const cookie = new Vue({
  computed: {
    content: {
      get () {
        const ret = {}
        const cookieList = document.cookie.split('; ')
        for (const data of cookieList) {
          const [key, value] = data.split('=')
          ret[key] = value
        }
        return ret
      },
      set (obj) {
        for (const key in obj) {
          document.cookie = `${key}=${obj[key].toString()}`
        }
      }
    }
  }
})

cookie.content = {a:1, b:2}
console.log(cookie.content)