a simple upload form in go

gistfile1.go

package main

import (
    "fmt"
    "net/http"
    "text/template"
    "io"
    "io/ioutil"
)


var (
    templates = template.Must(template.ParseFiles(
            "upload.html",
            "view.html",
            "error.html",
    ))
)

func upload(w http.ResponseWriter, r *http.Request){
    if r.Method != "POST" {
        templates.ExecuteTemplate(w, "upload.html", nil)
        return
    }

    f, _, err := r.FormFile("image")
    handleError(err)
    defer f.Close()

    t, err := ioutil.TempFile("media/uploads", "image-")
    handleError(err)
    defer t.Close()

    _, err = io.Copy(t, f);
    handleError(err)
    http.Redirect(w, r, "/view?id="+ t.Name()[20:], 302)

}

func handleError (err error){
    if err != nil {
        panic(err)
    }
}

func view(w http.ResponseWriter, r *http.Request) {
    templates.ExecuteTemplate(w, "view.html", r.FormValue("id"))
}


func errorHandler(fn http.HandlerFunc) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request){
        defer func(){
            if e := recover(); e != nil {
                w.WriteHeader(500)
                templates.ExecuteTemplate(w, "error.html", e)
            }
        }()
        fn(w, r)
    }
}

func main() {
    http.HandleFunc("/", errorHandler(upload))
    http.HandleFunc("/view", errorHandler(view))
    http.HandleFunc("/media/", func(w http.ResponseWriter, r *http.Request) {
        http.ServeFile(w, r, r.URL.Path[1:])
        fmt.Fprintf(w, r.URL.Path[1:])
    })
    http.ListenAndServe(":8080", nil)
}