feat: configure sketchbook location without restart

Closes #1764
Closes #796
Closes #569
Closes #655

Signed-off-by: Akos Kitta <a.kitta@arduino.cc>

arduino-ide-extension/src/browser/arduino-ide-frontend-module.ts

@@ -343,6 +343,7 @@ import { DebugWidget } from '@theia/debug/lib/browser/view/debug-widget';
 import { DebugViewModel } from '@theia/debug/lib/browser/view/debug-view-model';
 import { DebugSessionWidget } from '@theia/debug/lib/browser/view/debug-session-widget';
 import { DebugConfigurationWidget } from '@theia/debug/lib/browser/view/debug-configuration-widget';
+import { ConfigServiceClient } from './config/config-service-client';
 
 export default new ContainerModule((bind, unbind, isBound, rebind) => {
   // Commands and toolbar items
@@ -404,6 +405,8 @@ export default new ContainerModule((bind, unbind, isBound, rebind) => {
       )
     )
     .inSingletonScope();
+  bind(ConfigServiceClient).toSelf().inSingletonScope();
+  bind(FrontendApplicationContribution).toService(ConfigServiceClient);
 
   // Boards service
   bind(BoardsService)

arduino-ide-extension/src/browser/config/config-service-client.ts

@@ -0,0 +1,106 @@
+import { FrontendApplicationContribution } from '@theia/core/lib/browser/frontend-application';
+import { FrontendApplicationStateService } from '@theia/core/lib/browser/frontend-application-state';
+import { DisposableCollection } from '@theia/core/lib/common/disposable';
+import { Emitter, Event } from '@theia/core/lib/common/event';
+import { MessageService } from '@theia/core/lib/common/message-service';
+import { deepClone } from '@theia/core/lib/common/objects';
+import URI from '@theia/core/lib/common/uri';
+import {
+  inject,
+  injectable,
+  postConstruct,
+} from '@theia/core/shared/inversify';
+import { ConfigService, ConfigState } from '../../common/protocol';
+import { NotificationCenter } from '../notification-center';
+
+@injectable()
+export class ConfigServiceClient implements FrontendApplicationContribution {
+  @inject(ConfigService)
+  private readonly delegate: ConfigService;
+  @inject(NotificationCenter)
+  private readonly notificationCenter: NotificationCenter;
+  @inject(FrontendApplicationStateService)
+  private readonly appStateService: FrontendApplicationStateService;
+  @inject(MessageService)
+  private readonly messageService: MessageService;
+
+  private readonly didChangeSketchDirUriEmitter = new Emitter<
+    URI | undefined
+  >();
+  private readonly didChangeDataDirUriEmitter = new Emitter<URI | undefined>();
+  private readonly toDispose = new DisposableCollection(
+    this.didChangeSketchDirUriEmitter,
+    this.didChangeDataDirUriEmitter
+  );
+
+  private config: ConfigState | undefined;
+
+  @postConstruct()
+  protected init(): void {
+    this.appStateService.reachedState('ready').then(async () => {
+      const config = await this.fetchConfig();
+      this.use(config);
+    });
+  }
+
+  onStart(): void {
+    this.notificationCenter.onConfigDidChange((config) => this.use(config));
+  }
+
+  onStop(): void {
+    this.toDispose.dispose();
+  }
+
+  get onDidChangeSketchDirUri(): Event<URI | undefined> {
+    return this.didChangeSketchDirUriEmitter.event;
+  }
+
+  get onDidChangeDataDirUri(): Event<URI | undefined> {
+    return this.didChangeDataDirUriEmitter.event;
+  }
+
+  async fetchConfig(): Promise<ConfigState> {
+    return this.delegate.getConfiguration();
+  }
+
+  /**
+   * CLI config related error messages if any.
+   */
+  tryGetMessages(): string[] | undefined {
+    return this.config?.messages;
+  }
+
+  /**
+   * `directories.user`
+   */
+  tryGetSketchDirUri(): URI | undefined {
+    return this.config?.config?.sketchDirUri
+      ? new URI(this.config?.config?.sketchDirUri)
+      : undefined;
+  }
+
+  /**
+   * `directories.data`
+   */
+  tryGetDataDirUri(): URI | undefined {
+    return this.config?.config?.dataDirUri
+      ? new URI(this.config?.config?.dataDirUri)
+      : undefined;
+  }
+
+  private use(config: ConfigState): void {
+    const oldConfig = deepClone(this.config);
+    this.config = config;
+    if (oldConfig?.config?.sketchDirUri !== this.config?.config?.sketchDirUri) {
+      this.didChangeSketchDirUriEmitter.fire(this.tryGetSketchDirUri());
+    }
+    if (oldConfig?.config?.dataDirUri !== this.config?.config?.dataDirUri) {
+      this.didChangeDataDirUriEmitter.fire(this.tryGetDataDirUri());
+    }
+    if (this.config.messages?.length) {
+      const message = this.config.messages.join(' ');
+      // toast the error later otherwise it might not show up in IDE2
+      setTimeout(() => this.messageService.error(message), 1_000);
+    }
+  }
+}

arduino-ide-extension/src/browser/contributions/add-zip-library.ts

@@ -2,7 +2,6 @@ import { inject, injectable } from '@theia/core/shared/inversify';
 import * as remote from '@theia/core/electron-shared/@electron/remote';
 import URI from '@theia/core/lib/common/uri';
 import { ConfirmDialog } from '@theia/core/lib/browser/dialogs';
-import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
 import { ArduinoMenus } from '../menu/arduino-menus';
 import { LibraryService, ResponseServiceClient } from '../../common/protocol';
 import { ExecuteWithProgress } from '../../common/protocol/progressible';
@@ -16,9 +15,6 @@ import { nls } from '@theia/core/lib/common';
 
 @injectable()
 export class AddZipLibrary extends SketchContribution {
-  @inject(EnvVariablesServer)
-  private readonly envVariableServer: EnvVariablesServer;
-
   @inject(ResponseServiceClient)
   private readonly responseService: ResponseServiceClient;
 

arduino-ide-extension/src/browser/contributions/archive-sketch.ts

@@ -1,7 +1,6 @@
 import { injectable } from '@theia/core/shared/inversify';
 import * as remote from '@theia/core/electron-shared/@electron/remote';
 import * as dateFormat from 'dateformat';
-import URI from '@theia/core/lib/common/uri';
 import { ArduinoMenus } from '../menu/arduino-menus';
 import {
   SketchContribution,
@@ -29,10 +28,7 @@ export class ArchiveSketch extends SketchContribution {
   }
 
   private async archiveSketch(): Promise<void> {
-    const [sketch, config] = await Promise.all([
+    const sketch = await this.sketchServiceClient.currentSketch();
-      this.sketchServiceClient.currentSketch(),
-      this.configService.getConfiguration(),
-    ]);
     if (!CurrentSketch.isValid(sketch)) {
       return;
     }
@@ -40,9 +36,9 @@ export class ArchiveSketch extends SketchContribution {
       new Date(),
       'yymmdd'
     )}a.zip`;
-    const defaultPath = await this.fileService.fsPath(
+    const defaultContainerUri = await this.defaultUri();
-      new URI(config.sketchDirUri).resolve(archiveBasename)
+    const defaultUri = defaultContainerUri.resolve(archiveBasename);
-    );
+    const defaultPath = await this.fileService.fsPath(defaultUri);
     const { filePath, canceled } = await remote.dialog.showSaveDialog(
       remote.getCurrentWindow(),
       {

arduino-ide-extension/src/browser/contributions/board-selection.ts

@@ -155,10 +155,7 @@ PID: ${PID}`;
     );
 
