amazone/server/models/user.js

const mongoose = require('mongoose')
const Schema = mongoose.Schema
const bcrypt = require('bcrypt-nodejs')

const UserSchema = new Schema({
  name: String,
  email: { type: String, unique: true, required: true },
  password: { type: String, required: true },
  address: { type:Schema.Types.ObjectId, ref: 'Address' }
})

UserSchema.pre('save', function(next) {
  let user = this
  if (this.isModified('password') || this.isNew) {
    // bcrypt.hash
    bcrypt.genSalt(10, function(err, salt) {
      if (err) {
        return next(err)
      }

      bcrypt.hash(user.password, salt, null, function (err, hash) {
        if (err) {
          return next (err)
        }
        
        user.password = hash
        next()
      })

    })
  } else {
    return next()
  }
})

UserSchema.methods.comparePassword = function (password, next) {
  let user = this
  return bcrypt.compareSync(password, user.password)
}

module.exports = mongoose.model('User', UserSchema)