Go中的多部分http请求

POST /upload HTTP/1.1
Host: example.com
Content-Type: multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW

------WebKitFormBoundary7MA4YWxkTrZu0gW
Content-Disposition: form-data; name="file"; filename="example.txt"
Content-Type: text/plain

This is the content of the file.

------WebKitFormBoundary7MA4YWxkTrZu0gW
Content-Disposition: form-data; name="name"

John Doe
------WebKitFormBoundary7MA4YWxkTrZu0gW--

package main

import (
	"fmt"
	"io"
	"log"
	"mime/multipart"
	"net/http"
	"os"
)

func handleUpload(w http.ResponseWriter, r *http.Request) {
	err := r.ParseMultipartForm(32 << 20) // 解析请求体，限制最大32MB
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	file, handler, err := r.FormFile("file") // 获取上传的文件
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	defer file.Close()

	// 将文件保存到本地
	f, err := os.OpenFile(handler.Filename, os.O_WRONLY|os.O_CREATE, 0666)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	defer f.Close()

	_, err = io.Copy(f, file)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	fmt.Fprintln(w, "File uploaded successfully.")
}

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