blob: b4ce2557426a8376d6af733ffea8ae74b1d1ad32 [file] [log] [blame]
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
import (
"errors"
"html/template"
"io/ioutil"
"log"
"net/http"
"regexp"
)
type Page struct {
Title string
Body []byte
}
func (p *Page) save() error {
filename := p.Title + ".txt"
return ioutil.WriteFile(filename, p.Body, 0600)
}
func loadPage(title string) (*Page, error) {
filename := title + ".txt"
body, err := ioutil.ReadFile(filename)
if err != nil {
return nil, err
}
return &Page{Title: title, Body: body}, nil
}
func viewHandler(w http.ResponseWriter, r *http.Request) {
title, err := getTitle(w, r)
if err != nil {
return
}
p, err := loadPage(title)
if err != nil {
http.Redirect(w, r, "/edit/"+title, http.StatusFound)
return
}
renderTemplate(w, "view", p)
}
func editHandler(w http.ResponseWriter, r *http.Request) {
title, err := getTitle(w, r)
if err != nil {
return
}
p, err := loadPage(title)
if err != nil {
p = &Page{Title: title}
}
renderTemplate(w, "edit", p)
}
func saveHandler(w http.ResponseWriter, r *http.Request) {
title, err := getTitle(w, r)
if err != nil {
return
}
body := r.FormValue("body")
p := &Page{Title: title, Body: []byte(body)}
err = p.save()
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
http.Redirect(w, r, "/view/"+title, http.StatusFound)
}
func renderTemplate(w http.ResponseWriter, tmpl string, p *Page) {
t, err := template.ParseFiles(tmpl + ".html")
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
err = t.Execute(w, p)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
var validPath = regexp.MustCompile("^/(edit|save|view)/([a-zA-Z0-9]+)$")
func getTitle(w http.ResponseWriter, r *http.Request) (string, error) {
m := validPath.FindStringSubmatch(r.URL.Path)
if m == nil {
http.NotFound(w, r)
return "", errors.New("Invalid Page Title")
}
return m[2], nil // The title is the second subexpression.
}
func main() {
http.HandleFunc("/view/", viewHandler)
http.HandleFunc("/edit/", editHandler)
http.HandleFunc("/save/", saveHandler)
log.Fatal(http.ListenAndServe(":8080", nil))
}