     // Ports submenu
-    const portsSubmenuPath = [
+    const portsSubmenuPath = ArduinoMenus.TOOLS__PORTS_SUBMENU;
-      ...ArduinoMenus.TOOLS__BOARD_SELECTION_GROUP,
-      '2_ports',
-    ];
     const portsSubmenuLabel = config.selectedPort?.address;
     this.menuModelRegistry.registerSubmenu(
       portsSubmenuPath,

arduino-ide-extension/src/browser/contributions/contribution.ts

@@ -12,6 +12,7 @@ import { MaybePromise } from '@theia/core/lib/common/types';
 import { LabelProvider } from '@theia/core/lib/browser/label-provider';
 import { EditorManager } from '@theia/editor/lib/browser/editor-manager';
 import { MessageService } from '@theia/core/lib/common/message-service';
+import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
 import { open, OpenerService } from '@theia/core/lib/browser/opener-service';
 
 import {
@@ -43,7 +44,6 @@ import {
 } from '../../common/protocol/sketches-service-client-impl';
 import {
   SketchesService,
-  ConfigService,
   FileSystemExt,
   Sketch,
   CoreService,
@@ -62,6 +62,7 @@ import { NotificationManager } from '../theia/messages/notifications-manager';
 import { MessageType } from '@theia/core/lib/common/message-service-protocol';
 import { WorkspaceService } from '../theia/workspace/workspace-service';
 import { MainMenuManager } from '../../common/main-menu-manager';
+import { ConfigServiceClient } from '../config/config-service-client';
 
 export {
   Command,
@@ -142,8 +143,8 @@ export abstract class SketchContribution extends Contribution {
   @inject(FileSystemExt)
   protected readonly fileSystemExt: FileSystemExt;
 
-  @inject(ConfigService)
+  @inject(ConfigServiceClient)
-  protected readonly configService: ConfigService;
+  protected readonly configService: ConfigServiceClient;
 
   @inject(SketchesService)
   protected readonly sketchService: SketchesService;
@@ -160,6 +161,9 @@ export abstract class SketchContribution extends Contribution {
   @inject(OutputChannelManager)
   protected readonly outputChannelManager: OutputChannelManager;
 
+  @inject(EnvVariablesServer)
+  protected readonly envVariableServer: EnvVariablesServer;
+
   protected async sourceOverride(): Promise<Record<string, string>> {
     const override: Record<string, string> = {};
     const sketch = await this.sketchServiceClient.currentSketch();
@@ -173,6 +177,25 @@ export abstract class SketchContribution extends Contribution {
     }
     return override;
   }
+
+  /**
+   * Defaults to `directories.user` if defined and not CLI config errors were detected.
+   * Otherwise, the URI of the user home directory.
+   */
+  protected async defaultUri(): Promise<URI> {
+    const errors = this.configService.tryGetMessages();
+    let defaultUri = this.configService.tryGetSketchDirUri();
+    if (!defaultUri || errors?.length) {
+      // Fall back to user home when the `directories.user` is not available or there are known CLI config errors
+      defaultUri = new URI(await this.envVariableServer.getHomeDirUri());
+    }
+    return defaultUri;
+  }
+
+  protected async defaultPath(): Promise<string> {
+    const defaultUri = await this.defaultUri();
+    return this.fileService.fsPath(defaultUri);
+  }
 }
 
 @injectable()

arduino-ide-extension/src/browser/contributions/examples.ts

@@ -29,6 +29,7 @@ import {
   CoreService,
 } from '../../common/protocol';
 import { nls } from '@theia/core/lib/common';
+import { unregisterSubmenu } from '../menu/arduino-menus';
 
 @injectable()
 export abstract class Examples extends SketchContribution {
@@ -36,7 +37,7 @@ export abstract class Examples extends SketchContribution {
   private readonly commandRegistry: CommandRegistry;
 
   @inject(MenuModelRegistry)
-  private readonly menuRegistry: MenuModelRegistry;
+  protected readonly menuRegistry: MenuModelRegistry;
 
   @inject(ExamplesService)
   protected readonly examplesService: ExamplesService;
@@ -47,6 +48,9 @@ export abstract class Examples extends SketchContribution {
   @inject(BoardsServiceProvider)
   protected readonly boardsServiceClient: BoardsServiceProvider;
 
+  @inject(NotificationCenter)
+  protected readonly notificationCenter: NotificationCenter;
+
   protected readonly toDispose = new DisposableCollection();
 
   protected override init(): void {
@@ -54,6 +58,12 @@ export abstract class Examples extends SketchContribution {
     this.boardsServiceClient.onBoardsConfigChanged(({ selectedBoard }) =>
       this.handleBoardChanged(selectedBoard)
     );
+    this.notificationCenter.onDidReinitialize(() =>
+      this.update({
+        board: this.boardsServiceClient.boardsConfig.selectedBoard,
+        // No force refresh. The core client was already refreshed.
+      })
+    );
   }
 
   // eslint-disable-next-line @typescript-eslint/no-unused-vars, unused-imports/no-unused-vars
@@ -120,6 +130,11 @@ export abstract class Examples extends SketchContribution {
         const { label } = sketchContainerOrPlaceholder;
         submenuPath = [...menuPath, label];
         this.menuRegistry.registerSubmenu(submenuPath, label, subMenuOptions);
+        this.toDispose.push(
+          Disposable.create(() =>
+            unregisterSubmenu(submenuPath, this.menuRegistry)
+          )
+        );
         sketches.push(...sketchContainerOrPlaceholder.sketches);
         children.push(...sketchContainerOrPlaceholder.children);
       } else {
@@ -239,9 +254,6 @@ export class BuiltInExamples extends Examples {
 
 @injectable()
 export class LibraryExamples extends Examples {
-  @inject(NotificationCenter)
-  private readonly notificationCenter: NotificationCenter;
-
   private readonly queue = new PQueue({ autoStart: true, concurrency: 1 });
 
   override onStart(): void {

arduino-ide-extension/src/browser/contributions/include-library.ts

@@ -53,6 +53,7 @@ export class IncludeLibrary extends SketchContribution {
     this.notificationCenter.onLibraryDidUninstall(() =>
       this.updateMenuActions()
     );
+    this.notificationCenter.onDidReinitialize(() => this.updateMenuActions());
   }
 
   override async onReady(): Promise<void> {

arduino-ide-extension/src/browser/contributions/open-sketch.ts

@@ -82,10 +82,7 @@ export class OpenSketch extends SketchContribution {
   }
 
   private async selectSketch(): Promise<Sketch | undefined> {
-    const config = await this.configService.getConfiguration();
+    const defaultPath = await this.defaultPath();
-    const defaultPath = await this.fileService.fsPath(
-      new URI(config.sketchDirUri)
-    );
     const { filePaths } = await remote.dialog.showOpenDialog(
       remote.getCurrentWindow(),
       {

arduino-ide-extension/src/browser/contributions/save-as-sketch.ts

@@ -58,10 +58,7 @@ export class SaveAsSketch extends SketchContribution {
       markAsRecentlyOpened,
     }: SaveAsSketch.Options = SaveAsSketch.Options.DEFAULT
   ): Promise<boolean> {
-    const [sketch, configuration] = await Promise.all([
+    const sketch = await this.sketchServiceClient.currentSketch();
-      this.sketchServiceClient.currentSketch(),
-      this.configService.getConfiguration(),
-    ]);
     if (!CurrentSketch.isValid(sketch)) {
       return false;
     }
@@ -72,7 +69,7 @@ export class SaveAsSketch extends SketchContribution {
     }
 
     const sketchUri = new URI(sketch.uri);
-    const sketchbookDirUri = new URI(configuration.sketchDirUri);
+    const sketchbookDirUri = await this.defaultUri();
     // If the sketch is temp, IDE2 proposes the default sketchbook folder URI.
     // If the sketch is not temp, but not contained in the default sketchbook folder, IDE2 proposes the default location.
     // Otherwise, it proposes the parent folder of the current sketch.

