Mastering Beego Controllers in Go: From Basics to Advanced Methods

Beego Controller Overview

In Beego’s MVC architecture the Controller type handles HTTP requests, mediates between models and view templates, and provides a lifecycle of hooks.

Creating a Controller

Define a struct that anonymously embeds beego.Controller and import the package github.com/astaxie/beego (or github.com/beego/beego/v2/server/web for newer versions).

type MyController struct {
    beego.Controller
}

Typical Handler Implementation

Implement HTTP‑method functions (e.g., Get) on the struct. Inside the method you can populate c.Data (a map[interface{}]interface{}) with values that the template can use, and set c.TplName to the template file.

package controllers

import (
    "github.com/astaxie/beego"
)

type MainController struct {
    beego.Controller
}

// GET / route
func (c *MainController) Get() {
    c.Data["Website"] = "beego.me"
    c.Data["Email"]   = "[email protected]"
    c.TplName = "index.tpl"
}

If beego.AutoRender is true (default), Beego automatically calls Render() after the handler finishes, so the template is rendered without an explicit call.

Direct Response

When a template is not needed you can write directly to the response body:

func (c *MainController) Get() {
    c.Ctx.WriteString("hello")
}

Controller Core Structure

type Controller struct {
    // request/response context
    Ctx  *context.Context
    Data map[interface{}]interface{}

    // routing metadata
    controllerName string
    actionName     string
    methodMapping  map[string]func()
    gotofunc       string
    AppController  interface{}

    // template configuration
    TplName        string
    ViewPath       string
    Layout         string
    LayoutSections map[string]string
    TplPrefix      string
    TplExt         string
    EnableRender   bool

    // XSRF protection
    _xsrfToken string
    XSRFExpire int
    EnableXSRF bool

    // session store
    CruSession session.Store
}

ControllerInterface

type ControllerInterface interface {
    Init(ct *context.Context, controllerName, actionName string, app interface{})
    Prepare()
    Get()
    Post()
    Delete()
    Put()
    Head()
    Patch()
    Options()
    Finish()
    Render() error
    XSRFToken() string
    CheckXSRFCookie() bool
    HandlerFunc(fn string) bool
    URLMapping()
}

Lifecycle Hooks

Init : called by the framework before any request handling; it sets Ctx, controller name, action name, initializes Data, and stores a reflected reference to the concrete controller.

Prepare : runs after Init and before the specific HTTP‑method handler; useful for authentication, logging, or request preprocessing.

Get / Post / Delete / Put / Head / Patch / Options : correspond to the respective HTTP verbs. The default implementation returns HTTP 405; overriding them provides custom logic.

Finish : executed after the HTTP‑method handler (and after Render if enabled); ideal for resource cleanup such as closing DB connections.

Render : renders the template identified by TplName when EnableRender (or global beego.AutoRender) is true.

Template Resolution

If TplName is not set, Beego falls back to a file named controller/<lowercase‑method>.tpl under the view directory (e.g., maincontroller/get.tpl).

References

Beego source repository:

github.com/astaxie/beego