Allow optional actions to avoid console errors (eclipse-glsp#310)

packages/client/src/base/action-dispatcher.ts

@@ -13,8 +13,9 @@
  *
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  ********************************************************************************/
-import { inject, injectable } from 'inversify';
 import { Action, ActionDispatcher, RequestAction, ResponseAction } from '@eclipse-glsp/sprotty';
+import { inject, injectable } from 'inversify';
+import { OptionalAction } from './model/glsp-model-source';
 import { ModelInitializationConstraint } from './model/model-initialization-constraint';
 
 @injectable()
@@ -76,6 +77,9 @@ export class GLSPActionDispatcher extends ActionDispatcher {
                 action.responseId = '';
             }
         }
+        if (!this.hasHandler(action) && OptionalAction.is(action)) {
+            return Promise.resolve();
+        }
         return super.handleAction(action);
     }
 

packages/client/src/base/model/glsp-model-source.ts

@@ -14,7 +14,6 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  ********************************************************************************/
 
-import { inject, injectable, preDestroy } from 'inversify';
 import {
     Action,
     ActionMessage,
@@ -29,8 +28,10 @@ import {
     ModelSource,
     TYPES
 } from '@eclipse-glsp/sprotty';
+import { inject, injectable, preDestroy } from 'inversify';
 import { GLSPActionHandlerRegistry } from '../action-handler-registry';
 import { IDiagramOptions } from './diagram-loader';
+
 /**
  * A helper interface that allows the client to mark actions that have been received from the server.
  */
@@ -44,14 +45,37 @@ export namespace ServerAction {
     }
 
     /**
-     * Mark the given action as {@link ServerAction} by attaching the "_receivedFromServer" property
+     * Mark the given action as {@link ServerAction} by attaching the "__receivedFromServer" property
      * @param action The action that should be marked as server action
      */
     export function mark(action: Action): void {
         (action as ServerAction).__receivedFromServer = true;
     }
 }
 
+/**
+ * A helper interface that allows the client to mark actions that can be considered optional and should not throw an error if
+ * no handler is available.
+ */
+export interface OptionalAction extends Action {
+    __skipErrorIfNoHandler: true;
+}
+
+export namespace OptionalAction {
+    export function is(object: unknown): object is ServerAction {
+        return Action.is(object) && '__skipErrorIfNoHandler' in object && object.__skipErrorIfNoHandler === true;
+    }
+
+    /**
+     * Mark the given action as {@link OptionalAction} by attaching the "__skipErrorIfNoHandler" property
+     * @param action The action that should be marked as optional action
+     */
+    export function mark<T extends Action>(action: T): T & OptionalAction {
+        (action as unknown as OptionalAction).__skipErrorIfNoHandler = true;
+        return action as T & OptionalAction;
+    }
+}
+
 /**
  * Central component for enabling the client-server action flow with the help of an underlying {@link GLSPClient}.
  * Handles & forwards actions that are intended for the GLSP server. In addition, it handles {@link ActionMessage}s received

packages/client/src/features/tools/change-bounds/change-bounds-tool-feedback.ts

@@ -36,6 +36,7 @@ import { DebouncedFunc, debounce } from 'lodash';
 import { DragAwareMouseListener } from '../../../base/drag-aware-mouse-listener';
 import { CursorCSS, cursorFeedbackAction } from '../../../base/feedback/css-feedback';
 import { FeedbackCommand } from '../../../base/feedback/feedback-command';
+import { OptionalAction } from '../../../base/model/glsp-model-source';
 import { forEachElement } from '../../../utils/gmodel-util';
 import { SResizeHandle, addResizeHandles, isResizable, removeResizeHandles } from '../../change-bounds/model';
 import { createMovementRestrictionFeedback, removeMovementRestrictionFeedback } from '../../change-bounds/movement-restrictor';
@@ -125,7 +126,7 @@ export namespace MoveInitializedEventAction {
     }
 
     export function create(): MoveInitializedEventAction {
-        return { kind: KIND };
+        return OptionalAction.mark({ kind: KIND });
     }
 }
 
@@ -141,7 +142,7 @@ export namespace MoveFinishedEventAction {
     }
 
     export function create(): MoveFinishedEventAction {
-        return { kind: KIND };
+        return OptionalAction.mark({ kind: KIND });
     }
 }
 
@@ -157,6 +158,7 @@ export class FeedbackMoveMouseListener extends DragAwareMouseListener implements
     protected positionUpdater;
     protected elementId2startPos = new Map<string, Point>();
     protected pendingMoveInitialized?: DebouncedFunc<() => void>;
+    protected moveInitialized = false;
 
     constructor(protected tool: ChangeBoundsTool) {
         super();
@@ -178,10 +180,12 @@ export class FeedbackMoveMouseListener extends DragAwareMouseListener implements
     }
 
     protected scheduleMoveInitialized(): void {
+        this.moveInitialized = false;
         this.pendingMoveInitialized?.cancel();
         this.pendingMoveInitialized = debounce(() => {
             this.tool.registerFeedback([MoveInitializedEventAction.create()], this);
             this.pendingMoveInitialized = undefined;
+            this.moveInitialized = true;
         }, 750);
         this.pendingMoveInitialized();
     }
@@ -329,11 +333,12 @@ export class FeedbackMoveMouseListener extends DragAwareMouseListener implements
                 const moveAction = MoveAction.create(elementMoves, { animate: false, finished: true });
                 this.tool.deregisterFeedback(this, [moveAction]);
             }
-        } else if (resetFeedback) {
+        } else if (resetFeedback && this.moveInitialized) {
             this.tool.deregisterFeedback(this, [MoveFinishedEventAction.create()]);
         }
         this.positionUpdater.resetPosition();
         this._isMouseDrag = false;
+        this.moveInitialized = false;
         this.rootElement = undefined;
         this.elementId2startPos.clear();
     }