fixup.

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

Author: Akos Kitta

Diff for: arduino-ide-extension/src/node/board-discovery.ts

@@ -14,13 +14,14 @@ import {
   AvailablePorts,
   AttachedBoardsChangeEvent,
 } from '../common/protocol';
-import { Emitter } from '@theia/core/lib/common/event';
+import { Emitter, Event } from '@theia/core/lib/common/event';
 import { DisposableCollection } from '@theia/core/lib/common/disposable';
 import { Disposable } from '@theia/core/shared/vscode-languageserver-protocol';
 import { ArduinoCoreServiceClient } from './cli-protocol/cc/arduino/cli/commands/v1/commands_grpc_pb';
 import { v4 } from 'uuid';
 import { ServiceError } from './service-error';
 import { BackendApplicationContribution } from '@theia/core/lib/node';
+import { Deferred } from '@theia/core/lib/common/promise-util';
 
 type Duplex = ClientDuplexStream<BoardListWatchRequest, BoardListWatchResponse>;
 interface StreamWrapper extends Disposable {
@@ -30,7 +31,8 @@ interface StreamWrapper extends Disposable {
 
 /**
  * Singleton service for tracking the available ports and board and broadcasting the
- * changes to all connected frontend instances. \
+ * changes to all connected frontend instances.
+ *
  * Unlike other services, this is not connection scoped.
  */
 @injectable()
@@ -45,16 +47,16 @@ export class BoardDiscovery
   @inject(NotificationServiceServer)
   private readonly notificationService: NotificationServiceServer;
 
-  // Used to know if the board watch process is already running to avoid
-  // starting it multiple times
-  private watching: boolean;
+  private watching: Deferred<void> | undefined;
+  private stopping: Deferred<void> | undefined;
   private wrapper: StreamWrapper | undefined;
   private readonly onStreamDidEndEmitter = new Emitter<void>(); // sent from the CLI when the discovery process is killed for example after the indexes update and the core client re-initialization.
   private readonly onStreamDidCancelEmitter = new Emitter<void>(); // when the watcher is canceled by the IDE2
   private readonly toDisposeOnStopWatch = new DisposableCollection();
 
   /**
    * Keys are the `address` of the ports.
+   *
    * The `protocol` is ignored because the board detach event does not carry the protocol information,
    * just the address.
    * ```json
@@ -64,46 +66,57 @@ export class BoardDiscovery
    * }
    * ```
    */
-  private _state: AvailablePorts = {};
-  get state(): AvailablePorts {
-    return this._state;
+  private _availablePorts: AvailablePorts = {};
+  get availablePorts(): AvailablePorts {
+    return this._availablePorts;
   }
 
   onStart(): void {
     this.start();
-    this.onClientDidRefresh(() => this.start());
+    this.onClientDidRefresh(() => this.restart());
+  }
+
+  private async restart(): Promise<void> {
+    this.logger.info('restarting before stop');
+    await this.stop();
+    this.logger.info('restarting after stop');
+    return this.start();
   }
 
   onStop(): void {
     this.stop();
   }
 
-  stop(): Promise<void> {
+  async stop(restart = false): Promise<void> {
+    this.logger.info('stop');
+    if (this.stopping) {
+      this.logger.info('stop already stopping');
+      return this.stopping.promise;
+    }
+    if (!this.watching) {
+      return;
+    }
+    this.stopping = new Deferred();
     this.logger.info('>>> Stopping boards watcher...');
     return new Promise<void>((resolve, reject) => {
-      const timeout = this.createTimeout(
-        BoardDiscovery.StopWatchTimeout,
-        reject
-      );
+      const timeout = this.createTimeout(10_000, reject);
       const toDispose = new DisposableCollection();
-      toDispose.pushAll([
-        timeout,
-        this.onStreamDidEndEmitter.event(() => {
-          this.logger.info(
-            `<<< Received the end event from the stream. Boards watcher has been successfully stopped.`
-          );
-          this.watching = false;
+      const waitForEvent = (event: Event<unknown>) =>
+        event(() => {
+          this.logger.info('stop received event: either end or cancel');
           toDispose.dispose();
+          this.stopping?.resolve();
+          this.stopping = undefined;
+          this.logger.info('stop stopped');
           resolve();
-        }),
-        this.onStreamDidCancelEmitter.event(() => {
-          this.logger.info(
-            `<<< Received the cancel event from the stream. Boards watcher has been successfully stopped.`
-          );
-          this.watching = false;
-          toDispose.dispose();
-          resolve();
-        }),
+          if (restart) {
+            this.start();
+          }
+        });
+      toDispose.pushAll([
+        timeout,
+        waitForEvent(this.onStreamDidEndEmitter.event),
+        waitForEvent(this.onStreamDidCancelEmitter.event),
       ]);
       this.logger.info('Canceling boards watcher...');
       this.toDisposeOnStopWatch.dispose();
@@ -149,9 +162,14 @@ export class BoardDiscovery
     }
     const stream = client
       .boardListWatch()
-      .on('end', () => this.onStreamDidEndEmitter.fire())
+      .on('end', () => {
+        this.logger.info('received end');
+        this.onStreamDidEndEmitter.fire();
+      })
       .on('error', (error) => {
+        this.logger.info('error received');
         if (ServiceError.isCancel(error)) {
+          this.logger.info('cancel error received!');
           this.onStreamDidCancelEmitter.fire();
         } else {
           this.logger.error(
@@ -165,13 +183,21 @@ export class BoardDiscovery
       stream,
       uuid: v4(),
       dispose: () => {
+        this.logger.info('disposing requesting cancel');
         // Cancelling the stream will kill the discovery `builtin:mdns-discovery process`.
         // The client (this class) will receive a `{"eventType":"quit","error":""}` response from the CLI.
         stream.cancel();
+        this.logger.info('disposing canceled');
         this.wrapper = undefined;
       },
     };
-    this.toDisposeOnStopWatch.pushAll([wrapper]);
+    this.toDisposeOnStopWatch.pushAll([
+      wrapper,
+      Disposable.create(() => {
+        this.watching?.reject(new Error(`Stopping watcher.`));
+        this.watching = undefined;
+      }),
+    ]);
     return wrapper;
   }
 
