger('comm:live', this);
}, this);
this.model.on('comm:dead', function() {
this.trigger('comm:dead', this);
}, this);
this.options = parameters.options;
this.on('displayed', function() {
this.is_displayed = true;
}, this);
},
update: function(){
/**
* Triggered on model change.
*
* Update view to be consistent with this.model
*/
},
create_child_view: function(child_model, options) {
/**
* Create and promise that resolves to a child view of a given model
*/
var that = this;
options = $.extend({ parent: this }, options || {});
return this.model.widget_manager.create_view(child_model, options).catch(utils.reject("Couldn't create child view", true));
},
callbacks: function(){
/**
* Create msg callbacks for a comm msg.
*/
return this.model.callbacks(this);
},
render: function(){
/**
* Render the view.
*
* By default, this is only called the first time the view is created
*/
},
send: function (content, buffers) {
/**
* Send a custom msg associated with this view.
*/
this.model.send(content, this.callbacks(), buffers);
},
touch: function () {
this.model.save_changes(this.callbacks());
},
after_displayed: function (callback, context) {
/**
* Calls the callback right away is the view is already displayed
* otherwise, register the callback to the 'displayed' event.
*/
if (this.is_displayed) {
callback.apply(context);
} else {
this.on('displayed', callback, context);
}
},
remove: function () {
// Raise a remove event when the view is removed.
WidgetView.__super__.remove.apply(this, arguments);
this.trigger('remove');
}
});
var DOMWidgetView = WidgetView.extend({
initialize: function (parameters) {
/**
* Public constructor
*/
DOMWidgetView.__super__.initialize.apply(this, [parameters]);
this.model.on('change:visible', this.update_visible, this);
this.model.on('change:_css', this.update_css, this);
this.model.on('change:_dom_classes', function(model, new_classes) {
var old_classes = model.previous('_dom_classes');
this.update_classes(old_classes, new_classes);
}, this);
this.model.on('change:color', function (model, value) {
this.update_attr('color', value); }, this);
this.model.on('change:background_color', function (model, value) {
this.update_attr('background', value); }, this);
this.model.on('change:width', function (model, value) {
this.update_attr('width', value); }, this);
this.model.on('change:height', function (model, value) {
this.update_attr('height', value); }, this);
this.model.on('change:border_color', function (model, value) {
this.update_attr('border-color', value); }, this);
this.model.on('change:border_width', function (model, value) {
this.update_attr('border-width', value); }, this);
this.model.on('change:border_style', function (model, value) {
this.update_attr('border-style', value); }, this);
this.model.on('change:font_style', function (model, value) {
this.update_attr('font-style', value); }, this);
this.model.on('change:font_weight', function (model, value) {
this.update_attr('font-weight', value); }, this);
this.model.on('change:font_size', function (model, value) {
this.update_attr('font-size', this._default_px(value)); }, this);
this.model.on('change:font_family', function (model, value) {
this.update_attr('font-family', value); }, this);
this.model.on('change:padding', function (model, value) {
this.update_attr('padding', value); }, this);
this.model.on('change:margin', function (model, value) {
this.update_attr('margin', this._default_px(value)); }, this);
this.model.on('change:border_radius', function (model, value) {
this.update_attr('border-radius', this._default_px(value)); }, this);
this.after_displayed(function() {
this.update_visible(this.model, this.model.get("visible"));
this.update_classes([], this.model.get('_dom_classes'));
this.update_attr('color', this.model.get('color'));
this.update_attr('background', this.model.get('background_color'));
this.update_attr('width', this.model.get('width'));
this.update_attr('height', this.model.get('height'));
this.update_attr('border-color', this.model.get('border_color'));
this.update_attr('border-width', this.model.get('border_width'));
this.update_attr('border-style', this.model.get('border_style'));
this.update_attr('font-style', this.model.get('font_style'));
this.update_attr('font-weight', this.model.get('font_weight'));
this.update_attr('font-size', this._default_px(this.model.get('font_size')));
this.update_attr('font-family', this.model.get('font_family'));
this.update_attr('padding', this.model.get('padding'));
this.update_attr('margin', this._default_px(this.model.get('margin')));
this.update_attr('border-radius', this._default_px(this.model.get('border_radius')));
this.update_css(this.model, this.model.get("_css"));
}, this);
},
_default_px: function(value) {
/**
* Makes browser interpret a numerical string as a pixel value.
*/
if (value && /^\d+\.?(\d+)?$/.test(value.trim())) {
return value.trim() + 'px';
}
return value;
},
update_attr: function(name, value) {
/**
* Set a css attr of the widget view.
*/
this.$el.css(name, value);
},
update_visible: function(model, value) {
/**
* Update visibility
*/
switch(value) {
case null: // python None
this.$el.show().css('visibility', 'hidden'); break;
case false:
this.$el.hide(); break;
case true:
this.$el.show().css('visibility', ''); break;
}
},
update_css: function (model, css) {
/**
* Update the css styling of this view.
