api-client/store/index.js

import Vuex from 'vuex';
import state from './state';
import VuexPersist from 'vuex-persist'

export default {
  install(Vue) {
    Vue.use(Vuex);

    const vuexLocalStorage = new VuexPersist({
      key: 'vuex',
      storage: window.localStorage,
      reducer: ({
        ...request
      }) => ({
        ...request
      })
    })

    const store = new Vuex.Store({
      state,
      plugins: [vuexLocalStorage.plugin]
    });

    Vue.prototype.$store = store;
  },
};