Event-bus ( WIP )

src/domain/event-bus/events/noteAddedEvent.ts

@@ -0,0 +1,22 @@
+/**
+ * Event that is emitted when a note is added.
+ */
+export const NOTE_ADDED_EVENT_NAME = 'noteAdded';
+
+
+/**
+ *  Note added event
+ */
+export class NoteAddedEvent extends CustomEvent<{ noteId: number; userId: number }> {
+  /**
+   *  Note added event constructor
+   * @param noteId - note internal id
+   * @param userId - user id
+   */
+  constructor(noteId: number, userId: number) {
+    super(NOTE_ADDED_EVENT_NAME, {
+      detail: { noteId,
+        userId },
+    });
+  }
+}

src/domain/event-bus/events/noteVisitedEvent.ts

@@ -0,0 +1,18 @@
+// domain/event-bus/events/noteVisitedEvent.ts
+
+export const NOTE_VISITED_EVENT_NAME = 'noteVisited';
+
+/**
+ *  Note visited event
+ */
+export class NoteVisitedEvent extends CustomEvent<{ noteId: number; userId: number }> {
+  /**
+   *  Note visited event constructor
+   * @param noteId - note internal id
+   * @param userId - user id
+   */
+  constructor(noteId: number, userId: number) {
+    super(NOTE_VISITED_EVENT_NAME, { detail: { noteId,
+      userId } });
+  }
+}

src/domain/event-bus/index.ts

@@ -0,0 +1,43 @@
+import type { NOTE_ADDED_EVENT_NAME, NoteAddedEvent } from './events/noteAddedEvent.js';
+
+/**
+ * Event Bus provides a loosely coupled communication way between Domain and some other layers
+ *
+ * Extends native event emitter called EventTarget
+ */
+export default class EventBus extends EventTarget {
+  private static instance: EventBus;
+
+  /**
+   * EventBus constructor
+   */
+  constructor() {
+    super();
+  }
+
+  /**
+   * Gets the singleton instance of the EventBus
+   */
+  public static getInstance(): EventBus {
+    if (EventBus.instance === undefined) {
+      EventBus.instance = new EventBus();
+    }
+
+    return EventBus.instance;
+  }
+
+  /**
+   * Dispatches an event
+   *
+   * @param event - The event to dispatch
+   */
+  public dispatch(event: Event): boolean {
+    return this.dispatchEvent(event);
+  }
+}
+
+export type CrossDomainEventMap = {
+  [NOTE_ADDED_EVENT_NAME]: NoteAddedEvent,
+};
+
+

src/domain/service/note.ts

@@ -6,6 +6,8 @@ import { DomainError } from '@domain/entities/DomainError.js';
 import type NoteRelationsRepository from '@repository/noteRelations.repository.js';
 import type User from '@domain/entities/user.js';
 import type { NoteList } from '@domain/entities/noteList.js';
+import EventBus from '@domain/event-bus/index.js';
+import { NoteAddedEvent } from '@domain/event-bus/events/noteAddedEvent.js';
 
 /**
  * Note service
@@ -69,6 +71,10 @@ export default class NoteService {
 
       await this.noteRelationsRepository.addNoteRelation(note.id, parentNote.id);
     }
+    /**
+     * Dispatches an event when a note is added
+     */
+    EventBus.getInstance().dispatch(new NoteAddedEvent(note.id, creatorId));
 
     return note;
   }

src/domain/service/noteSettings.ts

@@ -9,6 +9,8 @@ import type User from '@domain/entities/user.js';
 import { createInvitationHash } from '@infrastructure/utils/invitationHash.js';
 import { DomainError } from '@domain/entities/DomainError.js';
 import type { SharedDomainMethods } from './shared/index.js';
+import EventBus from '@domain/event-bus/index.js';
+import { NOTE_ADDED_EVENT_NAME } from '@domain/event-bus/events/noteAddedEvent.js';
 
 /**
  * Service responsible for Note Settings
@@ -31,6 +33,24 @@ export default class NoteSettingsService {
   constructor(noteSettingsRepository: NoteSettingsRepository, teamRepository: TeamRepository, private readonly shared: SharedDomainMethods) {
     this.noteSettingsRepository = noteSettingsRepository;
     this.teamRepository = teamRepository;
+
+    /**
+     * Listen to the note related events
+     */
+    EventBus.getInstance().addEventListener(NOTE_ADDED_EVENT_NAME, async (event) => {
+      const { noteId, userId } = (event as CustomEvent<{ noteId: number; userId: number }>).detail;
+
+      try {
+        await this.addNoteSettings(noteId);
+        await this.createTeamMember({
+          noteId: noteId,
+          userId: userId,
+          role: MemberRole.Write,
+        });
+      } catch (error) {
+        throw error;
+      }
+    });
   }
 
   /**

src/domain/service/noteVisits.ts

@@ -2,6 +2,9 @@ import type { NoteInternalId } from '@domain/entities/note.js';
 import type User from '@domain/entities/user.js';
 import type NoteVisit from '@domain/entities/noteVisit.js';
 import type NoteVisitsRepository from '@repository/noteVisits.repository.js';
+import EventBus from '@domain/event-bus/index.js';
+import { NOTE_ADDED_EVENT_NAME } from '@domain/event-bus/events/noteAddedEvent.js';
+import { NOTE_VISITED_EVENT_NAME } from '@domain/event-bus/events/noteVisitedEvent.js';
 
