name: Global Variables

sort: 5

Global Variables

Variables common to all requests can be added using a base controller using the Prepare method.

Usage examples include the username of the current user for display in a toolbar or the request URL for highlighting active menu items.

First, create a common/base controller in the controllers package:

  2. app_root
  3. ├── controllers
  4. │   ├── base.go <-- base controller
  5. │   └── default.go
  6. └── main.go

Your base controller should embed the web.Controller from github.com/beego/beego/v2/server/web. From here, the Prepare method should be defined, containing any logic required for global variables:

  2. // app_root/controllers/base.go
  3. package controllers
  5. import (
  6.     "github.com/beego/beego/v2/server/web"
  7. )
  9. type BaseController struct {
  10.     web.Controller
  11. }
  13. // Runs after Init before request function execution
  14. func (c *BaseController) Prepare() {
  15.     c.Data["RequestUrl"] = c.Ctx.Input.URL()
  16. }
  18. // Runs after request function execution
  19. func (c *BaseController) Finish() {
  20.     // Any cleanup logic common to all requests goes here. Logging or metrics, for example.
  21. }

All other controllers should embed BaseController instead of web.Controller:

  2. // app_root/controllers/default.go
  3. package controllers
  5. type DefaultController struct {
  6.     BaseController
  7. }
  9. func (c *DefaultController) Index() {
  10.     // your controller logic
  11. }

From here your views can access these global variables, in both individual templates and all parent templates:

  1. <div>{{ $.RequestUrl }}</div>