arduino-ide-extension/src/browser/contributions/sketchbook.ts

@@ -11,6 +11,7 @@ import { nls } from '@theia/core/lib/common/nls';
 export class Sketchbook extends Examples {
   override onStart(): void {
     this.sketchServiceClient.onSketchbookDidChange(() => this.update());
+    this.configService.onDidChangeSketchDirUri(() => this.update());
   }
 
   override async onReady(): Promise<void> {

arduino-ide-extension/src/browser/dialogs/settings/settings.ts

@@ -27,6 +27,7 @@ import {
 import { ElectronCommands } from '@theia/core/lib/electron-browser/menu/electron-menu-contribution';
 import { DefaultTheme } from '@theia/application-package/lib/application-props';
 import { FrontendApplicationConfigProvider } from '@theia/core/lib/browser/frontend-application-config-provider';
+import type { FileStat } from '@theia/filesystem/lib/common/files';
 
 export const WINDOW_SETTING = 'window';
 export const EDITOR_SETTING = 'editor';
@@ -171,7 +172,15 @@ export class SettingsService {
       this.preferenceService.get<boolean>(SHOW_ALL_FILES_SETTING, false),
       this.configService.getConfiguration(),
     ]);
-    const { additionalUrls, sketchDirUri, network } = cliConfig;
+    const {
+      config = {
+        additionalUrls: [],
+        sketchDirUri: '',
+        network: Network.Default(),
+      },
+    } = cliConfig;
+    const { additionalUrls, sketchDirUri, network } = config;
+
     const sketchbookPath = await this.fileService.fsPath(new URI(sketchDirUri));
     return {
       editorFontSize,
@@ -223,7 +232,11 @@ export class SettingsService {
     try {
       const { sketchbookPath, editorFontSize, themeId } = await settings;
       const sketchbookDir = await this.fileSystemExt.getUri(sketchbookPath);
-      if (!(await this.fileService.exists(new URI(sketchbookDir)))) {
+      let sketchbookStat: FileStat | undefined = undefined;
+      try {
+        sketchbookStat = await this.fileService.resolve(new URI(sketchbookDir));
+      } catch {}
+      if (!sketchbookStat || !sketchbookStat.isDirectory) {
         return nls.localize(
           'arduino/preferences/invalid.sketchbook.location',
           'Invalid sketchbook location: {0}',
@@ -274,10 +287,19 @@ export class SettingsService {
       network,
       sketchbookShowAllFiles,
     } = this._settings;
-    const [config, sketchDirUri] = await Promise.all([
+    const [cliConfig, sketchDirUri] = await Promise.all([
       this.configService.getConfiguration(),
       this.fileSystemExt.getUri(sketchbookPath),
     ]);
+    const { config } = cliConfig;
+    if (!config) {
+      // Do not check for any error messages. The config might has errors (such as invalid directories.user) right before saving the new values.
+      return nls.localize(
+        'arduino/preferences/noCliConfig',
+        'Could not load the CLI configuration'
+      );
+    }
+
     (config as any).additionalUrls = additionalUrls;
     (config as any).sketchDirUri = sketchDirUri;
     (config as any).network = network;

arduino-ide-extension/src/browser/local-cache/local-cache-fs-provider.ts

@@ -88,8 +88,25 @@ export class LocalCacheFsProvider
   }
 
   protected async init(fileService: FileService): Promise<void> {
-    const config = await this.configService.getConfiguration();
+    const { config } = await this.configService.getConfiguration();
-    this._localCacheRoot = new URI(config.dataDirUri);
+    // Any possible CLI config errors are ignored here. IDE2 does not verify the `directories.data` folder.
+    // If the data dir is accessible, IDE2 creates the cache folder for the remote sketches. Otherwise, it does not.
+    // The data folder can be configured outside of the IDE2, and the new data folder will be picked up with a
+    // subsequent IDE2 start.
+    if (!config?.dataDirUri) {
+      return; // the deferred promise will never resolve
+    }
+    const localCacheUri = new URI(config.dataDirUri);
+    try {
+      await fileService.access(localCacheUri);
+    } catch (err) {
+      console.error(
+        `'directories.data' location is inaccessible at ${config.dataDirUri}`,
+        err
+      );
+      return;
+    }
+    this._localCacheRoot = localCacheUri;
     for (const segment of ['RemoteSketchbook', 'ArduinoCloud']) {
       this._localCacheRoot = this._localCacheRoot.resolve(segment);
       await fileService.createFolder(this._localCacheRoot);

arduino-ide-extension/src/browser/menu/arduino-menus.ts

@@ -97,6 +97,11 @@ export namespace ArduinoMenus {
   export const TOOLS__BOARD_SELECTION_GROUP = [...TOOLS, '2_board_selection'];
   // Core settings, such as `Processor` and `Programmers` for the board and `Burn Bootloader`
   export const TOOLS__BOARD_SETTINGS_GROUP = [...TOOLS, '3_board_settings'];
+  // `Tool` > `Ports` (always visible https://github.com/arduino/arduino-ide/issues/655)
+  export const TOOLS__PORTS_SUBMENU = [
+    ...ArduinoMenus.TOOLS__BOARD_SELECTION_GROUP,
+    '2_ports',
+  ];
 
   // -- Help
   // `Getting Started`, `Environment`, `Troubleshooting`, etc.

arduino-ide-extension/src/browser/notification-center.ts

@@ -18,7 +18,7 @@ import {
   AttachedBoardsChangeEvent,
   BoardsPackage,
   LibraryPackage,
-  Config,
+  ConfigState,
   Sketch,
   ProgressMessage,
 } from '../common/protocol';
@@ -37,6 +37,7 @@ export class NotificationCenter
   @inject(FrontendApplicationStateService)
   private readonly appStateService: FrontendApplicationStateService;
 
+  private readonly didReinitializeEmitter = new Emitter<void>();
   private readonly indexUpdateDidCompleteEmitter =
     new Emitter<IndexUpdateDidCompleteParams>();
   private readonly indexUpdateWillStartEmitter =
@@ -47,9 +48,7 @@ export class NotificationCenter
     new Emitter<IndexUpdateDidFailParams>();
   private readonly daemonDidStartEmitter = new Emitter<string>();
   private readonly daemonDidStopEmitter = new Emitter<void>();
-  private readonly configDidChangeEmitter = new Emitter<{
+  private readonly configDidChangeEmitter = new Emitter<ConfigState>();
-    config: Config | undefined;
-  }>();
   private readonly platformDidInstallEmitter = new Emitter<{
     item: BoardsPackage;
   }>();
@@ -71,6 +70,7 @@ export class NotificationCenter
     new Emitter<FrontendApplicationState>();
 
   private readonly toDispose = new DisposableCollection(
+    this.didReinitializeEmitter,
     this.indexUpdateWillStartEmitter,
     this.indexUpdateDidProgressEmitter,
     this.indexUpdateDidCompleteEmitter,
@@ -85,6 +85,7 @@ export class NotificationCenter
     this.attachedBoardsDidChangeEmitter
   );
 
+  readonly onDidReinitialize = this.didReinitializeEmitter.event;
   readonly onIndexUpdateDidComplete = this.indexUpdateDidCompleteEmitter.event;
   readonly onIndexUpdateWillStart = this.indexUpdateWillStartEmitter.event;
   readonly onIndexUpdateDidProgress = this.indexUpdateDidProgressEmitter.event;
@@ -115,6 +116,10 @@ export class NotificationCenter
     this.toDispose.dispose();
   }
 
+  notifyDidReinitialize(): void {
+    this.didReinitializeEmitter.fire();
+  }
+
   notifyIndexUpdateWillStart(params: IndexUpdateWillStartParams): void {
     this.indexUpdateWillStartEmitter.fire(params);
   }
@@ -139,7 +144,7 @@ export class NotificationCenter
     this.daemonDidStopEmitter.fire();
   }
 
-  notifyConfigDidChange(event: { config: Config | undefined }): void {
+  notifyConfigDidChange(event: ConfigState): void {
     this.configDidChangeEmitter.fire(event);
   }
 

arduino-ide-extension/src/browser/theia/core/tab-bar-decorator.ts

@@ -1,30 +1,35 @@
 import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
 import URI from '@theia/core/lib/common/uri';
 import { Title, Widget } from '@theia/core/shared/@phosphor/widgets';
-import { ILogger } from '@theia/core/lib/common/logger';
 import { EditorWidget } from '@theia/editor/lib/browser';
 import { WidgetDecoration } from '@theia/core/lib/browser/widget-decoration';
 import { TabBarDecoratorService as TheiaTabBarDecoratorService } from '@theia/core/lib/browser/shell/tab-bar-decorator';
-import { ConfigService } from '../../../common/protocol/config-service';
+import { ConfigServiceClient } from '../../config/config-service-client';
+import { FrontendApplicationStateService } from '@theia/core/lib/browser/frontend-application-state';
 
