Mongodb – How to make relationship between two model in Express & mongoose

The "tasks" field in the response is consistently empty, even though I know there are tasks associated with the user in the database.

I’ve checked my database records, and there are tasks assigned to the user in question, so the issue seems to be with how the data is being fetched or formatted in the API response.

I’ve double-checked my Mongoose models and ensured that the relationship between users and tasks is correctly defined and every response return tasks empty.

Auth midlleware

const verify = async (req, res, next) => {
  const authHeader = req.headers.authorization;

  if (authHeader) {
    const token = authHeader.split(" ")[1];
    try {
      const decoded = await jwt.verify(token, process.env.JWT_ACCESS_KEY);
      req.user = decoded;
      next();
    } catch (err) {
      res.status(401).json({ message: err });
    }
  } else {
    res.status(403).json({ message: "Unauthorized" });
  }
};

GetAll controller tasks if user authorized:

const getAll = async (req , res) => {
  const userId = req.user.payload._id;
  if (userId) {
    try {
      const tasks = await userModel.findById(userId).populate("tasks");
      res.status(200).json({msg: "", data: tasks});
      console.log( req.user.payload.tasks);
      console.log( userId);
    } catch (err) {
      console.log(err);
    }
  } else {
    console.log(err);
  }
}

User schema:

const mongoose = require("mongoose");
const Schema =  mongoose.Schema;


const UserSchema = new Schema({
  name: {
    type: String,
  },
  email: {
    type: String,
    unique: true
  },
  password: {
    type: String,
  },
  tasks: [{ 
    type: mongoose.Schema.Types.ObjectId, 
    ref: 'Task'
  }],
}) 

module.exports = mongoose.model("User", UserSchema);

Task schema:

const mongoose = require("mongoose");
const Schema = mongoose.Schema;

const TaskSchema = new Schema({
  title: {
    type: String,
  },
  status: {
    type: Boolean,
    default: false,
  },
  date: {
    type: String,
    default: new Date().toLocaleDateString().toString(),
  },
  owner: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
});

module.exports = mongoose.model("Task", TaskSchema);

Task in database

I tried every response return tasks field empty, As far as I understand relation between models in a good way.