router.beforeEach((to, from, next) => {
  NProgress.start()
  if (getToken()) {
    to.meta.title && store.dispatch('settings/setTitle', to.meta.title)
    /* has token*/
    if (to.path === '/login') {
      next({ path: '/' })
      NProgress.done()
    } else {
      if (store.getters.roles.length === 0) {
        isRelogin.show = true
        // 判断当前用户是否已拉取完user_info信息
        store.dispatch('GetInfo').then(() => {
          isRelogin.show = false
          store.dispatch('GenerateRoutes').then(accessRoutes => {
            // 根据roles权限生成可访问的路由表
            router.addRoutes(accessRoutes) // 动态添加可访问路由表
            next({ ...to, replace: true }) // hack方法 确保addRoutes已完成
          })
        }).catch(err => {
            store.dispatch('LogOut').then(() => {
              Message.error(err)
              next({ path: '/' })
            })
          })
      } else {
        next()
      }
    }
  } else {
    // 没有token
    if (whiteList.indexOf(to.path) !== -1) {
      // 在免登录白名单，直接进入
      next()
    } else {
      next(`/login?redirect=${to.fullPath}`) // 否则全部重定向到登录页
      NProgress.done()
    }
  }
})

在前置路由守卫中会调用GenerateRoutes方法

// 生成路由
    GenerateRoutes({ commit }) {
      return new Promise(resolve => {
        // 向后端请求路由数据
        getRouters().then(res => {
          const sdata = JSON.parse(JSON.stringify(res.data))
          const rdata = JSON.parse(JSON.stringify(res.data))
          const sidebarRoutes = filterAsyncRouter(sdata)
          const rewriteRoutes = filterAsyncRouter(rdata, false, true)
          const asyncRoutes = filterDynamicRoutes(dynamicRoutes);
          rewriteRoutes.push({ path: '*', redirect: '/404', hidden: true })
          router.addRoutes(asyncRoutes);
          commit('SET_ROUTES', rewriteRoutes)
          commit('SET_SIDEBAR_ROUTERS', constantRoutes.concat(sidebarRoutes))
          commit('SET_DEFAULT_ROUTES', sidebarRoutes)
          commit('SET_TOPBAR_ROUTES', sidebarRoutes)
          resolve(rewriteRoutes)
        })
      })
    }

此方法会请求接口，返回权限数据拼接处理后调用router.addRoutes（）将页面添加到路由中。

 commit('SET_SIDEBAR_ROUTERS', constantRoutes.concat(sidebarRoutes)) 加会将常量路由（不需要权限）和动态获取的权限路由拼接起来保存，供侧边栏遍历渲染菜单。

 

现在进入后端的getRougters方法：

/**
     * 获取路由信息
     * 
     * @return 路由信息
     */
    @GetMapping("getRouters")
    public AjaxResult getRouters()
    {
        Long userId = SecurityUtils.getUserId();
        List<SysMenu> menus = menuService.selectMenuTreeByUserId(userId);
        return AjaxResult.success(menuService.buildMenus(menus));
    }

上来先拿到userId，通过id获取菜单

@Override
    public List<SysMenu> selectMenuTreeByUserId(Long userId)
    {
        List<SysMenu> menus = null;
        if (SecurityUtils.isAdmin(userId))
        {
            menus = menuMapper.selectMenuTreeAll();
        }
        else
        {
            menus = menuMapper.selectMenuTreeByUserId(userId);
        }
        return getChildPerms(menus, 0);
    }

同样超级管理员拿到写死的最高权限

<select id="selectMenuTreeByUserId" parameterType="Long" resultMap="SysMenuResult">
		select distinct m.menu_id, m.parent_id, m.menu_name, m.path, m.component, m.`query`, m.visible, m.status, ifnull(m.perms,'') as perms, m.is_frame, m.is_cache, m.menu_type, m.icon, m.order_num, m.create_time
		from sys_menu m
			 left join sys_role_menu rm on m.menu_id = rm.menu_id
			 left join sys_user_role ur on rm.role_id = ur.role_id
			 left join sys_role ro on ur.role_id = ro.role_id
			 left join sys_user u on ur.user_id = u.user_id
		where u.user_id = #{userId} and m.menu_type in ('M', 'C') and m.status = 0  AND ro.status = 0
		order by m.parent_id, m.order_num
</select>

通过以上sql语句拿到数据，在表设计中M表示目录，C表示菜单。

 

2、按钮权限

也就是所需要system:dept:add当前按钮才会显示

 

 

 

 

 

 

2.1、v-hasPermi

 

注册全局自定义指令

Vue.directive('hasPermi', hasPermi)

import store from '@/store'

export default {
  inserted(el, binding, vnode) {
    const { value } = binding
    const all_permission = "*:*:*";
    const permissions = store.getters && store.getters.permissions

    if (value && value instanceof Array && value.length > 0) {
      const permissionFlag = value

      const hasPermissions = permissions.some(permission => {
        return all_permission === permission || permissionFlag.includes(permission)
      })

      if (!hasPermissions) {
        el.parentNode && el.parentNode.removeChild(el)
      }
    } else {
      throw new Error(`请设置操作权限标签值`)
    }
  }
}

通过el拿到当前dom节点

value为传过来的权限"system:dept:add",

vuex中拿到之前存的所有权限

if (!hasPermissions) {
    el.parentNode && el.parentNode.removeChild(el)
}

对比判读如果没有当前权限就直接移除当前dom