 @injectable()
 export class TabBarDecoratorService extends TheiaTabBarDecoratorService {
-  @inject(ConfigService)
+  @inject(ConfigServiceClient)
-  protected readonly configService: ConfigService;
+  private readonly configService: ConfigServiceClient;
+  @inject(FrontendApplicationStateService)
+  private readonly appStateService: FrontendApplicationStateService;
 
-  @inject(ILogger)
+  private dataDirUri: URI | undefined;
-  protected readonly logger: ILogger;
-
-  protected dataDirUri: URI | undefined;
 
   @postConstruct()
   protected init(): void {
-    this.configService
+    const fireDidChange = () =>
-      .getConfiguration()
+      this.appStateService
-      .then(({ dataDirUri }) => (this.dataDirUri = new URI(dataDirUri)))
+        .reachedState('ready')
-      .catch((err) =>
+        .then(() => this.fireDidChangeDecorations());
-        this.logger.error(`Failed to determine the data directory: ${err}`)
+    this.dataDirUri = this.configService.tryGetDataDirUri();
-      );
+    this.configService.onDidChangeDataDirUri((dataDirUri) => {
+      this.dataDirUri = dataDirUri;
+      fireDidChange();
+    });
+    if (this.dataDirUri) {
+      fireDidChange();
+    }
   }
 
   override getDecorations(title: Title<Widget>): WidgetDecoration.Data[] {

arduino-ide-extension/src/browser/theia/markers/problem-manager.ts

@@ -5,31 +5,23 @@ import {
 } from '@theia/core/shared/inversify';
 import { Diagnostic } from '@theia/core/shared/vscode-languageserver-types';
 import URI from '@theia/core/lib/common/uri';
-import { ILogger } from '@theia/core';
 import { Marker } from '@theia/markers/lib/common/marker';
 import { ProblemManager as TheiaProblemManager } from '@theia/markers/lib/browser/problem/problem-manager';
-import { ConfigService } from '../../../common/protocol/config-service';
+import { ConfigServiceClient } from '../../config/config-service-client';
 import debounce = require('lodash.debounce');
 
 @injectable()
 export class ProblemManager extends TheiaProblemManager {
-  @inject(ConfigService)
+  @inject(ConfigServiceClient)
-  protected readonly configService: ConfigService;
+  private readonly configService: ConfigServiceClient;
 
-  @inject(ILogger)
+  private dataDirUri: URI | undefined;
-  protected readonly logger: ILogger;
-
-  protected dataDirUri: URI | undefined;
 
   @postConstruct()
   protected override init(): void {
     super.init();
-    this.configService
+    this.dataDirUri = this.configService.tryGetDataDirUri();
-      .getConfiguration()
+    this.configService.onDidChangeDataDirUri((uri) => (this.dataDirUri = uri));
-      .then(({ dataDirUri }) => (this.dataDirUri = new URI(dataDirUri)))
-      .catch((err) =>
-        this.logger.error(`Failed to determine the data directory: ${err}`)
-      );
   }
 
   override setMarkers(

arduino-ide-extension/src/browser/widgets/sketchbook/sketchbook-tree-model.ts

@@ -2,7 +2,7 @@ import { inject, injectable, postConstruct } from '@theia/core/shared/inversify'
 import URI from '@theia/core/lib/common/uri';
 import { FileNode, FileTreeModel } from '@theia/filesystem/lib/browser';
 import { FileService } from '@theia/filesystem/lib/browser/file-service';
-import { ConfigService } from '../../../common/protocol';
+import { ConfigServiceClient } from './../../config/config-service-client';
 import { SketchbookTree } from './sketchbook-tree';
 import { ArduinoPreferences } from '../../arduino-preferences';
 import {
@@ -36,8 +36,8 @@ export class SketchbookTreeModel extends FileTreeModel {
   @inject(CommandRegistry)
   public readonly commandRegistry: CommandRegistry;
 
-  @inject(ConfigService)
+  @inject(ConfigServiceClient)
-  protected readonly configService: ConfigService;
+  protected readonly configService: ConfigServiceClient;
 
   @inject(OpenerService)
   protected readonly openerService: OpenerService;
@@ -59,6 +59,12 @@ export class SketchbookTreeModel extends FileTreeModel {
     super.init();
     this.reportBusyProgress();
     this.initializeRoot();
+    this.toDispose.push(
+      this.configService.onDidChangeSketchDirUri(async () => {
+        await this.updateRoot();
+        this.selectRoot(this.root);
+      })
+    );
   }
 
   protected readonly pendingBusyProgress = new Map<string, Deferred<void>>();
@@ -121,6 +127,10 @@ export class SketchbookTreeModel extends FileTreeModel {
       return;
     }
     const root = this.root;
+    this.selectRoot(root);
+  }
+
+  private selectRoot(root: TreeNode | undefined) {
     if (CompositeTreeNode.is(root) && root.children.length === 1) {
       const child = root.children[0];
       if (
@@ -161,10 +171,12 @@ export class SketchbookTreeModel extends FileTreeModel {
   }
 
   protected async createRoot(): Promise<TreeNode | undefined> {
-    const config = await this.configService.getConfiguration();
+    const sketchDirUri = this.configService.tryGetSketchDirUri();
-    const rootFileStats = await this.fileService.resolve(
+    const errors = this.configService.tryGetMessages();
-      new URI(config.sketchDirUri)
+    if (!sketchDirUri || errors?.length) {
-    );
+      return undefined;
+    }
+    const rootFileStats = await this.fileService.resolve(sketchDirUri);
 
     if (this.workspaceService.opened && rootFileStats.children) {
       // filter out libraries and hardware

arduino-ide-extension/src/common/protocol/config-service.ts

@@ -6,10 +6,12 @@ export interface ConfigService {
   getVersion(): Promise<
     Readonly<{ version: string; commit: string; status?: string }>
   >;
-  getCliConfigFileUri(): Promise<string>;
+  getConfiguration(): Promise<ConfigState>;
-  getConfiguration(): Promise<Config>;
   setConfiguration(config: Config): Promise<void>;
 }
+export type ConfigState =
+  | { config: undefined; messages: string[] }
+  | { config: Config; messages?: string[] };
 
 export interface Daemon {
   readonly port: string | number;
@@ -119,7 +121,16 @@ export interface Config {
   readonly network: Network;
 }
 export namespace Config {
-  export function sameAs(left: Config, right: Config): boolean {
+  export function sameAs(
+    left: Config | undefined,
+    right: Config | undefined
+  ): boolean {
+    if (!left) {
+      return !right;
+    }
+    if (!right) {
+      return false;
+    }
     const leftUrls = left.additionalUrls.sort();
     const rightUrls = right.additionalUrls.sort();
     if (leftUrls.length !== rightUrls.length) {
@@ -150,7 +161,16 @@ export namespace AdditionalUrls {
   export function stringify(additionalUrls: AdditionalUrls): string {
     return additionalUrls.join(',');
   }
-  export function sameAs(left: AdditionalUrls, right: AdditionalUrls): boolean {
+  export function sameAs(
+    left: AdditionalUrls | undefined,
+    right: AdditionalUrls | undefined
+  ): boolean {
+    if (!left) {
+      return !right;
+    }
+    if (!right) {
+      return false;
+    }
     if (left.length !== right.length) {
       return false;
     }

arduino-ide-extension/src/common/protocol/notification-service.ts

@@ -2,7 +2,7 @@ import type { JsonRpcServer } from '@theia/core/lib/common/messaging/proxy-facto
 import type {
   AttachedBoardsChangeEvent,
   BoardsPackage,
-  Config,
+  ConfigState,
   ProgressMessage,
   Sketch,
   IndexType,
@@ -39,6 +39,11 @@ export interface IndexUpdateDidFailParams extends IndexUpdateParams {
 }
 
 export interface NotificationServiceClient {
+  // The cached state of the core client. Libraries, examples, etc. has been updated.
+  // This can happen without an index update. For example, changing the `directories.user` location.
+  // An index update always implicitly involves a re-initialization without notifying via this method.
+  notifyDidReinitialize(): void;
+
   // Index
   notifyIndexUpdateWillStart(params: IndexUpdateWillStartParams): void;
   notifyIndexUpdateDidProgress(progressMessage: ProgressMessage): void;
@@ -50,7 +55,7 @@ export interface NotificationServiceClient {
   notifyDaemonDidStop(): void;
 
