plugin para uso fácil de Firebase em app Vue

firebase-plugin.js

import Vue from 'vue'
import firebase from 'firebase/app'
import 'firebase/auth'
import 'firebase/firestore'
import router from '@/router'
import store from '@/store'

if (!process.env.FIREBASE_CONFIG) {
  throw new Error('firebase config not found in env')
}

// const { router, store } = Vue.prototype

const config = JSON.parse(process.env.FIREBASE_CONFIG)

firebase.initializeApp(config)

const auth = firebase.auth()
const database = firebase.firestore()

Vue.prototype.$auth = auth
Vue.prototype.$database = database

auth.onAuthStateChanged(async user => {
  if (user !== store.state.auth.user) {
    await store.dispatch('auth/update', { user: user })
  }
  if (user !== null && router.currentRoute.name === 'login') {
    const db = firebase.firestore()
    const userDocumentRef = db.collection('users').doc(user.uid)
    const userDocumentSnapshot = await userDocumentRef.get()
      .catch(err => {
        console.error('error:', err)
        return null
      })
    if (userDocumentSnapshot && userDocumentSnapshot.exists) {
      const userDocument = userDocumentSnapshot.data()
      const { id: roleRawUid = process.env.FALLBACK_ROLE_UID } = userDocument.role
      const roleUid = roleRawUid.replace(/\n\s+/g, '').trim()
      const roleSnapshot = await db.collection('roles').doc(roleUid).get()
        .catch(err => {
          alert('Não foi possível obter papel do usuário:' + err.message)
          auth.signOut()
          throw err
        })
      const role = { ...roleSnapshot.data(), id: roleSnapshot.id };
      store.dispatch('auth/setRole', { role })
    } else {
      const defaultRoleUid = process.env.FALLBACK_ROLE_UID
      const roleUid = defaultRoleUid.replace(/\n\s+/g, '').trim()
      const roleDocumentRef = db.collection('roles').doc(roleUid)
      const roleDocumentSnapshot = await roleDocumentRef.get()
        .catch(err => {
          alert('Não foi possível obter papel do usuário:' + err.message)
          auth.signOut()
          throw err
        })
      const role = roleDocumentSnapshot.data()
      store.dispatch('auth/setRole', { role })
    }
    const { redirect = { name: 'Dashboard' } } = router.currentRoute.query
    router.push(redirect)
  } else if (user === null && router.currentRoute.name !== 'login') {
    router.push({ name: 'login' })
  }
})

auth.onIdTokenChanged(user => {
  if (user !== null) {
    if (!auth.currentUser) {
      return
    }
    auth.currentUser.getIdToken(true)
      .then(token => {
        store.dispatch('auth/token', { token })
      })
      .catch(err => {
        console.error('error while updating token:', err)
        store.dispatch('auth/token', { token: null })
      })
  } else {
    store.dispatch('auth/token', { token: null })
  }
})

router.beforeEach((to, _from, next) => {
  if (to.matched.some(record => record.meta.requiresAuth)) {
    if (auth.currentUser) {
      const permissions = store.getters['auth/permissions'] || []
      const needPermission = to.meta.authRole || false
      const hasPermission = needPermission ? permissions.indexOf(needPermission) > -1 : true
      if (!hasPermission) {
        next({ path: '/' })
      }
      next()
    } else {
      next({
        path: '/login',
        query: { redirect: to.fullPath }
      })
    }
  } else {
    next()
  }
})