Why is req.body undefined in Multer’s diskStorage destination function?

I’m using Multer to handle file uploads in my Express.js application. I’m trying to access the req.body values in the destination function of Multer’s diskStorage option, but it’s returning undefined.how do i pass name from /registerartist to req.body of multer desination

Here’s my code:

import express from 'express';
import {json} from 'express';
import dotenv from 'dotenv';
import {mongoose} from 'mongoose'; 
import UserModel from './src/Models/usermodel.js';
import TrackModel from './src/Models/trackmodel.js';
import cors from 'cors';
import multer from 'multer';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import { dirname } from 'path';
import SingerSchema from './src/Models/singermodel.js';
import Artist from './src/Models/artistmodel.js';


dotenv.config();

const PORT = process.env.PORT;
const app = express();
app.use(json());
app.use(cors())
app.use(express.urlencoded({ extended: true }));



// Define __dirname for path resolution
const __dirname = dirname(fileURLToPath(import.meta.url));

// Multer Storage Configuration
const upload = multer({
    storage: multer.diskStorage({
      destination: (req, file, cb) => {
        const { name } = req.body; 
        const folderPath = `./uploads/artists/${name}`;
        console.log(folderPath)
        if (!fs.existsSync(folderPath)) {
          fs.mkdirSync(folderPath, { recursive: true });
        }
        cb(null, folderPath);
      },
      filename: (req, file, cb) => {
        cb(null, Date.now() + '-' + file.originalname);
      }
    })
  });
//connect to Database

mongoose.connect("mongodb://localhost:27017/Anitify")
.then(()=>{
    console.log("Connected to Mongodb")
})
.catch((err)=>{
    console.log("Error connecting to mongodb",err);
})




app.post('/registerartist', upload.single('image'),  (req, res) => {
    const { name, email, password, genre } = req.body;

  
    console.log("image is",req.file.image.originalname);
   
    console.log("bodyis",req.body.name);
  
   Artist.findOne({email:email})
   .then(result=>{
        if(!result){
            Artist.create(req.body);
        }else{
            console.log("already exists");
        }
   })
   .then(user=>res.json(user))
   .catch((err)=>{
        console.log(err);
        res.json(err)
   })
  });