   // CLI config
-  notifyConfigDidChange(event: { config: Config | undefined }): void;
+  notifyConfigDidChange(event: ConfigState): void;
 
   // Platforms
   notifyPlatformDidInstall(event: { item: BoardsPackage }): void;

arduino-ide-extension/src/common/protocol/sketches-service-client-impl.ts

@@ -3,13 +3,15 @@ import URI from '@theia/core/lib/common/uri';
 import { Emitter } from '@theia/core/lib/common/event';
 import { notEmpty } from '@theia/core/lib/common/objects';
 import { FileService } from '@theia/filesystem/lib/browser/file-service';
-import { MessageService } from '@theia/core/lib/common/message-service';
 import { FileChangeType } from '@theia/filesystem/lib/common/files';
 import { WorkspaceService } from '@theia/workspace/lib/browser/workspace-service';
-import { DisposableCollection } from '@theia/core/lib/common/disposable';
+import {
+  Disposable,
+  DisposableCollection,
+} from '@theia/core/lib/common/disposable';
 import { FrontendApplicationContribution } from '@theia/core/lib/browser/frontend-application';
-import { Sketch, SketchesService } from '../../common/protocol';
+import { Sketch, SketchesService } from '.';
-import { ConfigService } from './config-service';
+import { ConfigServiceClient } from '../../browser/config/config-service-client';
 import { SketchContainer, SketchesError, SketchRef } from './sketches-service';
 import {
   ARDUINO_CLOUD_FOLDER,
@@ -34,139 +36,143 @@ export class SketchesServiceClientImpl
   implements FrontendApplicationContribution
 {
   @inject(FileService)
-  protected readonly fileService: FileService;
+  private readonly fileService: FileService;
-
-  @inject(MessageService)
-  protected readonly messageService: MessageService;
-
   @inject(SketchesService)
-  protected readonly sketchService: SketchesService;
+  private readonly sketchService: SketchesService;
-
   @inject(WorkspaceService)
-  protected readonly workspaceService: WorkspaceService;
+  private readonly workspaceService: WorkspaceService;
-
+  @inject(ConfigServiceClient)
-  @inject(ConfigService)
+  private readonly configService: ConfigServiceClient;
-  protected readonly configService: ConfigService;
-
   @inject(FrontendApplicationStateService)
   private readonly appStateService: FrontendApplicationStateService;
 
-  protected sketches = new Map<string, SketchRef>();
+  private sketches = new Map<string, SketchRef>();
-  // TODO: rename this + event to the `onBlabla` pattern
+  private onSketchbookDidChangeEmitter = new Emitter<{
-  protected sketchbookDidChangeEmitter = new Emitter<{
     created: SketchRef[];
     removed: SketchRef[];
   }>();
-  readonly onSketchbookDidChange = this.sketchbookDidChangeEmitter.event;
+  readonly onSketchbookDidChange = this.onSketchbookDidChangeEmitter.event;
-  protected currentSketchDidChangeEmitter = new Emitter<CurrentSketch>();
+  private currentSketchDidChangeEmitter = new Emitter<CurrentSketch>();
   readonly onCurrentSketchDidChange = this.currentSketchDidChangeEmitter.event;
 
-  protected toDispose = new DisposableCollection(
+  private toDisposeBeforeWatchSketchbookDir = new DisposableCollection();
-    this.sketchbookDidChangeEmitter,
+  private toDispose = new DisposableCollection(
-    this.currentSketchDidChangeEmitter
+    this.onSketchbookDidChangeEmitter,
+    this.currentSketchDidChangeEmitter,
+    this.toDisposeBeforeWatchSketchbookDir
   );
 
   private _currentSketch: CurrentSketch | undefined;
   private currentSketchLoaded = new Deferred<CurrentSketch>();
 
