Go template.ExecuteTemplate include html

Peter picture Peter · Aug 11, 2013 · Viewed 29.6k times · Source

I have followed this tutorial: http://golang.org/doc/articles/wiki/final.go and have slightly modified it for my needs/wants. The problem is I would like to support HTML in the templates. I realize this is a security risk but it's not a concern at the moment.

The result of a page render:

<h1>this<strong>is</strong>a test</h1>

Let me explain a little bit of the code:

type Page struct {
    Title string
    Body  []byte
}

The data I would like to have HTML is stored in Page.Body. This is type []byte which means I can't (or can I?) run html/template.HTML(Page.Body) as that function expects a string.

I have this which pre-renders the templates:

var (
    templates = template.Must(template.ParseFiles("tmpl/edit.html", "tmpl/view.html"))
)

And the actual ExecuteTemplate looks like this:

err := templates.ExecuteTemplate(w, tmpl+".html", p)

Where w is w http.ResponseWriter, tmpl is tmpl string, and p is p *Page

Finally my 'view.html' (template) looks like the following:

<h1>{{.Title}}</h1>
<p>[<a href="/edit/{{.Title}}">edit</a>]</p>
<div>{{printf "%s" .Body}}</div>

Things I have tried:

  • {{printf "%s" .Body | html}} doesn't do anything
  • I have included github.com/russross/blackfriday (Markdown processor) and have run p.Body = blackfriday.MarkdownCommon(p.Body) which correctly converts Markdown to HTML, but the HTML is still output as entities.
  • EDIT: I have attempted the following bit of code (I don't know why the format is messed up) and it still outputs the exact same.

    var s template.HTML s = template.HTML(p.Body) p.Body = []byte(s)

Any guidance is greatly appreciated. If I'm being confusing please ask and I can modify my question.

Answer

thwd picture thwd · Aug 12, 2013

Convert your []byte or string to type template.HTML (documented here)

p.Body = template.HTML(s) // where s is a string or []byte

Then, in your template, just:

{{.Body}}

It will be printed without escaping.

EDIT

In order to be able to include HTML in you page's body you need to change the Page type declaration:

type Page struct {
    Title string
    Body  template.HTML
}

then assign to it.