Update Voila shell

packages/voila/src/plugins/widget.ts

@@ -149,5 +149,10 @@ export const renderOutputsPlugin: JupyterFrontEndPlugin<void> = {
         Widget.attach(output, container);
       }
     });
+    const node = document.getElementById('rendered_cells');
+    if (node) {
+      const cells = new Widget({ node });
+      app.shell.add(cells, 'main');
+    }
   }
 };

packages/voila/src/shell.ts

@@ -6,12 +6,13 @@
  *                                                                          *
  * The full license is in the file LICENSE, distributed with this software. *
  ****************************************************************************/
-
 import { JupyterFrontEnd } from '@jupyterlab/application';
-
 import { DocumentRegistry } from '@jupyterlab/docregistry';
-
-import { Widget } from '@lumino/widgets';
+import { ArrayExt } from '@lumino/algorithm';
+import { IMessageHandler, Message, MessageLoop } from '@lumino/messaging';
+import { Debouncer } from '@lumino/polling';
+import { Signal } from '@lumino/signaling';
+import { BoxLayout, BoxPanel, Panel, Widget } from '@lumino/widgets';
 
 export type IShell = VoilaShell;
 
@@ -22,16 +23,67 @@ export namespace IShell {
   /**
    * The areas of the application shell where widgets can reside.
    */
-  export type Area = 'main';
+  export type Area =
+    | 'main'
+    | 'header'
+    | 'top'
+    | 'menu'
+    | 'left'
+    | 'right'
+    | 'bottom'
+    | 'down';
 }
 
+/**
+ * The class name added to AppShell instances.
+ */
+const APPLICATION_SHELL_CLASS = 'jp-LabShell';
+
+/**
+ * The default rank of items added to a sidebar.
+ */
+const DEFAULT_RANK = 900;
+
 /**
  * The application shell.
  */
 export class VoilaShell extends Widget implements JupyterFrontEnd.IShell {
   constructor() {
     super();
     this.id = 'main';
+    const rootLayout = new BoxLayout();
+    rootLayout.alignment = 'start';
+    rootLayout.spacing = 0;
+    this.addClass(APPLICATION_SHELL_CLASS);
+
+    const topHandler = (this._topHandler = new Private.PanelHandler());
+    topHandler.panel.id = 'voila-top-panel';
+    topHandler.panel.node.setAttribute('role', 'banner');
+    BoxLayout.setStretch(topHandler.panel, 0);
+    topHandler.panel.hide();
+    rootLayout.addWidget(topHandler.panel);
+
+    const hboxPanel = (this._mainPanel = new BoxPanel());
+    hboxPanel.id = 'jp-main-content-panel';
+    hboxPanel.direction = 'top-to-bottom';
+    BoxLayout.setStretch(hboxPanel, 1);
+    rootLayout.addWidget(hboxPanel);
+
+    const bottomPanel = (this._bottomPanel = new Panel());
+    bottomPanel.node.setAttribute('role', 'contentinfo');
+    bottomPanel.id = 'voila-bottom-panel';
+    BoxLayout.setStretch(bottomPanel, 0);
+    rootLayout.addWidget(bottomPanel);
+    bottomPanel.hide();
+
+    this.layout = rootLayout;
+  }
+
+  /**
+   * The current widget in the shell's main area.
+   */
+  get currentWidget(): Widget | null {
+    return this._mainPanel.widgets[0];
   }
 
   activateById(id: string): void {
@@ -52,18 +104,183 @@ export class VoilaShell extends Widget implements JupyterFrontEnd.IShell {
     area?: IShell.Area,
     options?: DocumentRegistry.IOpenOptions
   ): void {
-    // no-op for now
-    // TODO: support adding widgets to areas?
+    switch (area) {
+      case 'top':
+        this._addToTopArea(widget, options);
+        break;
+      case 'bottom':
+        this._addToBottomArea(widget, options);
+        break;
+      case 'main':
+        this._mainPanel.addWidget(widget);
+        break;
+      default:
+        console.warn(`Area ${area} is not implemented yet!`);
+        break;
+    }
+  }
+
+  widgets(area: IShell.Area): IterableIterator<Widget> {
+    switch (area) {
+      case 'top':
+        return this._topHandler.panel.children();
+      case 'bottom':
+        return this._bottomPanel.children();
+      case 'main':
+        this._mainPanel.children();
+        break;
+      default:
+        return [][Symbol.iterator]();
+    }
+    return [][Symbol.iterator]();
   }
 
