Fixed message/user endpoint bugs and added clarifying comments

backend/controllers/message.controller.js

@@ -1,29 +1,34 @@
 import Conversation from "../models/conversation.model.js";
 import Message from "../models/message.model.js";
-import { getReceiverSocketId, io } from "../socket/socket.js";
+//import { getReceiverSocketId, io } from "../socket/socket.js";
 
 export const sendMessage = async (req, res) => {
 	try {
+		//req attributes: message, *receiverId, user
 		const { message } = req.body;
-		const { id: receiverId } = req.params;
-		const senderId = req.user._id;
+		const { id: receiverId } = req.params; //assign id at the end of url /send/:id" to receiverId
+		const senderId = req.user._id; //protectRoute.js adds user to req attributes, and ._id is a special field for mognoose models
 
+		//find the specific conversation between the sender and receiver (no groupchats)
 		let conversation = await Conversation.findOne({
 			participants: { $all: [senderId, receiverId] },
 		});
 
+		//if this convo doesn't exist, open up a new DM
 		if (!conversation) {
 			conversation = await Conversation.create({
 				participants: [senderId, receiverId],
 			});
 		}
 
+		//initialize a new message
 		const newMessage = new Message({
 			senderId,
 			receiverId,
 			message,
 		});
 
+		//if new message is successfully created, add the _id to the messages attribute of conversation object
 		if (newMessage) {
 			conversation.messages.push(newMessage._id);
 		}
@@ -33,7 +38,8 @@ export const sendMessage = async (req, res) => {
 		// await conversation.save();
 		// await newMessage.save();
 
-		// this will run in parallel
+		// saves the message to db, access by going to MongoDB website > cluster > chat-app-db > conversations/messages
+		// the Promise.all() allows us to run conversation.save() and newMessage.save() in parallel
 		await Promise.all([conversation.save(), newMessage.save()]);
 
 		res.status(201).json(newMessage);
@@ -45,9 +51,10 @@ export const sendMessage = async (req, res) => {
 
 export const getMessages = async (req, res) => {
     try {
-        const {id:userToChatId} = req.params.id; //get req.params.id and rename to userToChatId
-        const senderId = req.user._id;
+        const {id:userToChatId} = req.params; //get req.params.id and rename to userToChatId
+        const senderId = req.user._id; //get user._id again using protectRoute.js
 
+		console.log(senderId)
         //conversation document, has array of mesage references as an attribute, use mongoose populate method to get actual contents of each message
         const conversation = await Conversation.findOne({
             participants: {$all: [senderId, userToChatId]},

backend/middleware/protectRoute.js

@@ -3,6 +3,7 @@ import User from "../models/user.model.js";
 
 const protectRoute = async (req, res, next) => {
     try {
+        //req params: cookies (has jwt), user (assigned at end)
         const token = req.cookies.jwt;
         //case where there is no token in the request
         if (!token) {
@@ -29,7 +30,7 @@ const protectRoute = async (req, res, next) => {
         //because of this line of code, we can use req.user._id instead of req.user.Id
 		req.user = user;
 
-        //this says that once everything has run, exit this function and call the next one
+        //this says that if everything has successfully ran by this point, exit this function and call the "next" function (passed as a parameter)
 		next();
     } catch (error) {
         console.log("Error in protectRoute middleware: ", error.message);

backend/routes/message.routes.js

@@ -1,11 +1,13 @@
 import express, { Router } from "express";
-import { sendMessage } from "../controllers/message.controller";
-import protectRoute from "../middleware/protectRoute";
+import { getMessages, sendMessage } from "../controllers/message.controller.js";
+import protectRoute from "../middleware/protectRoute.js";
 
 const router = express.Router();
 
 //when we have a post request, we first run protectRoute until the next() call is reached, then we run sendMessage
 //protectRoute makes sure that only authenticated users can send a message
+//access id using req.params.id
+router.get("/:id", protectRoute, getMessages)
 router.post("/send/:id", protectRoute, sendMessage)
 
 export default router;

backend/server.js

@@ -3,8 +3,8 @@ import dotenv from "dotenv";
 import cookieParser from "cookie-parser";
 
 import authRoutes from "./routes/auth.routes.js";
-import messageRoutes from "./routes/auth.routes.js";
-import userRoutes from "./routes/auth.routes.js";
+import messageRoutes from "./routes/message.routes.js";
+import userRoutes from "./routes/user.routes.js";
 
 import connectToMongoDB from "./db/connectToMongoDB.js";