Backport PR #8203: autosave & reload on kernelspec switch

when a custom kernel.js was defined, in which case reload is needed to ensure clean js state.

closes  #7783

IPython/html/static/notebook/js/kernelselector.js

@@ -1,325 +1,335 b''
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 define([
     'jquery',
     'base/js/namespace',
     'base/js/dialog',
     'base/js/utils',
 ], function($, IPython, dialog, utils) {
     "use strict";
     
     var KernelSelector = function(selector, notebook) {
         var that = this;
         this.selector = selector;
         this.notebook = notebook;
         this.notebook.set_kernelselector(this);
         this.events = notebook.events;
         this.current_selection = null;
         this.kernelspecs = {};
         if (this.selector !== undefined) {
             this.element = $(selector);
             this.request_kernelspecs();
         }
         this.bind_events();
         // Make the object globally available for user convenience & inspection
         IPython.kernelselector = this;
         this._finish_load = null;
         this._loaded = false;
         this.loaded = new Promise(function(resolve) {
             that._finish_load = resolve;
         });
         
         Object.seal(this);
     };
     
     KernelSelector.prototype.request_kernelspecs = function() {
         var url = utils.url_join_encode(this.notebook.base_url, 'api/kernelspecs');
         utils.promising_ajax(url).then($.proxy(this._got_kernelspecs, this));
     };
     
     var _sorted_names = function(kernelspecs) {
         // sort kernel names
         return Object.keys(kernelspecs).sort(function (a, b) {
             // sort by display_name
             var da = kernelspecs[a].spec.display_name;
             var db = kernelspecs[b].spec.display_name;
             if (da === db) {
                 return 0;
             } else if (da > db) {
                 return 1;
             } else {
                 return -1;
             }
         });
     };
     
     KernelSelector.prototype._got_kernelspecs = function(data) {
         var that = this;
         this.kernelspecs = data.kernelspecs;
         var change_kernel_submenu = $("#menu-change-kernel-submenu");
         var new_notebook_submenu = $("#menu-new-notebook-submenu");
         var keys = _sorted_names(data.kernelspecs);
         
         keys.map(function (key) {
             // Create the Kernel > Change kernel submenu
             var ks = data.kernelspecs[key];
             change_kernel_submenu.append(
                 $("<li>").attr("id", "kernel-submenu-"+ks.name).append(
                     $('<a>')
                         .attr('href', '#')
                         .click( function () {
                             that.set_kernel(ks.name);
                         })
                         .text(ks.spec.display_name)
                 )
             );
             // Create the File > New Notebook submenu
             new_notebook_submenu.append(
                 $("<li>").attr("id", "new-notebook-submenu-"+ks.name).append(
                     $('<a>')
                         .attr('href', '#')
                         .click( function () {
                             that.new_notebook(ks.name);
                         })
                         .text(ks.spec.display_name)
                 )
             );
 
         });
         // trigger loaded promise
         this._loaded = true;
         this._finish_load();
     };
     
     KernelSelector.prototype._spec_changed = function (event, ks) {
         /** event handler for spec_changed */
+        var that = this;
         
         // update selection
         this.current_selection = ks.name;
         
         // put the current kernel at the top of File > New Notebook
         var cur_kernel_entry = $("#new-notebook-submenu-" + ks.name);
         var parent = cur_kernel_entry.parent();
         // do something only if there is more than one kernel
         if (parent.children().length > 1) {
             // first, sort back the submenu
             parent.append(
                 parent.children("li[class!='divider']").sort(
                     function (a,b) {
                         var da = $("a",a).text();
                         var db = $("a",b).text();
                         if (da === db) {
                             return 0;
                         } else if (da > db) {
                             return 1;
                         } else {
                             return -1;
                         }}));
             // then, if there is no divider yet, add one
             if (!parent.children("li[class='divider']").length) {
                 parent.prepend($("<li>").attr("class","divider"));
             } 
             // finally, put the current kernel at the top
             parent.prepend(cur_kernel_entry);
         }
         
         // load logo
         var logo_img = this.element.find("img.current_kernel_logo");
         $("#kernel_indicator").find('.kernel_indicator_name').text(ks.spec.display_name);
         if (ks.resources['logo-64x64']) {
             logo_img.attr("src", ks.resources['logo-64x64']);
             logo_img.show();
         } else {
             logo_img.hide();
         }
         
         // load kernel css
         var css_url = ks.resources['kernel.css'];
         if (css_url) {
             $('#kernel-css').attr('href', css_url);
         } else {
             $('#kernel-css').attr('href', '');
         }
         
         // load kernel js
         if (ks.resources['kernel.js']) {
             require([ks.resources['kernel.js']],
                 function (kernel_mod) {
                     if (kernel_mod && kernel_mod.onload) {
                         kernel_mod.onload();
                     } else {
                         console.warn("Kernel " + ks.name + " has a kernel.js file that does not contain "+
                                      "any asynchronous module definition. This is undefined behavior "+
                                      "and not recommended.");
                     }
                 }, function (err) {
                     console.warn("Failed to load kernel.js from ", ks.resources['kernel.js'], err);
                 }
             );
+            this.events.on('spec_changed.Kernel', function (evt, new_ks) {
+                if (ks.name != new_ks.name) {
+                    console.warn("kernelspec %s had custom kernel.js. Forcing page reload for %s.",
+                        ks.name, new_ks.name);
+                    that.notebook.save_notebook().then(function () {
+                        window.location.reload();
+                    });
+                }
+            });
         }
     };
 
