Golang HTML insert new line after a comma - go

Question

I'm so nearly there - my last step is to insert a new line after a comma (where there is one). For example, I have a table:
Country
City
Dates
Mexico
Playa Del Carmen
05-12-2019,06-12-2019,07-12-2019,08-12-2019,09-12-2019
French Polynesia
Papeete
16-11-2019
Rather than having all the dates on one line I want to insert a new line after each comma or better still replace the comma with a new line as below:
Country
City
Dates
Mexico
Playa Del Carmen
05-12-2019
ignore
ignore
06-12-2019
ignore
ignore
07-12-2019
ignore
ignore
08-12-2019
ignore
ignore
09-12-2019
French Polynesia
Papeete
16-11-2019
It doesn't need to be separate rows it can just be a list within the one row. The code I am using in golang html is:
<table>
<tr>
<th><b>Country</b></th>
<th><b>City</b></th>
<th><b>Dates</b></th>
</tr>
<tr>
<td>
<ul>
{{ range .TourCountry }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>
<td>
<ul>
{{ range .TourCity }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>
<td>
<ul>
{{ range .TourDateString }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>
</table>
The code I am using in the main.go file is:
func main() {
// static folder
fs := http.FileServer(http.Dir("static"))
http.Handle("/static/", http.StripPrefix("/static/", fs))
http.HandleFunc("/", mainPage)
http.HandleFunc("/concert", concertPage)
http.HandleFunc("/tour", tourPage)
http.HandleFunc("/about", aboutPage)
http.HandleFunc("/locations", locationsPage)
port := ":8080"
fmt.Println("Server listen on port localhost:8080")
err := http.ListenAndServe(port, nil)
if err != nil {
log.Fatal("Listen and Serve", err)
}
}
func tourPage(w http.ResponseWriter, r *http.Request) {
listOfIds := r.URL.Query()["id"]
id, err := strconv.Atoi(listOfIds[0])
if err != nil {
handle500(w)
}
ArtistsFull, _, _, _, _, _, _, err := GetData()
if err != nil || len(ArtistsFull) == 0 {
if err == nil {
err = errors.New("empty ArtistsFull from GetData")
}
fmt.Printf("GetData() error: %+v", err)
handle500(w)
}
artist, err := GetFullDataByID(id, ArtistsFull)
if err != nil {
fmt.Printf("GetFullDataByID(%d) error: %+v", id, err)
handle400(w)
}
tmpl, err := template.ParseFiles("tour.html")
if err != nil {
fmt.Printf("tour.html, error: %+v", err)
handle500(w)
}
if err := tmpl.Execute(w, artist); err != nil {
fmt.Printf("Tour Page Execute(w, artist) (%v) error: %+v/n", artist, err)
handle500(w)
}
}
Any ideas on how I can do this?

Answer 1

You can split the comma separated string in Go and then pass the resulting slice to the template. Or you can add custom template functions (with Funcs) that split the string in the template and then you can use that custom function within the template. Or you can define a method on the . value's type that does the split and then call that method within the template. As you can see you have at least 3 options, choose which ever you like best.
type Data struct {
TourDateString []string
}
var template_file = `<td>
<ul>
{{ range .TourDateString }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>`
func main() {
slice := strings.Split("05-12-2019,06-12-2019,07-12-2019,08-12-2019,09-12-2019", ",")
data := Data{slice}
t := template.Must(template.New("t").Parse(template_file))
if err := t.Execute(os.Stdout, data); err != nil {
panic(err)
}
}
https://go.dev/play/p/jx8u7dr8-G_z
type Data struct {
TourDateString string
}
var template_file = `<td>
<ul>
{{ range (split .TourDateString ",") }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>`
func main() {
data := Data{"05-12-2019,06-12-2019,07-12-2019,08-12-2019,09-12-2019"}
t := template.Must(template.New("t").Funcs(template.FuncMap{
"split": strings.Split,
}).Parse(template_file))
if err := t.Execute(os.Stdout, data); err != nil {
panic(err)
}
}
https://go.dev/play/p/IYqzF82WGgO
type Data struct {
TourDateString string
}
func (d Data) SplitTourDateString() []string {
return strings.Split(d.TourDateString, ",")
}
var template_file = `<td>
<ul>
{{ range .SplitTourDateString }}
<li>{{ . }}</li>
{{ end }}
</ul>
</td>`
func main() {
data := Data{"05-12-2019,06-12-2019,07-12-2019,08-12-2019,09-12-2019"}
t := template.Must(template.New("t").Parse(template_file))
if err := t.Execute(os.Stdout, data); err != nil {
panic(err)
}
}
https://go.dev/play/p/Fnr42ZbvlfH