refactor: channels design to allow attachment ownership

api/src/attachment/schemas/attachment.schema.ts

@@ -149,13 +149,13 @@ export class Attachment extends AttachmentStub {
 @Schema({ timestamps: true })
 export class UserAttachmentFull extends AttachmentStub {
   @Type(() => User)
-  owner: User | null;
+  owner: User | undefined;
 }
 
 @Schema({ timestamps: true })
 export class SubscriberAttachmentFull extends AttachmentStub {
   @Type(() => Subscriber)
-  owner: Subscriber | null;
+  owner: Subscriber | undefined;
 }
 
 export type AttachmentDocument = THydratedDocument<Attachment>;

api/src/attachment/services/attachment.service.ts

@@ -30,6 +30,7 @@ import { BaseService } from '@/utils/generics/base-service';
 import { AttachmentMetadataDto } from '../dto/attachment.dto';
 import { AttachmentRepository } from '../repositories/attachment.repository';
 import { Attachment } from '../schemas/attachment.schema';
+import { TAttachmentContext } from '../types';
 import {
   fileExists,
   generateUniqueFilename,
@@ -156,6 +157,18 @@ export class AttachmentService extends BaseService<Attachment> {
     }
   }
 
+  /**
+   * Get the attachment root directory given the context
+   *
+   * @param context The attachment context
+   * @returns The root directory path
+   */
+  getRootDirByContext(context: TAttachmentContext) {
+    return context === 'subscriber_avatar' || context === 'user_avatar'
+      ? config.parameters.avatarDir
+      : config.parameters.uploadDir;
+  }
+
   /**
    * Uploads files to the server. If a storage plugin is configured it uploads files accordingly.
    * Otherwise, uploads files to the local directory.
@@ -168,16 +181,12 @@ export class AttachmentService extends BaseService<Attachment> {
   async store(
     file: Buffer | Stream | Readable | Express.Multer.File,
     metadata: AttachmentMetadataDto,
-    rootDir = config.parameters.uploadDir,
   ): Promise<Attachment | undefined> {
     if (this.getStoragePlugin()) {
-      const storedDto = await this.getStoragePlugin()?.store?.(
-        file,
-        metadata,
-        rootDir,
-      );
+      const storedDto = await this.getStoragePlugin()?.store?.(file, metadata);
       return storedDto ? await this.create(storedDto) : undefined;
     } else {
+      const rootDir = this.getRootDirByContext(metadata.context);
       const uniqueFilename = generateUniqueFilename(metadata.name);
       const filePath = resolve(join(rootDir, sanitizeFilename(uniqueFilename)));
 
@@ -225,10 +234,7 @@ export class AttachmentService extends BaseService<Attachment> {
    * @param rootDir - The root directory where attachment shoud be located.
    * @returns A promise that resolves to a StreamableFile representing the downloaded attachment.
    */
-  async download(
-    attachment: Attachment,
-    rootDir = config.parameters.uploadDir,
-  ): Promise<StreamableFile> {
+  async download(attachment: Attachment): Promise<StreamableFile> {
     if (this.getStoragePlugin()) {
       const streamableFile =
         await this.getStoragePlugin()?.download(attachment);
@@ -238,6 +244,7 @@ export class AttachmentService extends BaseService<Attachment> {
 
       return streamableFile;
     } else {
+      const rootDir = this.getRootDirByContext(attachment.context);
       const path = resolve(join(rootDir, attachment.location));
 
       if (!fileExists(path)) {

api/src/attachment/types/index.ts

@@ -6,6 +6,8 @@
  * 2. All derivative works must include clear attribution to the original creator and software, Hexastack and Hexabot, in a prominent location (e.g., in the software's "About" section, documentation, and README file).
  */
 
+import { Readable, Stream } from 'stream';
+
 /**
  * Defines the types of owners for an attachment,
  * indicating whether the file belongs to a User or a Subscriber.
@@ -31,3 +33,25 @@ export enum AttachmentContext {
 }
 
 export type TAttachmentContext = `${AttachmentContext}`;
+
+export class AttachmentFile {
+  /**
+   * File original file name
+   */
+  file: Buffer | Stream | Readable | Express.Multer.File;
+
+  /**
+   * File original file name
+   */
+  name?: string;
+
+  /**
+   * File size in bytes
+   */
+  size: number;
+
+  /**
+   * File MIME type
+   */
+  type: string;
+}

api/src/channel/lib/EventWrapper.ts

@@ -6,6 +6,7 @@
  * 2. All derivative works must include clear attribution to the original creator and software, Hexastack and Hexabot, in a prominent location (e.g., in the software's "About" section, documentation, and README file).
  */
 