 /**
  * Note Visits service, which will store latest note visit
@@ -20,6 +23,29 @@ export default class NoteVisitsService {
    */
   constructor(noteVisitRepository: NoteVisitsRepository) {
     this.noteVisitsRepository = noteVisitRepository;
+
+    /**
+     * Listen to the note related events
+     */
+    EventBus.getInstance().addEventListener(NOTE_ADDED_EVENT_NAME, async (event) => {
+      const { noteId, userId } = (event as CustomEvent<{ noteId: number; userId: number }>).detail;
+
+      try {
+        return await this.noteVisitsRepository.saveVisit(noteId, userId);
+      } catch (error) {
+        throw error;
+      }
+    });
+
+    EventBus.getInstance().addEventListener(NOTE_VISITED_EVENT_NAME, async (event) => {
+      const { noteId, userId } = (event as CustomEvent<{ noteId: number; userId: number }>).detail;
+
+      try {
+        await this.noteVisitsRepository.saveVisit(noteId, userId);
+      } catch (error) {
+        console.error('Error saving note visit', error);
+      }
+    });
   }
 
   /**
@@ -40,4 +66,4 @@ export default class NoteVisitsService {
   public async deleteNoteVisits(noteId: NoteInternalId): Promise<boolean> {
     return await this.noteVisitsRepository.deleteNoteVisits(noteId);
   }
-}
+}

src/presentation/http/router/note.ts

@@ -9,6 +9,8 @@ import useMemberRoleResolver from '../middlewares/noteSettings/useMemberRoleReso
 import { MemberRole } from '@domain/entities/team.js';
 import { type NotePublic, definePublicNote } from '@domain/entities/notePublic.js';
 import type NoteVisitsService from '@domain/service/noteVisits.js';
+import EventBus from '@domain/event-bus/index.js';
+import { NoteVisitedEvent } from '@domain/event-bus/events/noteVisitedEvent.js';
 
 /**
  * Interface for the note router.
@@ -43,7 +45,6 @@ const NoteRouter: FastifyPluginCallback<NoteRouterOptions> = (fastify, opts, don
    */
   const noteService = opts.noteService;
   const noteSettingsService = opts.noteSettingsService;
-  const noteVisitsService = opts.noteVisitsService;
 
   /**
    * Prepare note id resolver middleware
@@ -135,7 +136,7 @@ const NoteRouter: FastifyPluginCallback<NoteRouterOptions> = (fastify, opts, don
      * @todo use event bus to save note visits
      */
     if (userId !== null) {
-      await noteVisitsService.saveVisit(noteId, userId);
+      EventBus.getInstance().dispatch(new NoteVisitedEvent(noteId, userId));
     }
 
     const parentId = await noteService.getParentNoteIdByNoteId(note.id);
@@ -224,28 +225,6 @@ const NoteRouter: FastifyPluginCallback<NoteRouterOptions> = (fastify, opts, don
 
     const addedNote = await noteService.addNote(content as JSON, userId as number, parentId); // "authRequired" policy ensures that userId is not null
 
-    /**
-     * Save note visit when note created
-     *
-     * @todo use even bus to save noteVisit
-     */
-
-    await noteVisitsService.saveVisit(addedNote.id, userId!);
-
-    /**
-     * @todo use event bus: emit 'note-added' event and subscribe to it in other modules like 'note-settings'
-     */
-    await noteSettingsService.addNoteSettings(addedNote.id);
-
-    /**
-     * Creates TeamMember with write priveleges
-     */
-    await noteSettingsService.createTeamMember({
-      noteId: addedNote.id,
-      userId: userId as number,
-      role: MemberRole.Write,
-    });
-
     return reply.send({
       id: addedNote.publicId,
     });
@@ -391,15 +370,11 @@ const NoteRouter: FastifyPluginCallback<NoteRouterOptions> = (fastify, opts, don
     ],
   }, async (request, reply) => {
     const noteId = request.note?.id as number;
+    const userId = request.note?.creatorId as number;
 
     const isDeleted = await noteService.unlinkParent(noteId);
 
-    /**
-     * Delete all visits of the note
-     *
-     * @todo use event bus to delete note visits
-     */
-    await noteVisitsService.deleteNoteVisits(noteId);
+    EventBus.getInstance().dispatch(new NoteVisitedEvent(noteId, userId));
 
     /**
      * Check if parent relation was successfully deleted
@@ -464,10 +439,9 @@ const NoteRouter: FastifyPluginCallback<NoteRouterOptions> = (fastify, opts, don
     /**
      * Save note visit if user is authorized
      *
-     * @todo use event bus to save note visits
      */
     if (userId !== null) {
-      await noteVisitsService.saveVisit(note.id, userId);
+      EventBus.getInstance().dispatch(new NoteVisitedEvent(note.id, userId));
     }
 
     /**