Cannot bind mysql data to html template in golang

UPDATE: There is no error from anywhere whatsoever! In the browser, there is no error in the console or network tab. In the terminal running the go code, there is no error either. All errors in go are logged; for brevity I removed the error handling in the question.

Trying to follow a book about writing web app using Go.
I have a local mysql db which I can get data from using database/sql package. I am parsing the template using html/template package but somehow can't bind the data into the template.

This is the model:

type Snippet struct {
	ID      int
	Title   string
	Content string
	Created time.Time
	Expires time.Time
}

This is the handler for showing the data (error handling is omitted):

func (app *application) showSnippet(w http.ResponseWriter, r *http.Request) {
	id, _ := strconv.Atoi(r.URL.Query().Get("id"))
	s, _ := app.snippets.Get(id) // get data from database!
	files := []string{
		"./ui/html/show.page.tmpl", // this is the template.
		"./ui/html/base.layout.tmpl",
		"./ui/html/footer.partial.tmpl", // either relative or absolute path!
	}
	ts, _ := template.ParseFiles(files...)
	_ = ts.Execute(w, s) // write the template set content as the response body; 
	
	// NOTE: this does print out data fine so data is indeed retrieved from the db.
	fmt.Fprintf(w, "%s\n%s", s.Title, s.Content) 
}

Here is the show.page.tmpl template:

{{template "base" .}}
{{define "title"}}Snippet #{{.ID}}{{end}}
{{define "main"}}
<div class='snippet'>
    <div class='metadata'>
        <strong>{{.Title}}</strong>
        <span>#{{.ID}}</span>
    </div>
    <pre><code>{{.Content}}</code></pre>
    <div class='metadata'>
        <time>Created: {{.Created}}</time>
        <time>Expires: {{.Expires}}</time>
    </div>
</div>
{{end}}

On the page, it doesn't display the data as it's empty; but the debug line is printed fine at the bottom.
What went wrong?

It's not a good idea to compile the templates in the HTTP handler (basically in every request)

Assuming you created the files with the template names and an .htm extension, you can do something like this (or even add them to the application struct)

// Define a global templates variable (or add it to the application if you want)
var templates *template.Template
// For compiling the templates
// in a subdirectory called "templates" with files ending in .htm
func getTemplates() (templates *template.Template, err error) {
var allFiles []string
templateDir := "templates"
files2, _ := ioutil.ReadDir(templateDir)
for _, file := range files2 {
filename := file.Name()
if strings.HasSuffix(filename, ".htm") {
filePath := filepath.Join(templateDir, filename)
allFiles = append(allFiles, filePath)
}
}
templates, err = template.New("").ParseFiles(allFiles...)
LogPanic(err, "Error building templates")
return
}
// load them on init
func init() {
var err error
templates, err = getTemplates()
if err != nil {
log.Panicf("%s: %s \n", "ERROR compiling templates", err)
}
}

Now that you have the templates compiled, you can execute them in the HTTP handler, and log the error if there's any (please share if you see any errors as Cerise Limón suggested) remember to update the template name in the code.

func (app *application) showSnippet(w http.ResponseWriter, r *http.Request) {
id, _ := strconv.Atoi(r.URL.Query().Get("id"))
s, _ := app.snippets.Get(id)
err := templates.ExecuteTemplate(w, "template_name", s)
if err != nil {
log.Printf("%s: %s \n", "ERROR executing template", err)
}
fmt.Fprintf(w, "%s\n%s", s.Title, s.Content) 
}