+import { Attachment } from '@/attachment/schemas/attachment.schema';
 import { Subscriber } from '@/chat/schemas/subscriber.schema';
 import { AttachmentPayload } from '@/chat/schemas/types/attachment';
 import { SubscriberChannelData } from '@/chat/schemas/types/channel';
@@ -29,19 +30,24 @@ export default abstract class EventWrapper<
     eventType: StdEventType;
     messageType?: IncomingMessageType;
     raw: E;
+    attachments?: Attachment[];
   },
   E,
   N extends ChannelName = ChannelName,
   C extends ChannelHandler = ChannelHandler<N>,
   S = SubscriberChannelDict[N],
 > {
-  _adapter: A = { raw: {}, eventType: StdEventType.unknown } as A;
+  _adapter: A = {
+    raw: {},
+    eventType: StdEventType.unknown,
+    attachments: undefined,
+  } as A;
 
   _handler: C;
 
   channelAttrs: S;
 
-  _profile!: Subscriber;
+  subscriber!: Subscriber;
 
   _nlp!: NLU.ParseEntities;
 
@@ -177,7 +183,7 @@ export default abstract class EventWrapper<
    * @returns event sender data
    */
   getSender(): Subscriber {
-    return this._profile;
+    return this.subscriber;
   }
 
   /**
@@ -186,7 +192,7 @@ export default abstract class EventWrapper<
    * @param profile - Sender data
    */
   setSender(profile: Subscriber) {
-    this._profile = profile;
+    this.subscriber = profile;
   }
 
   /**
@@ -194,9 +200,13 @@ export default abstract class EventWrapper<
    *
    * Child class can perform operations such as storing files as attachments.
    */
-  preprocess() {
-    // Nothing ...
-    return Promise.resolve();
+  async preprocess() {
+    if (
+      this._adapter.eventType === StdEventType.message &&
+      this._adapter.messageType === IncomingMessageType.attachments
+    ) {
+      await this._handler.persistMessageAttachments(this);
+    }
   }
 
   /**

api/src/channel/lib/Handler.ts

@@ -17,12 +17,17 @@ import {
 import { JwtService, JwtSignOptions } from '@nestjs/jwt';
 import { plainToClass } from 'class-transformer';
 import { NextFunction, Request, Response } from 'express';
+import mime from 'mime';
+import { v4 as uuidv4 } from 'uuid';
 
 import { Attachment } from '@/attachment/schemas/attachment.schema';
 import { AttachmentService } from '@/attachment/services/attachment.service';
+import { AttachmentFile } from '@/attachment/types';
 import { SubscriberCreateDto } from '@/chat/dto/subscriber.dto';
 import { AttachmentRef } from '@/chat/schemas/types/attachment';
 import {
+  IncomingMessageType,
+  StdEventType,
   StdOutgoingEnvelope,
   StdOutgoingMessage,
 } from '@/chat/schemas/types/message';
@@ -50,7 +55,7 @@ export default abstract class ChannelHandler<
   private readonly settings: ChannelSetting<N>[];
 
   @Inject(AttachmentService)
-  protected readonly attachmentService: AttachmentService;
+  public readonly attachmentService: AttachmentService;
 
   @Inject(JwtService)
   protected readonly jwtService: JwtService;
@@ -206,15 +211,62 @@ export default abstract class ChannelHandler<
   ): Promise<{ mid: string }>;
 
   /**
-   * Fetch the end user profile data
+   * Calls the channel handler to fetch attachments and stores them
+   *
+   * @param event
+   * @returns An attachment array
+   */
+  getMessageAttachments?(
+    event: EventWrapper<any, any, N>,
+  ): Promise<AttachmentFile[]>;
+
+  /**
+   * Fetch the subscriber profile data
    * @param event - The message event received
    * @returns {Promise<Subscriber>} - The channel's response, otherwise an error
-   
    */
-  abstract getUserData(
+  getSubscriberAvatar?(
+    event: EventWrapper<any, any, N>,
+  ): Promise<AttachmentFile | undefined>;
+
+  /**
+   * Fetch the subscriber profile data
+   *
+   * @param event - The message event received
+   * @returns {Promise<Subscriber>} - The channel's response, otherwise an error
+   */
+  abstract getSubscriberData(
     event: EventWrapper<any, any, N>,
   ): Promise<SubscriberCreateDto>;
 
