Basic HTTP File Upload server written in Go without JavaScript, saving files as their MD5 hash + extention (if it exists)

server.go

package main

import (
	"crypto/md5"
	"encoding/hex"
	"io"
	"net/http"
	"os"
	"strings"
)

func main() {
	os.Mkdir("uploads", 0777)
	http.HandleFunc("/", handle)
	if err := http.ListenAndServe(":80", nil); err != nil {
		panic(err)
	}
}

func handle(w http.ResponseWriter, r *http.Request) {
	if r.Method == "POST" {
		r.ParseMultipartForm(100000)
		file, handler, err := r.FormFile("file")
		if err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
		defer file.Close()
		hash := md5.New()
		io.Copy(hash, file)
		hashString := hex.EncodeToString(hash.Sum(nil))
		if strings.Contains(handler.Filename, ".") {
			hashString = hashString + handler.Filename[strings.LastIndex(handler.Filename, "."):len(handler.Filename)]
		}
		f, _ := os.Create("uploads/" + hashString)
		defer f.Close()
		file.Seek(0, 0)
		io.Copy(f, file)
		w.WriteHeader(http.StatusCreated)
		w.Write([]byte("<a href=\"" + hashString + "\">" + hashString + "</a>"))
		return
	}
	if r.URL.Path != "/" {
		if _, err := os.Stat("uploads/" + r.URL.Path[1:len(r.URL.Path)]); err == nil {
			http.ServeFile(w, r, "uploads/"+r.URL.Path[1:len(r.URL.Path)])
			return
		}
		http.Error(w, "404 Not Found", http.StatusNotFound)
		return
	}
	w.Write([]byte("<p><form enctype=\"multipart/form-data\" method=\"post\"><input type=\"file\" name=\"file\"/><input type=\"submit\"/></form>"))
}