   /**
-   * The current widget in the shell's main area.
+   * Add a widget to the top content area.
+   *
+   * #### Notes
+   * Widgets must have a unique `id` property, which will be used as the DOM id.
    */
-  get currentWidget(): Widget | null {
-    return null;
+  private _addToTopArea(
+    widget: Widget,
+    options?: DocumentRegistry.IOpenOptions
+  ): void {
+    if (!widget.id) {
+      console.error('Widgets added to app shell must have unique id property.');
+      return;
+    }
+    options = options || {};
+    const rank = options.rank ?? DEFAULT_RANK;
+    this._topHandler.addWidget(widget, rank);
+    this._onLayoutModified();
+    if (this._topHandler.panel.isHidden) {
+      this._topHandler.panel.show();
+    }
   }
 
-  widgets(area: IShell.Area): IterableIterator<Widget> {
-    return [][Symbol.iterator]();
+  /**
+   * Add a widget to the bottom content area.
+   *
+   * #### Notes
+   * Widgets must have a unique `id` property, which will be used as the DOM id.
+   */
+  private _addToBottomArea(
+    widget: Widget,
+    options?: DocumentRegistry.IOpenOptions
+  ): void {
+    if (!widget.id) {
+      console.error('Widgets added to app shell must have unique id property.');
+      return;
+    }
+    this._bottomPanel.addWidget(widget);
+    this._onLayoutModified();
+
+    if (this._bottomPanel.isHidden) {
+      this._bottomPanel.show();
+    }
+  }
+
+  /**
+   * Handle a change to the layout.
+   */
+  private _onLayoutModified(): void {
+    void this._layoutDebouncer.invoke();
+  }
+
+  private _topHandler: Private.PanelHandler;
+  private _mainPanel: BoxPanel;
+  private _bottomPanel: Panel;
+  private _layoutDebouncer = new Debouncer(() => {
+    this._layoutModified.emit(undefined);
+  }, 0);
+  private _layoutModified = new Signal<this, void>(this);
+}
+
+namespace Private {
+  /**
+   * An object which holds a widget and its sort rank.
+   */
+  export interface IRankItem {
+    /**
+     * The widget for the item.
+     */
+    widget: Widget;
+
+    /**
+     * The sort rank of the widget.
+     */
+    rank: number;
+  }
+
+  /**
+   * A less-than comparison function for side bar rank items.
+   */
+  export function itemCmp(first: IRankItem, second: IRankItem): number {
+    return first.rank - second.rank;
+  }
+
+  /**
+   * A class which manages a panel and sorts its widgets by rank.
+   */
+  export class PanelHandler {
+    constructor() {
+      MessageLoop.installMessageHook(this._panel, this._panelChildHook);
+    }
+
+    /**
+     * Get the panel managed by the handler.
+     */
+    get panel(): Panel {
+      return this._panel;
+    }
+
+    /**
+     * Add a widget to the panel.
+     *
+     * If the widget is already added, it will be moved.
+     */
+    addWidget(widget: Widget, rank: number): void {
+      widget.parent = null;
+      const item = { widget, rank };
+      const index = ArrayExt.upperBound(this._items, item, Private.itemCmp);
+      ArrayExt.insert(this._items, index, item);
+      this._panel.insertWidget(index, widget);
+    }
+
+    /**
+     * A message hook for child add/remove messages on the main area dock panel.
+     */
+    private _panelChildHook = (
+      handler: IMessageHandler,
+      msg: Message
+    ): boolean => {
+      switch (msg.type) {
+        case 'child-added':
+          {
+            const widget = (msg as Widget.ChildMessage).child;
+            // If we already know about this widget, we're done
+            if (this._items.find((v) => v.widget === widget)) {
+              break;
+            }
+
+            // Otherwise, add to the end by default
+            const rank = this._items[this._items.length - 1].rank;
+            this._items.push({ widget, rank });
+          }
+          break;
+        case 'child-removed':
+          {
+            const widget = (msg as Widget.ChildMessage).child;
+            ArrayExt.removeFirstWhere(this._items, (v) => v.widget === widget);
+          }
+          break;
+        default:
+          break;
+      }
+      return true;
+    };
+
+    private _items = new Array<Private.IRankItem>();
+    private _panel = new Panel();
   }
 }