   onStart(): void {
-    this.configService.getConfiguration().then(({ sketchDirUri }) => {
+    const sketchDirUri = this.configService.tryGetSketchDirUri();
-      this.sketchService
+    this.watchSketchbookDir(sketchDirUri);
-        .getSketches({ uri: sketchDirUri })
+    const refreshCurrentSketch = async () => {
-        .then((container) => {
+      const currentSketch = await this.loadCurrentSketch();
-          const sketchbookUri = new URI(sketchDirUri);
+      this.useCurrentSketch(currentSketch);
-          for (const sketch of SketchContainer.toArray(container)) {
+    };
-            this.sketches.set(sketch.uri, sketch);
+    this.toDispose.push(
-          }
+      this.configService.onDidChangeSketchDirUri((sketchDirUri) => {
-          this.toDispose.push(
+        this.watchSketchbookDir(sketchDirUri);
-            // Watch changes in the sketchbook to update `File` > `Sketchbook` menu items.
+        refreshCurrentSketch();
-            this.fileService.watch(new URI(sketchDirUri), {
+      })
-              recursive: true,
+    );
-              excludes: [],
-            })
-          );
-          this.toDispose.push(
-            this.fileService.onDidFilesChange(async (event) => {
-              for (const { type, resource } of event.changes) {
-                // The file change events have higher precedence in the current sketch over the sketchbook.
-                if (
-                  CurrentSketch.isValid(this._currentSketch) &&
-                  new URI(this._currentSketch.uri).isEqualOrParent(resource)
-                ) {
-                  // https://github.com/arduino/arduino-ide/pull/1351#pullrequestreview-1086666656
-                  // On a sketch file rename, the FS watcher will contain two changes:
-                  //  - Deletion of the original file,
-                  //  - Update of the new file,
-                  // Hence, `UPDATE` events must be processed but only and if only there is a `DELETED` change in the same event.
-                  // Otherwise, IDE2 would ask CLI to reload the sketch content on every save event in IDE2.
-                  if (
-                    type === FileChangeType.UPDATED &&
-                    event.changes.length === 1
-                  ) {
-                    // If the event contains only one `UPDATE` change, it cannot be a rename.
-                    return;
-                  }
-
-                  let reloadedSketch: Sketch | undefined = undefined;
-                  try {
-                    reloadedSketch = await this.sketchService.loadSketch(
-                      this._currentSketch.uri
-                    );
-                  } catch (err) {
-                    if (!SketchesError.NotFound.is(err)) {
-                      throw err;
-                    }
-                  }
-
-                  if (!reloadedSketch) {
-                    return;
-                  }
-
-                  if (!Sketch.sameAs(this._currentSketch, reloadedSketch)) {
-                    this.useCurrentSketch(reloadedSketch, true);
-                  }
-                  return;
-                }
-                // We track main sketch files changes only. // TODO: check sketch folder changes. One can rename the folder without renaming the `.ino` file.
-                if (sketchbookUri.isEqualOrParent(resource)) {
-                  if (Sketch.isSketchFile(resource)) {
-                    if (type === FileChangeType.ADDED) {
-                      try {
-                        const toAdd = await this.sketchService.loadSketch(
-                          resource.parent.toString()
-                        );
-                        if (!this.sketches.has(toAdd.uri)) {
-                          console.log(
-                            `New sketch '${toAdd.name}' was created in sketchbook '${sketchDirUri}'.`
-                          );
-                          this.sketches.set(toAdd.uri, toAdd);
-                          this.fireSoon(toAdd, 'created');
-                        }
-                      } catch {}
-                    } else if (type === FileChangeType.DELETED) {
-                      const uri = resource.parent.toString();
-                      const toDelete = this.sketches.get(uri);
-                      if (toDelete) {
-                        console.log(
-                          `Sketch '${toDelete.name}' was removed from sketchbook '${sketchbookUri}'.`
-                        );
-                        this.sketches.delete(uri);
-                        this.fireSoon(toDelete, 'removed');
-                      }
-                    }
-                  }
-                }
-              }
-            })
-          );
-        });
-    });
     this.appStateService
       .reachedState('started_contributions')
-      .then(async () => {
+      .then(refreshCurrentSketch);
-        const currentSketch = await this.loadCurrentSketch();
+  }
-        this.useCurrentSketch(currentSketch);
+
-      });
+  private async watchSketchbookDir(
+    sketchDirUri: URI | undefined
+  ): Promise<void> {
+    this.toDisposeBeforeWatchSketchbookDir.dispose();
+    if (!sketchDirUri) {
+      return;
+    }
+    const container = await this.sketchService.getSketches({
+      uri: sketchDirUri.toString(),
+    });
+    for (const sketch of SketchContainer.toArray(container)) {
+      this.sketches.set(sketch.uri, sketch);
+    }
+    this.toDisposeBeforeWatchSketchbookDir.pushAll([
+      Disposable.create(() => this.sketches.clear()),
+      // Watch changes in the sketchbook to update `File` > `Sketchbook` menu items.
+      this.fileService.watch(sketchDirUri, {
+        recursive: true,
+        excludes: [],
+      }),
+      this.fileService.onDidFilesChange(async (event) => {
+        for (const { type, resource } of event.changes) {
+          // The file change events have higher precedence in the current sketch over the sketchbook.
+          if (
+            CurrentSketch.isValid(this._currentSketch) &&
+            new URI(this._currentSketch.uri).isEqualOrParent(resource)
+          ) {
+            // https://github.com/arduino/arduino-ide/pull/1351#pullrequestreview-1086666656
+            // On a sketch file rename, the FS watcher will contain two changes:
+            //  - Deletion of the original file,
+            //  - Update of the new file,
+            // Hence, `UPDATE` events must be processed but only and if only there is a `DELETED` change in the same event.
+            // Otherwise, IDE2 would ask CLI to reload the sketch content on every save event in IDE2.
+            if (type === FileChangeType.UPDATED && event.changes.length === 1) {
+              // If the event contains only one `UPDATE` change, it cannot be a rename.
+              return;
+            }
+
+            let reloadedSketch: Sketch | undefined = undefined;
+            try {
+              reloadedSketch = await this.sketchService.loadSketch(
+                this._currentSketch.uri
+              );
+            } catch (err) {
+              if (!SketchesError.NotFound.is(err)) {
+                throw err;
+              }
+            }
+
+            if (!reloadedSketch) {
+              return;
+            }
+
+            if (!Sketch.sameAs(this._currentSketch, reloadedSketch)) {
+              this.useCurrentSketch(reloadedSketch, true);
+            }
+            return;
+          }
+          // We track main sketch files changes only. // TODO: check sketch folder changes. One can rename the folder without renaming the `.ino` file.
+          if (sketchDirUri.isEqualOrParent(resource)) {
+            if (Sketch.isSketchFile(resource)) {
+              if (type === FileChangeType.ADDED) {
+                try {
+                  const toAdd = await this.sketchService.loadSketch(
+                    resource.parent.toString()
+                  );
+                  if (!this.sketches.has(toAdd.uri)) {
+                    console.log(
+                      `New sketch '${toAdd.name}' was created in sketchbook '${sketchDirUri}'.`
+                    );
+                    this.sketches.set(toAdd.uri, toAdd);
+                    this.fireSoon(toAdd, 'created');
+                  }
+                } catch {}
+              } else if (type === FileChangeType.DELETED) {
+                const uri = resource.parent.toString();
+                const toDelete = this.sketches.get(uri);
+                if (toDelete) {
+                  console.log(
+                    `Sketch '${toDelete.name}' was removed from sketchbook '${sketchDirUri}'.`
+                  );
+                  this.sketches.delete(uri);
+                  this.fireSoon(toDelete, 'removed');
+                }
+              }
+            }
+          }
+        }
+      }),
+    ]);
   }
 
   private useCurrentSketch(
@@ -249,7 +255,7 @@ export class SketchesServiceClientImpl
           event.removed.push(sketch);
         }
       }
-      this.sketchbookDidChangeEmitter.fire(event);
+      this.onSketchbookDidChangeEmitter.fire(event);
       this.bufferedSketchbookEvents.length = 0;
     }, 100);
   }

arduino-ide-extension/src/electron-browser/theia/core/electron-main-menu-factory.ts

@@ -180,7 +180,7 @@ export class ElectronMainMenuFactory extends TheiaElectronMainMenuFactory {
 
     if (
       CompoundMenuNode.is(menu) &&
-      menu.children.length &&
+      this.visibleSubmenu(menu) && // customization for #569 and #655
       this.undefinedOrMatch(menu.when, options.context)
     ) {
       const role = CompoundMenuNode.getRole(menu);
@@ -193,10 +193,17 @@ export class ElectronMainMenuFactory extends TheiaElectronMainMenuFactory {
         this.fillMenuTemplate(myItems, child, args, options)
       );
       if (myItems.length === 0) {
-        return parentItems;
+        // customization for #569 and #655
+        if (!this.visibleLeafSubmenu(menu)) {
+          return parentItems;
+        }
       }
       if (role === CompoundMenuNodeRole.Submenu) {
-        parentItems.push({ label: menu.label, submenu: myItems });
+        parentItems.push({
+          label: menu.label,
+          submenu: myItems,
+          enabled: !this.visibleLeafSubmenu(menu), // customization for #569 and #655
+        });
       } else if (role === CompoundMenuNodeRole.Group && menu.id !== 'inline') {
         if (
           parentItems.length &&
@@ -278,4 +285,31 @@ export class ElectronMainMenuFactory extends TheiaElectronMainMenuFactory {
     }
     return parentItems;
   }
+
+  /**
+   * `true` if either has at least `children`, or was forced to be visible.
+   */
+  private visibleSubmenu(node: MenuNode & CompoundMenuNode): boolean {
+    return node.children.length > 0 || this.visibleLeafSubmenu(node);
+  }
+
+  /**
+   * The node is a visible submenu if is a compound node but has zero children.
+   */
+  private visibleLeafSubmenu(node: MenuNode): boolean {
+    if (CompoundMenuNode.is(node)) {
+      return (
+        node.children.length === 0 &&
+        AlwaysVisibleSubmenus.findIndex(
+          (menuPath) => menuPath[menuPath.length - 1] === node.id
+        ) >= 0
+      );
+    }
+    return false;
+  }
 }
+
+const AlwaysVisibleSubmenus: MenuPath[] = [
+  ArduinoMenus.TOOLS__PORTS_SUBMENU, // #655
+  ArduinoMenus.FILE__SKETCHBOOK_SUBMENU, // #569
+];

arduino-ide-extension/src/node/clang-formatter.ts

@@ -79,9 +79,12 @@ export class ClangFormatter implements Formatter {
     return `-style="${style(toClangOptions(options))}"`;
   }
 
