feat: Added getMessages for Chat

src/chat/Chat.ts

@@ -26,6 +26,7 @@ import {
   ChatStore,
   ClockSkew,
   Constants,
+  Features,
   MsgKey,
   ReplyButtonModel,
   UserPrefs,
@@ -34,10 +35,13 @@ import {
 import {
   addAndSendMsgToChat,
   findChat,
+  msgFindQuery,
+  MsgFindQueryParams,
   randomMessageId,
 } from '../whatsapp/functions';
 import {
   ChatEventTypes,
+  GetMessagesOptions,
   ListMessageOptions,
   MessageButtonsOptions,
   RawMessage,
@@ -77,6 +81,60 @@ export class Chat extends Emittery<ChatEventTypes> {
     return ChatStore.get(wid);
   }
 
+  /**
+   * Fetch messages from a chat
+   *
+   * @example
+   * ```javascript
+   * // Some messages
+   * WPP.chat.getMessages('<number>@c.us', {
+   *   count: 20,
+   * });
+   *
+   * // All messages
+   * WPP.chat.getMessages('<number>@c.us', {
+   *   count: -1,
+   * });
+   *
+   * // 20 messages before specific message
+   * WPP.chat.getMessages('<number>@c.us', {
+   *   count: 20,
+   *   direction: 'before',
+   *   id: '<full message id>'
+   * });
+   * ```
+   *
+   * @return  {RawMessage[]} List of raw messages
+   */
+  getMessages(
+    chatId: string | Wid,
+    options: GetMessagesOptions = {}
+  ): Promise<RawMessage[]> {
+    const chat = assertGetChat(chatId);
+
+    let count = options.count || 20;
+    const direction = options.direction === 'after' ? 'after' : 'before';
+    const id = options.id || chat.lastReceivedKey?.toString();
+
+    let params: MsgFindQueryParams = {
+      remote: chat.id,
+    } as any;
+
+    if (id) {
+      params = MsgKey.fromString(id) as any;
+    }
+
+    // Fix for multidevice
+    if (count === -1 && Features.supportsFeature('MD_BACKEND')) {
+      count = Infinity;
+    }
+
+    params.count = count;
+    params.direction = direction;
+
+    return msgFindQuery(direction, params);
+  }
+
   prepareMessageButtons(
     message: RawMessage,
     options: MessageButtonsOptions

src/chat/types.ts

@@ -21,6 +21,12 @@ export interface ChatEventTypes {
   idle: undefined;
 }
 
+export interface GetMessagesOptions {
+  count?: number;
+  direction?: 'after' | 'before';
+  id?: string;
+}
+
 export interface SendMessageOptions {
   waitForAck?: boolean;
   createChat?: boolean;

src/whatsapp/functions/index.ts

@@ -18,5 +18,6 @@ export * from './addAndSendMsgToChat';
 export * from './findChat';
 export * from './getOrGenerate';
 export * from './isAuthenticated';
+export * from './msgFindQuery';
 export * from './randomId';
 export * from './sendTextMsgToChat';

src/whatsapp/functions/msgFindQuery.ts

@@ -0,0 +1,44 @@
+/*!
+ * Copyright 2021 WPPConnect Team
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Wid } from '..';
+import { exportModule } from '../exportModule';
+import { ModelPropertiesContructor, MsgModel } from '../models';
+
+export interface MsgFindQueryParams {
+  count: number;
+  direction: 'after' | 'before';
+  remote: Wid;
+  fromMe?: boolean;
+  id?: string;
+  participant?: any;
+}
+
+/**
+ * @whatsapp 2.2136.10:2495
+ */
+export declare function msgFindQuery(
+  direction: 'after' | 'before',
+  params: MsgFindQueryParams
+): Promise<ModelPropertiesContructor<MsgModel>[]>;
+
+exportModule(
+  exports,
+  {
+    msgFindQuery: 'msgFindQuery',
+  },
+  (m) => m.msgFindQuery && m.msgFindByIds
+);