@@ -188,17 +214,25 @@ export class BoardDiscovery
   }
 
   async start(): Promise<void> {
+    this.logger.info('start');
+    if (this.stopping) {
+      this.logger.info('start is stopping wait');
+      await this.stopping.promise;
+      this.logger.info('start stopped');
+    }
     if (this.watching) {
-      // We want to avoid starting the board list watch process multiple
-      // times to meet unforeseen consequences
-      return;
+      this.logger.info('start already watching');
+      return this.watching.promise;
     }
+    this.watching = new Deferred();
+    this.logger.info('start new deferred');
     const { client, instance } = await this.coreClient;
     const wrapper = await this.createWrapper(client);
     wrapper.stream.on('data', async (resp: BoardListWatchResponse) => {
       this.logger.info('onData', this.toJson(resp));
       if (resp.getEventType() === 'quit') {
-        await this.stop();
+        this.logger.info('quit received');
+        this.stop();
         return;
       }
 
@@ -217,8 +251,8 @@ export class BoardDiscovery
           throw new Error(`Unexpected event type: '${resp.getEventType()}'`);
         }
 
-        const oldState = deepClone(this._state);
-        const newState = deepClone(this._state);
+        const oldState = deepClone(this._availablePorts);
+        const newState = deepClone(this._availablePorts);
 
         const address = (detectedPort as any).getPort().getAddress();
         const protocol = (detectedPort as any).getPort().getProtocol();
@@ -286,18 +320,21 @@ export class BoardDiscovery
           },
         };
 
-        this._state = newState;
+        this._availablePorts = newState;
         this.notificationService.notifyAttachedBoardsDidChange(event);
       }
     });
+    this.logger.info('start request start watch');
     await this.requestStartWatch(
       new BoardListWatchRequest().setInstance(instance),
       wrapper.stream
     );
-    this.watching = true;
+    this.logger.info('start requested start watch');
+    this.watching.resolve();
+    this.logger.info('start resolved watching');
   }
 
-  getAttachedBoards(state: AvailablePorts = this.state): Board[] {
+  getAttachedBoards(state: AvailablePorts = this.availablePorts): Board[] {
     const attachedBoards: Board[] = [];
     for (const portID of Object.keys(state)) {
       const [, boards] = state[portID];
@@ -306,7 +343,7 @@ export class BoardDiscovery
     return attachedBoards;
   }
 
-  getAvailablePorts(state: AvailablePorts = this.state): Port[] {
+  getAvailablePorts(state: AvailablePorts = this.availablePorts): Port[] {
     const availablePorts: Port[] = [];
     for (const portID of Object.keys(state)) {
       const [port] = state[portID];
@@ -315,6 +352,3 @@ export class BoardDiscovery
     return availablePorts;
   }
 }
-export namespace BoardDiscovery {
-  export const StopWatchTimeout = 10_000;
-}

Diff for: arduino-ide-extension/src/node/boards-service-impl.ts

@@ -60,7 +60,7 @@ export class BoardsServiceImpl
   protected readonly boardDiscovery: BoardDiscovery;
 
   async getState(): Promise<AvailablePorts> {
-    return this.boardDiscovery.state;
+    return this.boardDiscovery.availablePorts;
   }
 
   async getAttachedBoards(): Promise<Board[]> {