multipart/form-data 中有 boundary，该怎么写？

[Bisns]

multipart/form-data 中有 boundary，该怎么写？

[duke-git]

multipart/form-data 中有 boundary，该怎么写？

@Bisns 使用writer.FormDataContentType 设置Content-Type header 为 multipart/form-data; boundary=xxx 。参考代码：

• server.go

package main

import (
	"io"
	"log"
	"net/http"
)

func main() {
	http.HandleFunc("/upload", handleUploadFile)
	http.ListenAndServe(":8090", nil)
}

func handleUploadFile(w http.ResponseWriter, r *http.Request) {
	log.Println("Content-Type: ", r.Header.Get("Content-Type"))

	if err := r.ParseMultipartForm(0); err != nil {
		log.Fatal(err)
		return
	}

	log.Println("FormValue(username):    ", r.FormValue("username"))
	log.Println("FormValue(password):     ", r.FormValue("password"))
	log.Println("PostFormValue(username):", r.PostFormValue("username"))
	log.Println("PostFormValue(password): ", r.PostFormValue("password"))

	// log.Println("MultipartForm: ", r.MultipartForm)

	// file, header, err := r.FormFile("file")
	// log.Println("FormFile(file): ", file, header, err)

	w.Header().Set("Content-Type", "text/json")

	io.WriteString(w, "ok")
}

• client.go

package main

import (
	"bytes"
	"fmt"
	"io"
	"log"
	"mime/multipart"
	"net/http"
	"os"
	"path/filepath"

	"github.com/duke-git/lancet/v2/netutil"
)

func main() {
	UploadFile()
}

func UploadFile() {
	file, _ := os.Open("./test.txt")
	defer file.Close()

	body := &bytes.Buffer{}
	writer := multipart.NewWriter(body)

	part, err := writer.CreateFormFile("file", filepath.Base(file.Name()))
	if err != nil {
		log.Fatal(err)
	}

	io.Copy(part, file)

	writer.WriteField("username", "test")
	writer.WriteField("password", "123456")

	err = writer.Close()
	if err != nil {
		log.Fatal(err)
	}

	header := http.Header{}
	header.Add("Content-Type", writer.FormDataContentType())

	req := &netutil.HttpRequest{
		RawURL:  "http://127.0.0.1:8090/upload",
		Method:  "POST",
		Headers: header,
		Body:    body.Bytes(),
	}

	client := netutil.NewHttpClient()

	resp, err := client.SendRequest(req)
	if err != nil {
		log.Fatal(err)
	}
	defer resp.Body.Close()

	s, _ := io.ReadAll(resp.Body)

	fmt.Println("response: ", string(s)) //ok
}