+  /**
+   * Persist Message attachments
+   *
+   * @returns Resolves the promise once attachments are fetched and stored
+   */
+  async persistMessageAttachments(event: EventWrapper<any, any, N>) {
+    if (
+      event._adapter.eventType === StdEventType.message &&
+      event._adapter.messageType === IncomingMessageType.attachments &&
+      this.getMessageAttachments
+    ) {
+      const metadatas = await this.getMessageAttachments(event);
+      const subscriber = event.getSender();
+      event._adapter.attachments = await Promise.all(
+        metadatas.map(({ file, name, type, size }) => {
+          return this.attachmentService.store(file, {
+            name: `${name ? `${name}-` : ''}${uuidv4()}.${mime.extension(type)}`,
+            type,
+            size,
+            context: 'message_attachment',
+            ownerType: 'Subscriber',
+            owner: subscriber.id,
+          });
+        }),
+      );
+    }
+  }
+
   /**
    * Custom channel middleware
    * @param req

api/src/chat/controllers/subscriber.controller.ts

@@ -20,7 +20,6 @@ import {
 import { CsrfCheck } from '@tekuconcept/nestjs-csrf';
 
 import { AttachmentService } from '@/attachment/services/attachment.service';
-import { config } from '@/config';
 import { CsrfInterceptor } from '@/interceptors/csrf.interceptor';
 import { LoggerService } from '@/logger/logger.service';
 import { BaseController } from '@/utils/generics/base-controller';
@@ -159,10 +158,7 @@ export class SubscriberController extends BaseController<
         throw new Error('User has no avatar');
       }
 
-      return await this.attachmentService.download(
-        subscriber.avatar,
-        config.parameters.avatarDir,
-      );
+      return await this.attachmentService.download(subscriber.avatar);
     } catch (err) {
       this.logger.verbose(
         'Subscriber has no avatar, generating initials avatar ...',

api/src/chat/services/chat.service.ts

@@ -8,7 +8,10 @@
 
 import { Injectable } from '@nestjs/common';
 import { EventEmitter2, OnEvent } from '@nestjs/event-emitter';
+import mime from 'mime';
+import { v4 as uuidv4 } from 'uuid';
 
+import { AttachmentService } from '@/attachment/services/attachment.service';
 import EventWrapper from '@/channel/lib/EventWrapper';
 import { config } from '@/config';
 import { HelperService } from '@/helper/helper.service';
@@ -36,6 +39,7 @@ export class ChatService {
     private readonly botService: BotService,
     private readonly websocketGateway: WebsocketGateway,
     private readonly helperService: HelperService,
+    private readonly attachmentService: AttachmentService,
   ) {}
 
   /**
@@ -248,7 +252,7 @@ export class ChatService {
       });
 
       if (!subscriber) {
-        const subscriberData = await handler.getUserData(event);
+        const subscriberData = await handler.getSubscriberData(event);
         this.eventEmitter.emit('hook:stats:entry', 'new_users', 'New users');
         subscriberData.channel = event.getChannelData();
         subscriber = await this.subscriberService.create(subscriberData);
@@ -260,9 +264,47 @@ export class ChatService {
 
       this.websocketGateway.broadcastSubscriberUpdate(subscriber);
 
+      // Retrieve and store the subscriber avatar
+      if (handler.getSubscriberAvatar) {
+        try {
+          const metadata = await handler.getSubscriberAvatar(event);
+          if (metadata) {
+            const { file, type, size } = metadata;
+            const extension = mime.extension(type);
+
+            const avatar = await this.attachmentService.store(file, {
+              name: `avatar-${uuidv4()}.${extension}`,
+              size,
+              type,
+              context: 'subscriber_avatar',
+              ownerType: 'Subscriber',
+              owner: subscriber.id,
+            });
+
+            if (avatar) {
+              subscriber = await this.subscriberService.updateOne(
+                subscriber.id,
+                {
+                  avatar: avatar.id,
+                },
+              );
+            }
+          }
+        } catch (err) {
+          this.logger.error(
+            `Unable to retrieve avatar for subscriber ${subscriber.id}`,
+            err,
+          );
+        }
+      }
+
+      // Set the subscriber object
       event.setSender(subscriber);
 
