refactor(chat-app): add utility function to emit socket event inside …

…the controllers

src/constants.js

@@ -99,3 +99,5 @@ export const ChatEventEnum = Object.freeze({
   // ? when participant starts typing
   TYPING_EVENT: "typing",
 });
+
+export const AvailableChatEvents = Object.values(ChatEventEnum);

src/controllers/apps/chat-app/chat.controllers.js

@@ -3,6 +3,7 @@ import { ChatEventEnum } from "../../../constants.js";
 import { User } from "../../../models/apps/auth/user.models.js";
 import { Chat } from "../../../models/apps/chat-app/chat.models.js";
 import { ChatMessage } from "../../../models/apps/chat-app/message.models.js";
+import { emitSocketEvent } from "../../../socket/index.js";
 import { ApiError } from "../../../utils/ApiError.js";
 import { ApiResponse } from "../../../utils/ApiResponse.js";
 import { asyncHandler } from "../../../utils/asyncHandler.js";
@@ -197,10 +198,12 @@ const createOrGetAOneOnOneChat = asyncHandler(async (req, res) => {
     if (participant._id.toString() === req.user._id.toString()) return; // don't emit the event for the logged in use as he is the one who is initiating the chat
 
     // emit event to other participants with new chat as a payload
-    req.app
-      .get("io")
-      .in(participant._id.toString())
-      .emit(ChatEventEnum.NEW_CHAT_EVENT, payload);
+    emitSocketEvent(
+      req,
+      participant._id?.toString(),
+      ChatEventEnum.NEW_CHAT_EVENT,
+      payload
+    );
   });
 
   return res
@@ -258,10 +261,12 @@ const createAGroupChat = asyncHandler(async (req, res) => {
   payload?.participants?.forEach((participant) => {
     if (participant._id.toString() === req.user._id.toString()) return; // don't emit the event for the logged in use as he is the one who is initiating the chat
     // emit event to other participants with new chat as a payload
-    req.app
-      .get("io")
-      .in(participant._id.toString())
-      .emit(ChatEventEnum.NEW_CHAT_EVENT, payload);
+    emitSocketEvent(
+      req,
+      participant._id?.toString(),
+      ChatEventEnum.NEW_CHAT_EVENT,
+      payload
+    );
   });
 
   return res
@@ -339,10 +344,12 @@ const renameGroupChat = asyncHandler(async (req, res) => {
   // logic to emit socket event about the updated chat name to the participants
   payload?.participants?.forEach((participant) => {
     // emit event to all the participants with updated chat as a payload
-    req.app
-      .get("io")
-      .in(participant._id.toString())
-      .emit(ChatEventEnum.UPDATE_GROUP_NAME_EVENT, payload);
+    emitSocketEvent(
+      req,
+      participant._id?.toString(),
+      ChatEventEnum.UPDATE_GROUP_NAME_EVENT,
+      payload
+    );
   });
 
   return res
@@ -385,10 +392,12 @@ const deleteGroupChat = asyncHandler(async (req, res) => {
   chat?.participants?.forEach((participant) => {
     if (participant._id.toString() === req.user._id.toString()) return; // don't emit the event for the logged in use as he is the one who is deleting
     // emit event to other participants with left chat as a payload
-    req.app
-      .get("io")
-      .in(participant._id.toString())
-      .emit(ChatEventEnum.LEAVE_CHAT_EVENT, chat);
+    emitSocketEvent(
+      req,
+      participant._id?.toString(),
+      ChatEventEnum.LEAVE_CHAT_EVENT,
+      chat
+    );
   });
 
   return res
@@ -424,10 +433,12 @@ const deleteOneOnOneChat = asyncHandler(async (req, res) => {
   );
 
   // emit event to other participant with left chat as a payload
-  req.app
-    .get("io")
-    .in(otherParticipant?._id.toString())
-    .emit(ChatEventEnum.LEAVE_CHAT_EVENT, payload);
+  emitSocketEvent(
+    req,
+    otherParticipant._id?.toString(),
+    ChatEventEnum.LEAVE_CHAT_EVENT,
+    payload
+  );
 
   return res
     .status(200)
@@ -485,10 +496,7 @@ const addNewParticipantInGroupChat = asyncHandler(async (req, res) => {
   }
 
   // emit new chat event to the added participant
-  req.app
-    .get("io")
-    .in(participantId)
-    .emit(ChatEventEnum.NEW_CHAT_EVENT, payload);
+  emitSocketEvent(req, participantId, ChatEventEnum.NEW_CHAT_EVENT, payload);
 
   return res
     .status(200)
@@ -546,10 +554,7 @@ const removeParticipantFromGroupChat = asyncHandler(async (req, res) => {
   }
 
   // emit leave chat event to the removed participant
-  req.app
-    .get("io")
-    .in(participantId)
-    .emit(ChatEventEnum.LEAVE_CHAT_EVENT, payload);
+  emitSocketEvent(req, participantId, ChatEventEnum.LEAVE_CHAT_EVENT, payload);
 
   return res
     .status(200)

src/controllers/apps/chat-app/message.controllers.js

@@ -2,6 +2,7 @@ import mongoose from "mongoose";
 import { ChatEventEnum } from "../../../constants.js";
 import { Chat } from "../../../models/apps/chat-app/chat.models.js";
 import { ChatMessage } from "../../../models/apps/chat-app/message.models.js";
+import { emitSocketEvent } from "../../../socket/index.js";
 import { ApiError } from "../../../utils/ApiError.js";
 import { ApiResponse } from "../../../utils/ApiResponse.js";
 import { asyncHandler } from "../../../utils/asyncHandler.js";
@@ -136,10 +137,12 @@ const sendMessage = asyncHandler(async (req, res) => {
     if (participantObjectId.toString() === req.user._id.toString()) return;
 
     // emit the receive message event to the other participants with received message as the payload
-    req.app
-      .get("io")
-      .in(participantObjectId.toString())
-      .emit(ChatEventEnum.MESSAGE_RECEIVED_EVENT, receivedMessage);
+    emitSocketEvent(
+      req,
+      participantObjectId.toString(),
+      ChatEventEnum.MESSAGE_RECEIVED_EVENT,
+      receivedMessage
+    );
   });
 
   return res

src/socket/index.js

@@ -1,7 +1,7 @@
 import cookie from "cookie";
 import jwt from "jsonwebtoken";
 import { Server, Socket } from "socket.io";
-import { ChatEventEnum } from "../constants.js";
+import { AvailableChatEvents, ChatEventEnum } from "../constants.js";
 import { User } from "../models/apps/auth/user.models.js";
 import { ApiError } from "../utils/ApiError.js";
 
@@ -100,4 +100,16 @@ const initializeSocketIO = (io) => {
   });
 };
 
-export { initializeSocketIO };
+/**
+ *
+ * @param {import("express").Request} req - Request object to access the `io` instance set at the entry point
+ * @param {string} roomId - Room where the event should be emitted
+ * @param {AvailableChatEvents[0]} event - Event that should be emitted
+ * @param {any} payload - Data that should be sent when emitting the event
+ * @description Utility function responsible to abstract the logic of socket emission via the io instance
+ */
+const emitSocketEvent = (req, roomId, event, payload) => {
+  req.app.get("io").in(roomId).emit(event, payload);
+};
+
+export { initializeSocketIO, emitSocketEvent };