ajinkya-mhetre-mern/backend/src/controllers/adminController.js

A MERN starter with frontend and backend folders

// ===== src/controllers/adminController.js =====
const User = require('../models/User');
const Product = require('../models/Product');
const Order = require('../models/Order');

const getPendingFarmers = async (req, res) => {
  try {
    const farmers = await User.find({ 
      role: 'farmer', 
      isVerified: false 
    }).select('-password');

    res.json({
      success: true,
      farmers
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

const verifyFarmer = async (req, res) => {
  try {
    const { farmerId } = req.params;
    const { action } = req.body; // 'approve' or 'reject'

    const farmer = await User.findById(farmerId);
    if (!farmer || farmer.role !== 'farmer') {
      return res.status(404).json({ message: 'Farmer not found' });
    }

    if (action === 'approve') {
      farmer.isVerified = true;
      await farmer.save();
      
      res.json({
        success: true,
        message: 'Farmer verified successfully'
      });
    } else if (action === 'reject') {
      await User.findByIdAndDelete(farmerId);
      
      res.json({
        success: true,
        message: 'Farmer application rejected'
      });
    } else {
      res.status(400).json({ message: 'Invalid action' });
    }
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

const getDashboardStats = async (req, res) => {
  try {
    const totalUsers = await User.countDocuments();
    const totalFarmers = await User.countDocuments({ role: 'farmer', isVerified: true });
    const totalCustomers = await User.countDocuments({ role: 'customer' });
    const pendingFarmers = await User.countDocuments({ role: 'farmer', isVerified: false });
    const totalProducts = await Product.countDocuments();
    const totalOrders = await Order.countDocuments();

    res.json({
      success: true,
      stats: {
        totalUsers,
        totalFarmers,
        totalCustomers,
        pendingFarmers,
        totalProducts,
        totalOrders
      }
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

const getAllUsers = async (req, res) => {
  try {
    const users = await User.find().select('-password');
    res.json({
      success: true,
      users
    });
  } catch (error) {
    res.status(500).json({ message: error.message });
  }
};

module.exports = {
  getPendingFarmers,
  verifyFarmer,
  getDashboardStats,
  getAllUsers
};