packages/voila/style/base.css

@@ -0,0 +1,18 @@
+body {
+  padding: 0 !important;
+}
+div#main {
+  height: 100vh;
+}
+div#voila-top-panel {
+  min-height: var(--jp-private-menubar-height);
+  display: flex;
+}
+div#voila-bottom-panel {
+  min-height: var(--jp-private-menubar-height);
+  display: flex;
+}
+div#rendered_cells {
+  padding: var(--jp-notebook-padding);
+  overflow: auto;
+}

packages/voila/style/index.css

@@ -0,0 +1 @@
+@import url('base.css');

packages/voila/style/index.js

@@ -4,3 +4,4 @@ import '@jupyterlab/apputils/style/index.js';
 import '@jupyterlab/rendermime/style/index.js';
 import '@jupyterlab/docregistry/style/index.js';
 import '@jupyterlab/markedparser-extension/style/index.js';
+import './base.css';

share/jupyter/voila/templates/reveal/index.html.j2

@@ -45,6 +45,9 @@
     .jp-mod-noOutputs.jp-mod-noInput {
       display: none;
     }
+    #rendered_cells {
+      padding: 0px!important
+    }
   </style>
 
   <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@fortawesome/fontawesome-free@^5/css/all.min.css" type="text/css" />

voila/configuration.py

@@ -190,3 +190,11 @@ def _valid_file_blacklist(self, proposal):
         config=True,
         help="""The list of disabled JupyterLab extensions, if `None`, all extensions are loaded""",
     )
+
+    extension_config = Dict(
+        None,
+        allow_none=True,
+        config=True,
+        help="""The dictionary of extension configuration, this dict is passed to the frontend
+        through the PageConfig""",
+    )

voila/handler.py

@@ -200,8 +200,7 @@ async def get_generator(self, path=None):
                     base_url=self.base_url,
                     settings=self.settings,
                     log=self.log,
-                    extension_allowlist=self.voila_configuration.extension_allowlist,
-                    extension_denylist=self.voila_configuration.extension_denylist,
+                    voila_configuration=self.voila_configuration,
                 ),
                 mathjax_config=mathjax_config,
                 mathjax_url=mathjax_url,

voila/notebook_renderer.py

@@ -143,7 +143,6 @@ async def initialize(self, **kwargs) -> None:
             contents_manager=self.contents_manager,  # for the image inlining
             theme=self.theme,  # we now have the theme in two places
             base_url=self.base_url,
-            page_config=self.page_config,
             show_margins=self.voila_configuration.show_margins,
             mathjax_url=mathjax_full_url,
         )

voila/tornado/treehandler.py

@@ -49,8 +49,7 @@ def allowed_content(content):
                 base_url=self.base_url,
                 settings=self.settings,
                 log=self.log,
-                extension_allowlist=self.voila_configuration.extension_allowlist,
-                extension_denylist=self.voila_configuration.extension_denylist,
+                voila_configuration=self.voila_configuration,
             )
             page_config["jupyterLabTheme"] = theme_arg