-  private async dataDirPath(): Promise<string> {
+  private async dataDirPath(): Promise<string | undefined> {
-    const { dataDirUri } = await this.configService.getConfiguration();
+    const { config } = await this.configService.getConfiguration();
-    return FileUri.fsPath(dataDirUri);
+    if (!config?.dataDirUri) {
+      return undefined;
+    }
+    return FileUri.fsPath(config.dataDirUri);
   }
 
   private async configDirPath(): Promise<string> {
@@ -90,9 +93,13 @@ export class ClangFormatter implements Formatter {
   }
 
   private async clangConfigPath(
-    folderUri: MaybePromise<string>
+    folderUri: MaybePromise<string | undefined>
   ): Promise<string | undefined> {
-    const folderPath = FileUri.fsPath(await folderUri);
+    const uri = await folderUri;
+    if (!uri) {
+      return undefined;
+    }
+    const folderPath = FileUri.fsPath(uri);
     const clangFormatPath = join(folderPath, ClangFormatFile);
     try {
       await fs.access(clangFormatPath, constants.R_OK);

arduino-ide-extension/src/node/config-service-impl.ts

@@ -13,6 +13,7 @@ import {
   Config,
   NotificationServiceServer,
   Network,
+  ConfigState,
 } from '../common/protocol';
 import { spawnCommand } from './exec-util';
 import {
@@ -25,7 +26,7 @@ import { ArduinoDaemonImpl } from './arduino-daemon-impl';
 import { DefaultCliConfig, CLI_CONFIG } from './cli-config';
 import { Deferred } from '@theia/core/lib/common/promise-util';
 import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
-import { deepClone } from '@theia/core';
+import { deepClone, nls } from '@theia/core';
 import { ErrnoException } from './utils/errors';
 
 const deepmerge = require('deepmerge');
@@ -36,46 +37,38 @@ export class ConfigServiceImpl
 {
   @inject(ILogger)
   @named('config')
-  protected readonly logger: ILogger;
+  private readonly logger: ILogger;
 
   @inject(EnvVariablesServer)
-  protected readonly envVariablesServer: EnvVariablesServer;
+  private readonly envVariablesServer: EnvVariablesServer;
 
   @inject(ArduinoDaemonImpl)
-  protected readonly daemon: ArduinoDaemonImpl;
+  private readonly daemon: ArduinoDaemonImpl;
 
   @inject(NotificationServiceServer)
-  protected readonly notificationService: NotificationServiceServer;
+  private readonly notificationService: NotificationServiceServer;
 
-  protected config: Config;
+  private config: ConfigState = {
-  protected cliConfig: DefaultCliConfig | undefined;
+    config: undefined,
-  protected ready = new Deferred<void>();
+    messages: ['uninitialized'],
-  protected readonly configChangeEmitter = new Emitter<Config>();
+  };
+  private cliConfig: DefaultCliConfig | undefined;
+  private ready = new Deferred<void>();
+  private readonly configChangeEmitter = new Emitter<{
+    oldState: ConfigState;
+    newState: ConfigState;
+  }>();
 
   onStart(): void {
-    this.loadCliConfig().then(async (cliConfig) => {
+    this.initConfig();
-      this.cliConfig = cliConfig;
-      if (this.cliConfig) {
-        const [config] = await Promise.all([
-          this.mapCliConfigToAppConfig(this.cliConfig),
-          this.ensureUserDirExists(this.cliConfig),
-        ]);
-        if (config) {
-          this.config = config;
-          this.ready.resolve();
-          return;
-        }
-      }
-      this.fireInvalidConfig();
-    });
   }
 
-  async getCliConfigFileUri(): Promise<string> {
+  private async getCliConfigFileUri(): Promise<string> {
     const configDirUri = await this.envVariablesServer.getConfigDirUri();
     return new URI(configDirUri).resolve(CLI_CONFIG).toString();
   }
 
-  async getConfiguration(): Promise<Config> {
+  async getConfiguration(): Promise<ConfigState> {
     await this.ready.promise;
     return { ...this.config };
   }
@@ -83,9 +76,10 @@ export class ConfigServiceImpl
   // Used by frontend to update the config.
   async setConfiguration(config: Config): Promise<void> {
     await this.ready.promise;
-    if (Config.sameAs(this.config, config)) {
+    if (Config.sameAs(this.config.config, config)) {
       return;
     }
+    const oldConfigState = deepClone(this.config);
     let copyDefaultCliConfig: DefaultCliConfig | undefined = deepClone(
       this.cliConfig
     );
@@ -110,16 +104,30 @@ export class ConfigServiceImpl
     await this.updateDaemon(port, copyDefaultCliConfig);
     await this.writeDaemonState(port);
 
-    this.config = deepClone(config);
+    this.config.config = deepClone(config);
     this.cliConfig = copyDefaultCliConfig;
-    this.fireConfigChanged(this.config);
+    try {
+      await this.validateCliConfig(this.cliConfig);
+      delete this.config.messages;
+      this.fireConfigChanged(oldConfigState, this.config);
+    } catch (err) {
+      if (err instanceof InvalidConfigError) {
+        this.config.messages = err.errors;
+        this.fireConfigChanged(oldConfigState, this.config);
+      } else {
+        throw err;
+      }
+    }
   }
 
   get cliConfiguration(): DefaultCliConfig | undefined {
     return this.cliConfig;
   }
 
-  get onConfigChange(): Event<Config> {
+  get onConfigChange(): Event<{
+    oldState: ConfigState;
+    newState: ConfigState;
+  }> {
     return this.configChangeEmitter.event;
   }
 
@@ -129,9 +137,42 @@ export class ConfigServiceImpl
     return this.daemon.getVersion();
   }
 
-  protected async loadCliConfig(
+  private async initConfig(): Promise<void> {
+    try {
+      const cliConfig = await this.loadCliConfig();
+      this.cliConfig = cliConfig;
+      const [config] = await Promise.all([
+        this.mapCliConfigToAppConfig(this.cliConfig),
+        this.ensureUserDirExists(this.cliConfig).catch((reason) => {
+          if (reason instanceof Error) {
+            this.logger.warn(
+              `Could not ensure user directory existence: ${this.cliConfig?.directories.user}`,
+              reason
+            );
+          }
+          // NOOP. Try to create the folder if missing but swallow any errors.
+          // The validation will take care of the missing location handling.
+        }),
+      ]);
+      this.config.config = config;
+      await this.validateCliConfig(this.cliConfig);
+      delete this.config.messages;
+      if (config) {
+        this.ready.resolve();
+        return;
+      }
+    } catch (err: unknown) {
+      this.logger.error('Failed to initialize the CLI configuration.', err);
+      if (err instanceof InvalidConfigError) {
+        this.config.messages = err.errors;
+        this.ready.resolve();
+      }
+    }
+  }
+
+  private async loadCliConfig(
     initializeIfAbsent = true
-  ): Promise<DefaultCliConfig | undefined> {
+  ): Promise<DefaultCliConfig> {
     const cliConfigFileUri = await this.getCliConfigFileUri();
     const cliConfigPath = FileUri.fsPath(cliConfigFileUri);
     try {
@@ -157,7 +198,7 @@ export class ConfigServiceImpl
     }
   }
 
-  protected async getFallbackCliConfig(): Promise<DefaultCliConfig> {
+  private async getFallbackCliConfig(): Promise<DefaultCliConfig> {
     const cliPath = await this.daemon.getExecPath();
     const rawJson = await spawnCommand(`"${cliPath}"`, [
       'config',
@@ -168,7 +209,7 @@ export class ConfigServiceImpl
     return JSON.parse(rawJson);
   }
 
-  protected async initCliConfigTo(fsPathToDir: string): Promise<void> {
+  private async initCliConfigTo(fsPathToDir: string): Promise<void> {
     const cliPath = await this.daemon.getExecPath();
     await spawnCommand(`"${cliPath}"`, [
       'config',
@@ -178,7 +219,7 @@ export class ConfigServiceImpl
     ]);
   }
 
-  protected async mapCliConfigToAppConfig(
+  private async mapCliConfigToAppConfig(
     cliConfig: DefaultCliConfig
   ): Promise<Config> {
     const { directories, locale = 'en' } = cliConfig;
@@ -199,16 +240,45 @@ export class ConfigServiceImpl
     };
   }
 
-  protected fireConfigChanged(config: Config): void {
+  private fireConfigChanged(
-    this.configChangeEmitter.fire(config);
+    oldState: ConfigState,
-    this.notificationService.notifyConfigDidChange({ config });
+    newState: ConfigState
+  ): void {
+    this.configChangeEmitter.fire({ oldState, newState });
+    this.notificationService.notifyConfigDidChange(newState);
   }
 