-      await event.preprocess();
+      // Preprocess the event (persist attachments, ...)
+      if (event.preprocess) {
+        await event.preprocess();
+      }
 
       // Trigger message received event
       this.eventEmitter.emit('hook:chatbot:received', event);

api/src/extensions/channels/web/base-web-channel.ts

@@ -70,7 +70,7 @@ export default abstract class BaseWebChannelHandler<
     protected readonly eventEmitter: EventEmitter2,
     protected readonly i18n: I18nService,
     protected readonly subscriberService: SubscriberService,
-    protected readonly attachmentService: AttachmentService,
+    public readonly attachmentService: AttachmentService,
     protected readonly messageService: MessageService,
     protected readonly menuService: MenuService,
     protected readonly websocketGateway: WebsocketGateway,
@@ -1321,7 +1321,9 @@ export default abstract class BaseWebChannelHandler<
    *
    * @returns The web's response, otherwise an error
    */
-  async getUserData(event: WebEventWrapper<N>): Promise<SubscriberCreateDto> {
+  async getSubscriberData(
+    event: WebEventWrapper<N>,
+  ): Promise<SubscriberCreateDto> {
     const sender = event.getSender();
     const {
       id: _id,

api/src/plugins/base-storage-plugin.ts

@@ -37,10 +37,7 @@ export abstract class BaseStoragePlugin extends BasePlugin {
   /** @deprecated use store() instead */
   uploadAvatar?(file: Express.Multer.File): Promise<any>;
 
-  abstract download(
-    attachment: Attachment,
-    rootLocation?: string,
-  ): Promise<StreamableFile>;
+  abstract download(attachment: Attachment): Promise<StreamableFile>;
 
   /** @deprecated use download() instead */
   downloadProfilePic?(name: string): Promise<StreamableFile>;
@@ -52,6 +49,5 @@ export abstract class BaseStoragePlugin extends BasePlugin {
   store?(
     file: Buffer | Stream | Readable | Express.Multer.File,
     metadata: AttachmentMetadataDto,
-    rootDir?: string,
   ): Promise<Attachment>;
 }

api/src/user/controllers/user.controller.ts

@@ -110,10 +110,7 @@ export class ReadOnlyUserController extends BaseController<
         throw new Error('User has no avatar');
       }
 
-      return await this.attachmentService.download(
-        user.avatar,
-        config.parameters.avatarDir,
-      );
+      return await this.attachmentService.download(user.avatar);
     } catch (err) {
       this.logger.verbose(
         'User has no avatar, generating initials avatar ...',
@@ -293,18 +290,14 @@ export class ReadWriteUserController extends ReadOnlyUserController {
 
     // Upload Avatar if provided
     const avatar = avatarFile
-      ? await this.attachmentService.store(
-          avatarFile,
-          {
-            name: avatarFile.originalname,
-            size: avatarFile.size,
-            type: avatarFile.mimetype,
-            context: 'user_avatar',
-            ownerType: 'User',
-            owner: req.user.id,
-          },
-          config.parameters.avatarDir,
-        )
+      ? await this.attachmentService.store(avatarFile, {
+          name: avatarFile.originalname,
+          size: avatarFile.size,
+          type: avatarFile.mimetype,
+          context: 'user_avatar',
+          ownerType: 'User',
+          owner: req.user.id,
+        })
       : undefined;
 
     const result = await this.userService.updateOne(

api/src/utils/types/misc.ts

@@ -0,0 +1,9 @@
+/*
+ * Copyright © 2025 Hexastack. All rights reserved.
+ *
+ * Licensed under the GNU Affero General Public License v3.0 (AGPLv3) with the following additional terms:
+ * 1. The name "Hexabot" is a trademark of Hexastack. You may not use this name in derivative works without express written permission.
+ * 2. All derivative works must include clear attribution to the original creator and software, Hexastack and Hexabot, in a prominent location (e.g., in the software's "About" section, documentation, and README file).
+ */
+
+export type PartialExcept<T, K extends keyof T> = Partial<T> & Pick<T, K>;