fix(core): proper handling for events with no handlers registered

Matii96 · Apr 5, 2023 · 41eff02 · 41eff02
1 parent 5273e9b
commit 41eff02
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Showing 2 changed files with 31 additions and 18 deletions.
diff --git a/packages/core/lib/executor/messages/events/events.executor.impl.spec.ts b/packages/core/lib/executor/messages/events/events.executor.impl.spec.ts
@@ -50,25 +50,23 @@ describe('EventsExecutor', () => {
       );
     });
 
-    it('should handle event', (done) => {
-      executor.execute(subject, event).subscribe({
-        complete() {
-          expect(handler.handle).toHaveBeenCalledTimes(1);
-          done();
-        },
-      });
+    it('should handle event with its handler', async () => {
+      await lastValueFrom(executor.execute(subject, event));
+      expect(handler.handle).toHaveBeenCalledTimes(1);
     });
 
-    it('should emit event handling steps', (done) => {
-      executor.execute(subject, event).subscribe({
-        complete() {
-          expect(eventStates).toEqual([
-            new HandlingStartedEventProcessingState(handler),
-            new HandlingCompletedEventProcessingState(handler),
-          ]);
-          done();
-        },
-      });
+    it('should handle event with no handlers registered', async () => {
+      class NoHandlersEvent {}
+      const event = new NoHandlersEvent();
+      expect(await lastValueFrom(executor.execute(subject, event))).toBe(event);
+    });
+
+    it('should emit event handling steps', async () => {
+      await lastValueFrom(executor.execute(subject, event));
+      expect(eventStates).toEqual([
+        new HandlingStartedEventProcessingState(handler),
+        new HandlingCompletedEventProcessingState(handler),
+      ]);
     });
   });
 

diff --git a/packages/core/lib/executor/messages/events/events.executor.impl.ts b/packages/core/lib/executor/messages/events/events.executor.impl.ts
@@ -1,4 +1,18 @@
-import { catchError, defer, from, last, map, mergeMap, of, retry, Subject, tap, throwError, timeout } from 'rxjs';
+import {
+  catchError,
+  defaultIfEmpty,
+  defer,
+  from,
+  last,
+  map,
+  mergeMap,
+  of,
+  retry,
+  Subject,
+  tap,
+  throwError,
+  timeout,
+} from 'rxjs';
 import { Event } from '../../../messages/event/event';
 import { EventsProvidersSchema } from '../../../providers-manager/messages/events/interfaces/events-providers-schema.interface';
 import { IEventHandler, MessageTypes } from '../../../messages';
@@ -31,6 +45,7 @@ export class MediatorEventsExecutor implements EventsExecutor {
         isPromise(handler) ? from(handler as Promise<IEventHandler<Event>>) : of(handler as IEventHandler<Event>)
       ),
       mergeMap((handler) => this.handleEvent({ config, messageProcessing, event, handler })),
+      defaultIfEmpty(undefined), // There can be no handlers registered for this event
       last(),
       map(() => event)
     );