     KernelSelector.prototype.set_kernel = function (selected) {
         /** set the kernel by name, ensuring kernelspecs have been loaded, first 
         
         kernel can be just a kernel name, or a notebook kernelspec metadata
         (name, language, display_name).
         */
         var that = this;
         if (typeof selected === 'string') {
             selected = {
                 name: selected
             };
         }
         if (this._loaded) {
             this._set_kernel(selected);
         } else {
             return this.loaded.then(function () {
                 that._set_kernel(selected);
             });
         }
     };
 
     KernelSelector.prototype._set_kernel = function (selected) {
         /** Actually set the kernel (kernelspecs have been loaded) */
         if (selected.name === this.current_selection) {
             // only trigger event if value changed
             return;
         }
         var kernelspecs = this.kernelspecs;
         var ks = kernelspecs[selected.name];
         if (ks === undefined) {
             var available = _sorted_names(kernelspecs);
             var matches = [];
             if (selected.language && selected.language.length > 0) {
                 available.map(function (name) {
                     if (kernelspecs[name].spec.language.toLowerCase() === selected.language.toLowerCase()) {
                         matches.push(name);
                     }
                 });
             }
             if (matches.length === 1) {
                 ks = kernelspecs[matches[0]];
                 console.log("No exact match found for " + selected.name +
                     ", using only kernel that matches language=" + selected.language, ks);
                 this.events.trigger("spec_match_found.Kernel", {
                     selected: selected,
                     found: ks,
                 });
             }
             // if still undefined, trigger failure event
             if (ks === undefined) {
                 this.events.trigger("spec_not_found.Kernel", {
                     selected: selected,
                     matches: matches,
                     available: available,
                 });
                 return;
             }
         }
         if (this.notebook._session_starting &&
             this.notebook.session.kernel.name !== ks.name) {
             console.error("Cannot change kernel while waiting for pending session start.");
             return;
         }
         this.current_selection = ks.name;
         this.events.trigger('spec_changed.Kernel', ks);
     };
     
     KernelSelector.prototype._spec_not_found = function (event, data) {
         var that = this;
         var select = $("<select>").addClass('form-control');
         console.warn("Kernelspec not found:", data);
         var names;
         if (data.matches.length > 1) {
             names = data.matches;
         } else {
             names = data.available;
         }
         names.map(function (name) {
             var ks = that.kernelspecs[name];
             select.append(
                 $('<option/>').attr('value', ks.name).text(ks.spec.display_name || ks.name)
             );
         });
         
         var body = $("<form>").addClass("form-inline").append(
             $("<span>").text(
                 "I couldn't find a kernel matching " + (data.selected.display_name || data.selected.name) + "." +
                 " Please select a kernel:"
             )
         ).append(select);
         
         dialog.modal({
             title : 'Kernel not found',
             body : body,
             buttons : {
                 'Continue without kernel' : {
                     class : 'btn-danger',
                     click : function () {
                         that.events.trigger('no_kernel.Kernel');
                     }
                 },
                 OK : {
                     class : 'btn-primary',
                     click : function () {
                         that.set_kernel(select.val());
                     }
                 }
             }
         });
     };
 
     KernelSelector.prototype.new_notebook = function (kernel_name) {
         
         var w = window.open('', IPython._target);
         // Create a new notebook in the same path as the current
         // notebook's path.
         var that = this;
         var parent = utils.url_path_split(that.notebook.notebook_path)[0];
         that.notebook.contents.new_untitled(parent, {type: "notebook"}).then(
             function (data) {
                 var url = utils.url_join_encode(
                     that.notebook.base_url, 'notebooks', data.path
                 );
                 url += "?kernel_name=" + kernel_name;
                 w.location = url;
             },
             function(error) {
                 w.close();
                 dialog.modal({
                     title : 'Creating Notebook Failed',
                     body : "The error was: " + error.message,
                     buttons : {'OK' : {'class' : 'btn-primary'}}
                 });
             }
         );
     };
 
     KernelSelector.prototype.lock_switch = function() {
         // should set a flag and display warning+reload if user want to
         // re-change kernel. As UI discussion never finish
         // making that a separate PR.
         console.warn('switching kernel is not guaranteed to work !');
     };
 
     KernelSelector.prototype.bind_events = function() {
         var that = this;
         this.events.on('spec_changed.Kernel', $.proxy(this._spec_changed, this));
         this.events.on('spec_not_found.Kernel', $.proxy(this._spec_not_found, this));
         this.events.on('kernel_created.Session', function (event, data) {
             that.set_kernel(data.kernel.name);
         });
         
         var logo_img = this.element.find("img.current_kernel_logo");
         logo_img.on("load", function() {
             logo_img.show();
         });
         logo_img.on("error", function() {
             logo_img.hide();
         });
     };
 
     return {'KernelSelector': KernelSelector};
 });