1 files changed, 75 insertions, 0 deletions
diff --git a/doc/articles/wiki/part3-errorhandling.go b/doc/articles/wiki/part3-errorhandling.go
new file mode 100644
index 000000000..945aa1e39
--- /dev/null
+++ b/doc/articles/wiki/part3-errorhandling.go
@@ -0,0 +1,75 @@
+// 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 (
+	"html/template"
+	"io/ioutil"
+	"net/http"
+)
+
+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
+}
+
+const lenPath = len("/view/")
+
+func renderTemplate(w http.ResponseWriter, tmpl string, p *Page) {
+	t, _ := template.ParseFiles(tmpl + ".html")
+	t.Execute(w, p)
+}
+
+func viewHandler(w http.ResponseWriter, r *http.Request) {
+	title := r.URL.Path[lenPath:]
+	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 := r.URL.Path[lenPath:]
+	p, err := loadPage(title)
+	if err != nil {
+		p = &Page{Title: title}
+	}
+	renderTemplate(w, "edit", p)
+}
+
+func saveHandler(w http.ResponseWriter, r *http.Request) {
+	title := r.URL.Path[lenPath:]
+	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 main() {
+	http.HandleFunc("/view/", viewHandler)
+	http.HandleFunc("/edit/", editHandler)
+	http.HandleFunc("/save/", saveHandler)
+	http.ListenAndServe(":8080", nil)
+}