Revert "Support asynchronous action handlers on client-side (#457)" (#459)

This reverts commit 609c2ba.

Author: tortmayr

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

@@ -16,20 +16,17 @@
 import {
     Action,
     ActionDispatcher,
-    ActionHandler,
     ActionHandlerRegistry,
     Deferred,
     EMPTY_ROOT,
     GModelRoot,
     IActionDispatcher,
-    RejectAction,
     RequestAction,
     ResponseAction,
     SetModelAction,
     TYPES
 } from '@eclipse-glsp/sprotty';
 import { inject, injectable } from 'inversify';
-import * as sprotty from 'sprotty-protocol/lib/actions';
 import { GLSPActionHandlerRegistry } from './action-handler-registry';
 import { IGModelRootListener } from './editor-context-service';
 import { OptionalAction } from './model/glsp-model-source';
@@ -128,96 +125,26 @@ export class GLSPActionDispatcher extends ActionDispatcher implements IGModelRoo
         return result;
     }
 
-    protected override async handleAction(action: Action): Promise<void> {
+    protected override handleAction(action: Action): Promise<void> {
         if (ResponseAction.hasValidResponseId(action)) {
-            return this.handleResponseAction(action);
-        }
-        if (OptionalAction.is(action) && !this.hasHandler(action)) {
-            return Promise.resolve();
-        }
-        if (sprotty.UndoAction.KIND === action.kind) {
-            return this.handleUndoAction(action);
-        }
-        if (sprotty.RedoAction.KIND === action.kind) {
-            return this.handleRedoAction(action);
-        }
-        return this.doHandleAction(action);
-    }
-
-    protected handleResponseAction(action: ResponseAction): Promise<void> {
-        // clear any pending timeout
-        const timeout = this.timeouts.get(action.responseId);
-        if (timeout !== undefined) {
-            clearTimeout(timeout);
-            this.timeouts.delete(action.responseId);
-        }
-
-        // check for matching request
-        const request = this.requests.get(action.responseId);
-        if (!request) {
-            // treat no matching request by dispatching action normally
-            this.logger.log(this, 'No matching request for response, dispatch normally', action);
-            action.responseId = '';
-            return this.handleAction(action);
-        }
-
-        this.requests.delete(action.responseId);
-        if (RejectAction.is(action)) {
-            // translation reject action to request rejection
-            request.reject(new Error(action.message));
-            this.logger.warn(this, `Request with id ${action.responseId} failed.`, action.message, action.detail);
-        } else {
-            request.resolve(action);
-        }
-        return Promise.resolve();
-    }
-
-    protected handleUndoAction(action: Action): Promise<void> {
-        return this.commandStack.undo().then(() => {});
-    }
-
-    protected handleRedoAction(action: Action): Promise<void> {
-        return this.commandStack.redo().then(() => {});
-    }
-
-    protected async doHandleAction(action: Action): Promise<void> {
-        const handlers = this.actionHandlerRegistry.get(action.kind);
-        if (handlers.length === 0) {
-            return this.handleActionWithoutHandler(action);
-        } else {
-            return this.handlerActionWithHandler(action, handlers);
-        }
-    }
+            // clear timeout
+            const timeout = this.timeouts.get(action.responseId);
+            if (timeout !== undefined) {
+                clearTimeout(timeout);
+                this.timeouts.delete(action.responseId);
+            }
 
-    protected handleActionWithoutHandler(action: Action): Promise<void> {
-        this.logger.warn(this, 'Missing handler for action', action);
-        const error = new Error(`Missing handler for action '${action.kind}'`);
-        if (RequestAction.is(action)) {
-            const request = this.requests.get(action.requestId);
-            if (request !== undefined) {
-                this.requests.delete(action.requestId);
-                request.reject(error);
+            // Check if we have a pending request for the response.
+            // If not the  we clear the responseId => action will be dispatched normally
+            const deferred = this.requests.get(action.responseId);
+            if (deferred === undefined) {
+                action.responseId = '';
             }
         }
-        return Promise.reject(error);
-    }
-
-    protected async handlerActionWithHandler(action: Action, handlers: ActionHandler[]): Promise<any> {
-        this.logger.log(this, 'Handle', action);
-        const handlerResults: Promise<any>[] = [];
-        for (const handler of handlers) {
-            const handlerResult = Promise.resolve(handler.handle(action)).then<any>(result => {
-                if (Action.is(result)) {
-                    return this.dispatch(result);
-                } else if (result !== undefined) {
-                    this.blockUntil = result.blockUntil;
-                    return this.commandStack.execute(result);
-                }
-                return undefined;
-            });
-            handlerResults.push(handlerResult);
+        if (!this.hasHandler(action) && OptionalAction.is(action)) {
+            return Promise.resolve();
         }
-        return Promise.all(handlerResults) as Promise<any>;
+        return super.handleAction(action);
     }
 
     override request<Res extends ResponseAction>(action: RequestAction<Res>): Promise<Res> {

packages/glsp-sprotty/src/action-handler-override.ts

@@ -22,6 +22,7 @@ import {
     SModelRootImpl as GModelRoot,
     ICommand,
     IActionDispatcher as SIActionDispatcher,
+    IActionHandler as SIActionHandler,
     IButtonHandler as SIButtonHandler,
     ICommandPaletteActionProvider as SICommandPaletteActionProvider,
     ICommandStack as SICommandStack,
@@ -42,6 +43,14 @@ import {
  *
  */
 
+/**
+ * An action handler accepts an action and reacts to it by returning either a command to be
+ * executed, or another action to be dispatched.
+ */
+export interface IActionHandler extends SIActionHandler {
+    handle(action: Action): ICommand | Action | void;
+}
+
 export interface IButtonHandler extends SIButtonHandler {
     buttonPressed(button: GButton): (Action | Promise<Action>)[];
 }

packages/glsp-sprotty/src/api-override.ts

@@ -13,7 +13,6 @@
  *
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  ********************************************************************************/
-export * from './action-handler-override';
 export * from './api-override';
 export * from './feature-modules';
 export * from './layout-override';

packages/glsp-sprotty/src/index.ts

@@ -29,7 +29,13 @@ export * from '@eclipse-glsp/protocol/lib/di';
 // export * from 'sprotty/lib/base/actions/action';
 // Exclude IActionDispatcher and IActionDispatcherProvider. Exported via api-override module instead
 export { ActionDispatcher, PostponedAction } from 'sprotty/lib/base/actions/action-dispatcher';
-// export * from 'sprotty/lib/base/actions/action-handler';
+export {
+    ActionHandlerRegistration,
+    ActionHandlerRegistry,
+    configureActionHandler,
+    IActionHandlerInitializer,
+    onAction
+} from 'sprotty/lib/base/actions/action-handler';
 export * from 'sprotty/lib/base/actions/diagram-locker';
 
 export * from 'sprotty/lib/base/animations/animation';