结合了文件读写和web服务器的小练习

初步提供读取功能

package main

import (
	"fmt"
	"log"
	"net/http"
	"os"
)

type Page struct {
	Title string
	Body  []byte
}

func (p *Page) save() error {
	filename := p.Title + ".txt"
	return os.WriteFile(filename, p.Body, 0600)
}

func loadPage(title string) (*Page, error) {
	filename := title + ".txt"
	body, _ := os.ReadFile(filename)
	return &Page{Title: title, Body: body}, nil
}

func viewHandler(w http.ResponseWriter, r *http.Request) {
	title := r.URL.Path[len("/view/"):]
	p, _ := loadPage(title)
	fmt.Fprintf(w, "<h1>%s</h1><div>%s</div>", p.Title, p.Body)

}

func main() {
	http.HandleFunc("/view/", viewHandler)
	log.Fatal(http.ListenAndServe(":8080", nil))
}

完善所有功能

用上了 html/template 包

wiki.go

package main

import (
	"html/template"
	"log"
	"net/http"
	"os"
)

type Page struct {
	Title string
	Body  []byte
}

func (p *Page) save() error {
	filename := p.Title + ".txt"
	return os.WriteFile(filename, p.Body, 0600)
}

func loadPage(title string) (*Page, error) {
	filename := title + ".txt"
	body, _ := os.ReadFile(filename)
	return &Page{Title: title, Body: body}, nil
}

func viewHandler(w http.ResponseWriter, r *http.Request) {
	title := r.URL.Path[len("/view/"):]
	p, _ := loadPage(title)
	t, _ := template.ParseFiles("view.html")
	t.Execute(w, p)
}

func editHandler(w http.ResponseWriter, r *http.Request) {
	title := r.URL.Path[len("/edit/"):]
	p, err := loadPage(title)
	if err != nil {
		// p = &Page{Title: title, Body: []byte{}}
		// 如果页面不存在，重定向到编辑页面
		http.Redirect(w, r, "/edit/"+title, http.StatusFound)
	}

	// fmt.Fprintf(w, "<h1>Editing %s</h1>"+
	// 	"<form action=\"/save/%s\" method=\"POST\">"+
	// 	"<textarea name=\"body\">%s</textarea><br>"+
	// 	"<input type=\"submit\" value=\"Save\">"+
	// 	"</form>",
	// 	p.Title, p.Title, p.Body)

	// 使用template包来渲染HTML模板
	t, _ := template.ParseFiles("edit.html")
	t.Execute(w, p)
}

func saveHandler(w http.ResponseWriter, r *http.Request) {
	title := r.URL.Path[len("/save/"):]
	body := r.FormValue("body")
	p := &Page{Title: title, Body: []byte(body)}
	p.save()
	http.Redirect(w, r, "/view/"+title, http.StatusFound)
}

func main() {
	http.HandleFunc("/view/", viewHandler)
	http.HandleFunc("/edit/", editHandler)
	http.HandleFunc("/save/", saveHandler)
	log.Fatal(http.ListenAndServe(":8080", nil))
}

edit.html

<h1>Editing {{.Title}}</h1>

<form action="/save/{{.Title}}" method="POST">
<div><textarea name="body" rows="20" cols="80">{{printf "%s" .Body}}</textarea></div>
<!-- printf 保证输出的是字符串，而不是字节流 -->
<div><input type="submit" value="Save"></div>
</form>

view.html

<h1>{{.Title}}</h1>

<p>[<a href="/edit/{{.Title}}">edit</a>]</p>

<div>{{printf "%s" .Body}}</div>