-  protected fireInvalidConfig(): void {
+  private async validateCliConfig(config: DefaultCliConfig): Promise<void> {
-    this.notificationService.notifyConfigDidChange({ config: undefined });
+    const errors: string[] = [];
+    errors.push(...(await this.checkAccessible(config)));
+    if (errors.length) {
+      throw new InvalidConfigError(errors);
+    }
   }
 
-  protected async updateDaemon(
+  private async checkAccessible({
+    directories,
+  }: DefaultCliConfig): Promise<string[]> {
+    try {
+      await fs.readdir(directories.user);
+      return [];
+    } catch (err) {
+      console.error(
+        `Check accessible failed for input: ${directories.user}`,
+        err
+      );
+      return [
+        nls.localize(
+          'arduino/configuration/cli/inaccessibleDirectory',
+          "Could not access the sketchbook location at '{0}': {1}",
+          directories.user,
+          String(err)
+        ),
+      ];
+    }
+  }
+
+  private async updateDaemon(
     port: string | number,
     config: DefaultCliConfig
   ): Promise<void> {
@@ -216,7 +286,7 @@ export class ConfigServiceImpl
     const req = new MergeRequest();
     const json = JSON.stringify(config, null, 2);
     req.setJsonData(json);
-    console.log(`Updating daemon with 'data': ${json}`);
+    this.logger.info(`Updating daemon with 'data': ${json}`);
     return new Promise<void>((resolve, reject) => {
       client.merge(req, (error) => {
         try {
@@ -232,7 +302,7 @@ export class ConfigServiceImpl
     });
   }
 
-  protected async writeDaemonState(port: string | number): Promise<void> {
+  private async writeDaemonState(port: string | number): Promise<void> {
     const client = this.createClient(port);
     const req = new WriteRequest();
     const cliConfigUri = await this.getCliConfigFileUri();
@@ -273,3 +343,13 @@ export class ConfigServiceImpl
     await fs.mkdir(cliConfig.directories.user, { recursive: true });
   }
 }
+
+class InvalidConfigError extends Error {
+  constructor(readonly errors: string[]) {
+    super('InvalidConfigError:\n - ' + errors.join('\n - '));
+    if (!errors.length) {
+      throw new Error("Illegal argument: 'messages'. It must not be empty.");
+    }
+    Object.setPrototypeOf(this, InvalidConfigError.prototype);
+  }
+}

arduino-ide-extension/src/node/core-client-provider.ts

@@ -25,6 +25,7 @@ import {
   IndexUpdateDidFailParams,
   IndexUpdateWillStartParams,
   NotificationServiceServer,
+  AdditionalUrls,
 } from '../common/protocol';
 import { Deferred } from '@theia/core/lib/common/promise-util';
 import {
@@ -75,9 +76,27 @@ export class CoreClientProvider {
     });
     this.daemon.onDaemonStarted((port) => this.create(port));
     this.daemon.onDaemonStopped(() => this.closeClient());
-    this.configService.onConfigChange(
+    this.configService.onConfigChange(async ({ oldState, newState }) => {
-      () => this.client.then((client) => this.updateIndex(client, ['platform'])) // Assuming 3rd party URL changes. No library index update is required.
+      if (
-    );
+        !AdditionalUrls.sameAs(
+          oldState.config?.additionalUrls,
+          newState.config?.additionalUrls
+        )
+      ) {
+        const client = await this.client;
+        this.updateIndex(client, ['platform']);
+      } else if (
+        !!newState.config?.sketchDirUri &&
+        oldState.config?.sketchDirUri !== newState.config.sketchDirUri
+      ) {
+        // If the sketchbook location has changed, the custom libraries has changed.
+        // Reinitialize the core client and fire an event so that the frontend can refresh.
+        // https://github.com/arduino/arduino-ide/issues/796 (see the file > examples and sketch > include examples)
+        const client = await this.client;
+        await this.initInstance(client);
+        this.notificationService.notifyDidReinitialize();
+      }
+    });
   }
 
   get tryGetClient(): CoreClientProvider.Client | undefined {

arduino-ide-extension/src/node/notification-service-server.ts

@@ -5,7 +5,7 @@ import type {
   AttachedBoardsChangeEvent,
   BoardsPackage,
   LibraryPackage,
-  Config,
+  ConfigState,
   Sketch,
   ProgressMessage,
   IndexUpdateWillStartParams,
@@ -19,6 +19,10 @@ export class NotificationServiceServerImpl
 {
   private readonly clients: NotificationServiceClient[] = [];
 
+  notifyDidReinitialize(): void {
+    this.clients.forEach((client) => client.notifyDidReinitialize());
+  }
+
   notifyIndexUpdateWillStart(params: IndexUpdateWillStartParams): void {
     this.clients.forEach((client) => client.notifyIndexUpdateWillStart(params));
   }
@@ -69,7 +73,7 @@ export class NotificationServiceServerImpl
     );
   }
 
-  notifyConfigDidChange(event: { config: Config | undefined }): void {
+  notifyConfigDidChange(event: ConfigState): void {
     this.clients.forEach((client) => client.notifyConfigDidChange(event));
   }
 

arduino-ide-extension/src/node/sketches-service-impl.ts

@@ -80,6 +80,15 @@ export class SketchesServiceImpl
 
   async getSketches({ uri }: { uri?: string }): Promise<SketchContainer> {
     const root = await this.root(uri);
+    if (!root) {
+      this.logger.warn(`Could not derive sketchbook root from ${uri}.`);
+      return SketchContainer.create('');
+    }
+    const exists = await this.exists(root);
+    if (!exists) {
+      this.logger.warn(`Sketchbook root ${root} does not exist.`);
+      return SketchContainer.create('');
+    }
     const pathToAllSketchFiles = await new Promise<string[]>(
       (resolve, reject) => {
         glob(
@@ -179,13 +188,23 @@ export class SketchesServiceImpl
     return container;
   }
 
-  private async root(uri?: string | undefined): Promise<string> {
+  private async root(uri?: string | undefined): Promise<string | undefined> {
-    return FileUri.fsPath(uri ?? (await this.sketchbookUri()));
+    if (uri) {
+      return FileUri.fsPath(uri);
+    }
+    const sketchbookUri = await this.sketchbookUri();
+    if (sketchbookUri) {
+      return FileUri.fsPath(sketchbookUri);
+    }
+    return undefined;
   }
 
-  private async sketchbookUri(): Promise<string> {
+  private async sketchbookUri(): Promise<string | undefined> {
-    const { sketchDirUri } = await this.configService.getConfiguration();
+    const { config, messages } = await this.configService.getConfiguration();
-    return sketchDirUri;
+    if (!config?.sketchDirUri || messages?.length) {
+      return undefined;
+    }
+    return config.sketchDirUri;
   }
 
   async loadSketch(uri: string): Promise<SketchWithDetails> {
@@ -454,8 +473,10 @@ export class SketchesServiceImpl
     const sketchBaseName = `sketch_${
       monthNames[today.getMonth()]
     }${today.getDate()}`;
-    const config = await this.configService.getConfiguration();
+    const { config } = await this.configService.getConfiguration();
-    const sketchbookPath = FileUri.fsPath(config.sketchDirUri);
+    const sketchbookPath = config?.sketchDirUri
+      ? FileUri.fsPath(config?.sketchDirUri)
+      : os.homedir();
     let sketchName: string | undefined;
 
     // If it's another day, reset the count of sketches created today

i18n/en.json

@@ -157,6 +157,11 @@
       "uninstallMsg": "Do you want to uninstall {0}?",
       "version": "Version {0}"
     },
+    "configuration": {
+      "cli": {
+        "inaccessibleDirectory": "Could not access the sketchbook location at '{0}': {1}"
+      }
+    },
     "contributions": {
       "addFile": "Add File",
       "fileAdded": "One file added to the sketch.",
@@ -352,6 +357,7 @@
       "manualProxy": "Manual proxy configuration",
       "network": "Network",
       "newSketchbookLocation": "Select new sketchbook location",
+      "noCliConfig": "Could not load the CLI configuration",
       "noProxy": "No proxy",
       "proxySettings": {
         "hostname": "Host name",