text: const Joi = require('joi');
  const mongoose = require('mongoose');
  
  const Customer = mongoose.model('Customer', new mongoose.Schema({
      name: {
        type: String,
        required: true,
        minlength: 3,
        maxlength: 50
      },
      isGold: {
        type: Boolean,
        default: false
      },
      phone: {
        type: String,
        required: true,
        minlength: 5,
        maxlength: 50
      }
    }));
  
    function validateCustomer(customer) {
      const schema = {
        name: Joi.string().min(3).max(50).required(),
        phone: Joi.string().min(5).max(50).required(),
        isGold: Joi.boolean()
      };
    
      return Joi.validate(customer, schema);
    }
  
  exports.Customer = Customer;
  exports.validate = validateCustomer;
  
  