vue路由守卫配合权限，白名单

router.beforeEach(async(to, from, next) => {
      // 进度条开始
      NProgress.start()
    
    
      // 确认用户是否已登录（获取它的token值，这里的getToken()是封装好的一个方法）
      const hasToken = getToken()
    
    
      if (hasToken) {//如果有token，说明是登录状态
        if (to.path === '/login') {//路由是/login页，那么直接跳转到首页
          next({ path: '/' })
          NProgress.done()  //进度条结束
        } else {//如果不是登录页
          // 确定用户是否已通过getInfo获得其权限角色
          const hasRoles = store.getters.roles && store.getters.roles.length > 0
          if (hasRoles) {//如果通过角色权限，继续访问
            next()      
          } else {//如果没有通过角色权限
            // alert('没有role')
            console.log('获取角色')
            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', roles)
    
              // dynamically add accessible routes
              router.addRoutes(accessRoutes)
    
              // 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 {//如果没有token
        /* has no token*/
        // alert('没有token to.path=' + to.path)
    
        if (whiteList.indexOf(to.path) !== -1) {//白名单中有的路由，可以继续访问
          // in the free login whitelist, go directly
          next()
        } else {//否则，白名单中没有的路由，跳回首页
          // other pages that do not have permission to access are redirected to the login page.
          next(`/login?redirect=${to.path}`)
          NProgress.done()
        }
      }
    })