golang http 上传文件记录

// 测试客户端上传文件

package main

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

func main() {
    //err := post()
    err := postBigFile()
    if err != nil {
        fmt.Println(err)
    }
}

func post() error {
    //读文件
    path := "F:\\test\\hello.html"
    targetUrl := "http://localhost:9090/upload"

    bodyBuf := new(bytes.Buffer)

    bodyWriter := multipart.NewWriter(bodyBuf)
    fileWriter, err := bodyWriter.CreateFormFile("userfile", path)

    if err != nil {
        fmt.Println("error writing to buffer")
        return err
    }

    fh, err := os.Open(path)
    if err != nil {
        fmt.Println("error opening file")
        return err
    }
    defer fh.Close()
    //iocopy (大文件性能呢!)
    _, err = io.Copy(fileWriter, fh)
    if err != nil {
        return err
    }
    contentType := bodyWriter.FormDataContentType()

    bodyWriter.WriteField("xxxx", "yyyy")
    bodyWriter.WriteField("1111", "2222")

    bodyWriter.Close()

    resp, err := http.Post(targetUrl, contentType, bodyBuf)

    if err != nil {
        return err
    }
    defer resp.Body.Close()
    resp_body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        return err
    }
    fmt.Println(resp.Status)
    fmt.Println(string(resp_body))
    return nil
}

func postBigFile() error {
    //读文件
    path := "F:\\test\\hello.html"
    targetUrl := "http://localhost:9090/upload"

    bodyBuf := bytes.NewBufferString("")

    bodyWriter := multipart.NewWriter(bodyBuf)
    _, err := bodyWriter.CreateFormFile("userfile", path)
    if err != nil {
        fmt.Println("error writing to buffer")
        return err
    }

    file, err := os.Open(path)
    if err != nil {
        fmt.Println("error opening file")
        return err
    }
    defer file.Close()

    //大文件使用这个!!!
    boundary := bodyWriter.Boundary()
    closeString := fmt.Sprintf("\r\n--%s--\r\n", boundary)
    closeBuf := bytes.NewBufferString(closeString)
    rn := bytes.NewBufferString("\r\n")

    bodyBufField := new(bytes.Buffer)
    filedWrite := multipart.NewWriter(bodyBufField)
    filedWrite.SetBoundary(boundary)
    filedWrite.WriteField("xxxx", "yyyyyyyyyyy")

    requestReader := io.MultiReader(bodyBuf, file, rn, bodyBufField, closeBuf)

    contentType := bodyWriter.FormDataContentType()
    resp, err := http.Post(targetUrl, contentType, requestReader)
    if err != nil {
        return err
    }
    defer resp.Body.Close()
    respBody, err := ioutil.ReadAll(resp.Body)
    fmt.Println(string(respBody))
    if err != nil {
        return err
    }
    return nil
}