*/
if (css === undefined) {return;}
for (var i = 0; i < css.length; i++) {
// Apply the css traits to all elements that match the selector.
var selector = css[i][0];
var elements = this._get_selector_element(selector);
if (elements.length > 0) {
var trait_key = css[i][1];
var trait_value = css[i][2];
elements.css(trait_key ,trait_value);
}
}
},
update_classes: function (old_classes, new_classes, $el) {
/**
* Update the DOM classes applied to an element, default to this.$el.
*/
if ($el===undefined) {
$el = this.$el;
}
_.difference(old_classes, new_classes).map(function(c) {$el.removeClass(c);})
_.difference(new_classes, old_classes).map(function(c) {$el.addClass(c);})
},
update_mapped_classes: function(class_map, trait_name, previous_trait_value, $el) {
/**
* Update the DOM classes applied to the widget based on a single
* trait's value.
*
* Given a trait value classes map, this function automatically
* handles applying the appropriate classes to the widget element
* and removing classes that are no longer valid.
*
* Parameters
* ----------
* class_map: dictionary
* Dictionary of trait values to class lists.
* Example:
* {
* success: ['alert', 'alert-success'],
* info: ['alert', 'alert-info'],
* warning: ['alert', 'alert-warning'],
* danger: ['alert', 'alert-danger']
* };
* trait_name: string
* Name of the trait to check the value of.
* previous_trait_value: optional string, default ''
* Last trait value
* $el: optional jQuery element handle, defaults to this.$el
* Element that the classes are applied to.
*/
var key = previous_trait_value;
if (key === undefined) {
key = this.model.previous(trait_name);
}
var old_classes = class_map[key] ? class_map[key] : [];
key = this.model.get(trait_name);
var new_classes = class_map[key] ? class_map[key] : [];
this.update_classes(old_classes, new_classes, $el || this.$el);
},
_get_selector_element: function (selector) {
/**
* Get the elements via the css selector.
*/
var elements;
if (!selector) {
elements = this.$el;
} else {
elements = this.$el.find(selector).addBack(selector);
}
return elements;
},
typeset: function(element, text){
utils.typeset.apply(null, arguments);
},
});
var ViewList = function(create_view, remove_view, context) {
/**
* - create_view and remove_view are default functions called when adding or removing views
* - create_view takes a model and returns a view or a promise for a view for that model
* - remove_view takes a view and destroys it (including calling `view.remove()`)
* - each time the update() function is called with a new list, the create and remove
* callbacks will be called in an order so that if you append the views created in the
* create callback and remove the views in the remove callback, you will duplicate
* the order of the list.
* - the remove callback defaults to just removing the view (e.g., pass in null for the second parameter)
* - the context defaults to the created ViewList. If you pass another context, the create and remove
* will be called in that context.
*/
this.initialize.apply(this, arguments);
};
_.extend(ViewList.prototype, {
initialize: function(create_view, remove_view, context) {
this._handler_context = context || this;
this._models = [];
this.views = []; // list of promises for views
this._create_view = create_view;
this._remove_view = remove_view || function(view) {view.remove();};
},
update: function(new_models, create_view, remove_view, context) {
/**
* the create_view, remove_view, and context arguments override the defaults
* specified when the list is created.
* after this function, the .views attribute is a list of promises for views
* if you want to perform some action on the list of views, do something like
* `Promise.all(myviewlist.views).then(function(views) {...});`
*/
var remove = remove_view || this._remove_view;
var create = create_view || this._create_view;
context = context || this._handler_context;
var i = 0;
// first, skip past the beginning of the lists if they are identical
for (; i < new_models.length; i++) {
if (i >= this._models.length || new_models[i] !== this._models[i]) {
break;
}
}
var first_removed = i;
// Remove the non-matching items from the old list.
var removed = this.views.splice(first_removed, this.views.length-first_removed);
for (var j = 0; j < removed.length; j++) {
removed[j].then(function(view) {
remove.call(context, view)
});
}
// Add the rest of the new list items.
for (; i < new_models.length; i++) {
this.views.push(Promise.resolve(create.call(context, new_models[i])));
}
// make a copy of the input array
this._models = new_models.slice();
},
remove: function() {
/**
* removes every view in the list; convenience function for `.update([])`
* that should be faster
* returns a promise that resolves after this removal is done
*/
var that = this;
return Promise.all(this.views).then(function(views) {
for (var i = 0; i < that.views.length; i++) {
that._remove_view.call(that._handler_context, views[i]);
}
that.views = [];
that._models = [];
});
},
});
var widget = {
'unpack_models': unpack_models,
'WidgetModel': WidgetModel,
'WidgetView': WidgetView,
'DOMWidgetView': DOMWidgetView,
'ViewList': ViewList,
};
// For backwards compatability.
$.extend(IPython, widget);
return widget;
});