vue-element-template 获取后端路由表动态生成权限

主要思路如下：

• 用户登录login获取token
• 拿着token请求用户信息，同时后端返回一个路由表
• 前端解析后动态添加路由表，同时存储到本地localstorage
• 刷新页面或者退出登录或者登录过期等时，会进行相应的判断，重新渲染路由

1、在src/utils文件夹下新建_import.js，用于匹配组件，代码如下：

export default function (component) {
  switch (component) {
    case 'Layout':
      return require("@/layout").default
    case 'Test':
      return require('@/views/table/index').default
    default:
      return require('@/views/' + component + '/index').default
  }
}

 2、在src/utils文件夹下新建router.js，用于解析后端返回的路由，具体解析方法和数据形式还是要看项目具体来分析，代码如下：

import _import from "@/utils/_import"
export default function (routers) {
  return filterAsyncRouter(routers)
}
//将后台返回的json权限数据格式化（递归遍历子节点）
export const filterAsyncRouter = (asyncRouterMap) => { //遍历后台传来的路由字符串，转换为组件对象
  const accessedRouters = asyncRouterMap.filter(e => {
    if (e.component) {
      e.component = _import(e.component)
    }
    if (e.children && e.children.length) {
      e.children = filterAsyncRouter(e.children)
    }
    else
    {
      delete e.children;
    }
    if (e.redirect === '') {
          delete e.redirect
    }
    if (e.name === '') {
      delete e.name
    }

    if (e.meta.icon !== '' && e.meta.title !== '') { // 配置 菜单标题 与 图标
      e.meta = {
        title: e.meta.title,
        icon: e.meta.icon
      }
    } else if (e.meta.icon === '' && e.meta.title !== '') {
      e.meta = {
        title: e.meta.title
      }
    }

    return true
  })
  return accessedRouters
}

3,在src/store/modules/user.js下添加menus,用于保存后端返回的路由，代码如下：

import { login, logout, getInfo } from '@/api/user'
import { getToken, setToken, removeToken } from '@/utils/auth'
import { resetRouter } from '@/router'
import Layout from '@/layout'
import routerFormat from '@/utils/router'

const getDefaultState = () => {
  return {
    token: getToken(),
    name: '',
    avatar: '',
    roles: [],
    menus: "",   //新增
  }
}

const state = getDefaultState()

const mutations = {
  RESET_STATE: (state) => {
    Object.assign(state, getDefaultState())
  },
  SET_TOKEN: (state, token) => {
    state.token = token
  },
  SET_NAME: (state, name) => {
    state.name = name
  },
  SET_AVATAR: (state, avatar) => {
    state.avatar = avatar
  },
  SET_ROLES: (state, roles) => {
    state.roles = roles
  },
  SET_MENUS: (state, menus) => {　　　　//赋值menus
      state.menus = menus
   }
}

const actions = {
  // user login
  login({ commit }, userInfo) {
    const { username, password } = userInfo
    return new Promise((resolve, reject) => {
      login({ username: username.trim(), password: password }).then(response => {
        const { data } = response
        commit('SET_TOKEN', data.AccessToken)
        setToken(data.AccessToken)
        resolve()
      }).catch(error => {
        reject(error)
      })
    })
  },

  // get user info
  getInfo({ commit, state }) {
    return new Promise((resolve, reject) => {
      getInfo(state.token).then(response => {
        const { data } = response
        if (!data) {
          reject('Verification failed, please Login again.')
        }

        const { roles, name, avatar,menus   } = data

        const routes = routerFormat(menus);                           //格式化后端返回的菜单
        routes.push({ path: '*', redirect: '/404', hidden: true });   //插入404页面

        // roles must be a non-empty array
        if (!roles || roles.length <= 0) {
          reject('getInfo: roles must be a non-null array!')
        }

        commit('SET_ROLES', roles)
        commit('SET_NAME', name)
        commit('SET_AVATAR', avatar)
        commit("SET_MENUS", routes) // 触发vuex SET_MENUS 保存路由表到vuex
        resolve(data)
      }).catch(error => {
        reject(error)
      })
    })
  },

  // user logout
  logout({ commit, state }) {
    return new Promise((resolve, reject) => {
      logout(state.token).then(() => {
        removeToken() // must remove  token  first
        resetRouter()
        commit('RESET_STATE')
        resolve()
      }).catch(error => {
        reject(error)
      })
    })
  },

  // remove token
  resetToken({ commit }) {
    return new Promise(resolve => {
      removeToken() // must remove  token  first
      commit('RESET_STATE')
      resolve()
    })
  }
}

export default {
  namespaced: true,
  state,
  mutations,
  actions
}

4,修改src/store/modules/permission.js,直接显示后端的路由，不过滤

const actions = {
  generateRoutes({ commit }, accessedRoutes) {
    return new Promise(resolve => { 
      commit('SET_ROUTES', accessedRoutes)
      resolve(accessedRoutes)
    })
  }
}

5,修改src/permission.js，

import router from './router'
import store from './store'
import { Message } from 'element-ui'
import NProgress from 'nprogress' // progress bar
import 'nprogress/nprogress.css' // progress bar style
import { getToken } from '@/utils/auth' // get token from cookie
import getPageTitle from '@/utils/get-page-title'
const _import = require('./router/_import_' + process.env.NODE_ENV)

NProgress.configure({ showSpinner: false }) // NProgress Configuration

const whiteList = ['/login'] // no redirect whitelist

router.beforeEach(async(to, from, next) => {
  // start progress bar
  NProgress.start()

  // set page title
  document.title = getPageTitle(to.meta.title)

  // determine whether the user has logged in
  const hasToken = getToken()

  if (hasToken) {

    if (to.path === '/login') {
      // if is logged in, redirect to the home page
      next({ path: '/' })
      NProgress.done()
    } else {
      // determine whether the user has obtained his permission roles through getInfo
      const hasRoles = store.getters.roles && store.getters.roles.length > 0
      if (hasRoles) {
        next()
      } else {
        try {
          // get user info
          // note: roles must be a object array! such as: ['admin'] or ,['developer','editor']
          const { roles } = await store.dispatch('user/getInfo')
          // generate accessible routes map based on roles
          const accessRoutes = await store.dispatch('permission/generateRoutes', store.getters.menus)
           router.addRoutes(accessRoutes)   //添加生成的路由，不添加会出现找不倒路由的问题

          // hack method to ensure that addRoutes is complete
          // set the replace: true, so the navigation will not leave a history record
          next({ ...to, replace: true })
        } catch (error) {
          // remove token and go to login page to re-login
          await store.dispatch('user/resetToken')
          Message.error(error || 'Has Error')
          next(`/login?redirect=${to.path}`)
          NProgress.done()
        }
      }
    }
  } else {
    /* has no token*/

    if (whiteList.indexOf(to.path) !== -1) {
      // in the free login whitelist, go directly
      next()
    } else {
      // other pages that do not have permission to access are redirected to the login page.
      next(`/login?redirect=${to.path}`)
      NProgress.done()
    }
  }
})

router.afterEach(() => {
  // finish progress bar
  NProgress.done()
})