Beego Session Not Passing Data to Template Automatically

Upon getting session information of type map[string]interface{} with this.GetSession("session_key"), I did have to explicitly set the context and type assert the session like this in order to explicitly pass the data to the template.

// Get the session
profile := this.GetSession("profile")

// Have to add data to the template's context
this.Data["nickname"] = profile.(map[string]interface{})["nickname"].(string)
this.Data["picture"] = profile.(map[string]interface{})["picture"].(string)

// Render template
this.TplNames = "user.html"

The session data (type map[string]interface{}) looks like this:

{"nickname": "joe", "picture": "urltotheimg"}

However, according to the Beego's session <a href="http://beego.me/docs/mvc/controller/session.md">doc</a>, it looks like the session is passed implicitly without any need of type assertions or context passing (the template has immediate access to session values i.e. {{.nickname}} and {{.picture}})

This is the controller setting the session before redirecting to /user

// Inherit beego's base controller
type MyController struct {
    beego.Controller
}

func (this *MyController) Get() {

    // code for getting token here

    // Getting the User information
    client := conf.Client(oauth2.NoContext, token)
    resp, err := client.Get("https://" + domain + "/userinfo")
    if err != nil {
	    this.Redirect("/error", 500)
        return
    }

    // Reading the body for user's information
    raw, err := ioutil.ReadAll(resp.Body)
    defer resp.Body.Close()
    if err != nil {
	    this.Redirect("/error", 500)
	    return
    }

    // Unmarshalling the JSON of the Profile
	var profile map[string]interface{}
	if err := json.Unmarshal(raw, &profile); err != nil {
		this.Redirect("/error", 500)
		return
	}

	// Saving the information to the session.
	this.SetSession("profile", profile)
    
	// redirect to /user
	this.Redirect("/user", 301)
}

This is the controller of "/user"

type UserController struct {
    beego.Controller
}

func (this *UserController) Get() {
    // get the saved session
    profile := this.GetSession("profile")
    
    // without setting the template data here, the session data won't be
    // available in user.html
    this.Data["nickname"] = profile.(map[string]interface{})["nickname"].(string)
    this.Data["picture"] = profile.(map[string]interface{})["picture"].(string)
    this.TplNames = "user.html"
}

Only this then I can map the template to the data like this:

<img src="{{ .picture }}">
<p>Hello, {{ .nickname }}</p>

I'm quite sure it's necessary to set the template data. I'm just not sure why the above doc didn't do that.

Any help would be appreciated.

I just tried running the Beego quickstart project and ran it successfully.

Make sure you have both the beego and bee installed. After creating a new project with bee new projectname make sure you edit the projectname/conf/app.conf file and add the sessionon = true:

appname = quickstart
httpport = 8080
runmode = dev
sessionon = true

I created a redirect controller like:

type RedirectController struct {
	beego.Controller
}

func (c *RedirectController) Get() {
	profile := make(map[string]interface{})
	profile["nickname"] = "User's Nickname"
	profile["picture"] = "/path/to/img.jpg"

	c.SetSession("profile", profile)
	c.Redirect("/", 301)
}

The main controller:

type MainController struct {
	beego.Controller
}

func (c *MainController) Get() {
	profile := c.GetSession("profile")

	c.Data["nickname"] = profile.(map[string]interface{})["nickname"]
	c.Data["picture"] = profile.(map[string]interface{})["picture"]
	c.TplNames = "index.tpl"
}

My index.tpl file:

<p>Nickname: {{.nickname}}</p>
<p>Picture: {{.picture}}</p>

And the router:

func init() {
	beego.Router("/", &controllers.MainController{})
	beego.Router("/redirect", &controllers.RedirectController{})
}

I would also recommend you to use a structure to store the profile values like:

// Define struct.
type Profile struct{
    Nickname string
    Picture  string
}

// Save it for template rendering.
this.Data["profile"] = &Profile{Nickname:"astaxie", Picture:"img.jpg"}

// And render it like this:
Nickname: {{.profile.Nickname}}
Picture:  {{.profile.Picture}}

Make sure to read this to understand how template rendering is done. I hope this is what you were asking for, if not, please edit your question and add more helpful information and I will edit this answer.