package api

import (
    "os"
    "bytes"
    "mime/multipart"
    "path/filepath"
    "io"
    "net/http"
    "errors"
    "fmt"
    "io/ioutil"
)
//上传文件到指定的位置
func Upload(host string, port int, vid uint64, fid uint64, filePath string, fileName string) (err error) {
    if fileName == "" {
        fileName = filepath.Base(filePath)
    }

    url := fmt.Sprintf("http://%s:%d/%d/%d/%s", host, port, vid, fid, fileName)
    file, err := os.Open(filePath)
    if os.IsNotExist(err) {
        return
    }

    body := new(bytes.Buffer)
    mPart := multipart.NewWriter(body)

    filePart, err := mPart.CreateFormFile("file", fileName)
    if err != nil {
        return
    }

    _, err = io.Copy(filePart, file)
    if err != nil {
        return
    }

    mPart.Close()

    req, err := http.NewRequest(http.MethodPost, url, body)
    if err != nil {
        return
    }
    req.Header.Set("Content-Type", mPart.FormDataContentType())

    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        return
    }
    defer resp.Body.Close()

    if resp.StatusCode != http.StatusCreated {
        body, _ := ioutil.ReadAll(resp.Body)
        err = errors.New(fmt.Sprintf("%d != http.StatusCreated  body: %s", resp.StatusCode, body))
    }
    return
}