http PUT 请求在 golang 中上传 zip 文件

Question

我的客户端代码基本上是尝试使用 HTTP PUT 方法将 tar.gz 文件上传到服务器。然而服务器似乎不喜欢它并且总是向我发送 500 ERROR 响应。以下是代码。我不确定出了什么问题。

 func upLoadFileToServer (uploadFileName string) {
    tr := &http.Transport{
          TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
          ExpectContinueTimeout : 30 * time.Second,
        }

    client := &http.Client{ Transport:tr,
                          Timeout: 20 * time.Second}

    timeCurrent = time.Now()
    fileContents, err := ioutil.ReadFile(uploadFileName)
    if err != nil {
     log.Println("Failed to Read the File", uploadFileName, err)
    }

    PutReq, _ := http.NewRequest("PUT", "https://www.example.com/upload", strings.NewReader(string(fileContents)))

    PutReq.Header.Set("Content-Type", "application/zip")
    PutReq.ContentLength = int64(len(string(fileContents)))


    PutReq.Header.Set("Expect", "100-continue")
    PutReq.Header.Set("Accept", "*/*")
    PutReq.Header.Set("Date", timeCurrent.Format(time.RFC1123))
    PutResp, err := client.Do(inventoryPutReq)
    }

有时我会注意到“Connection RESET by PEER”错误。但大多数时候它是 500。我使用 POSTMAN 尝试完全相同的请求，它似乎工作正常。

Answer 1

这是一个工作示例。

最有可能的情况是，服务器有点简单，并且按字面意思获取文件名。由于您没有在 uploadFileName 上使用 filepath.Base，因此它可能包含路径元素。只需在您的文件名上使用它即可进行测试。

重置可能是由超时引起的。

package main

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

var (
    targetPath string
    filename   string
    port       int
    handlerLog *log.Logger
    mainLog    *log.Logger
)

// This is automatically called after vars have been initialized and before main
func init() {
    flag.StringVar(&targetPath, "target", "./tmp", "target directory for uploads")
    flag.StringVar(&filename, "file", "", "file to upload")
    flag.IntVar(&port, "port", 0, "port to listen on. When 0, a random port is assigned")
    handlerLog = log.New(os.Stdout, "[handler] ", log.LstdFlags)
    mainLog = log.New(os.Stdout, "[main   ] ", log.LstdFlags)
}

// By returning a handler, we have an elegant way of initializing path.
func uploadHandler(path string) http.Handler {

    // We make sure path is an existing directory when the handler takes over
    if s, err := os.Stat(path); err != nil {
        if os.IsNotExist(err) {
            handlerLog.Printf("Target '%s' does not exist. Creating it...", path)
            if cerr := os.MkdirAll(path, 0755); cerr != nil {
                handlerLog.Fatalf("Creating target: %s", err)
            }
        } else {
            handlerLog.Fatalf("Error accessing '%s': %s", path, err)
        }
    } else if !s.IsDir() {
        handlerLog.Fatalf("Target '%s' is not a directory", path)
    }

    // Do NOT use this handler in production!!!
    // It is lacking all sorts of safety measures.
    // However, it is enough to demonstrate.
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        handlerLog.Println("Handling file upload...")

        handlerLog.Println("Parsing form...")
        if err := r.ParseMultipartForm(32 << 20); err != nil {
            handlerLog.Fatalf("Parsing form: %s", err)
        }
        f, h, err := r.FormFile("file")
        if err != nil {
            handlerLog.Printf("Error accessing file: %s", err)
            http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
            return
        }
        defer f.Close()

        handlerLog.Println("Opening output file...")
        t, err := os.OpenFile(filepath.Join(path, filepath.Base(h.Filename)), os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
        if err != nil {
            handlerLog.Printf("Opening output file: %s", err)
            http.Error(w, http.StatusText(http.StatusInternalServerError)+": "+err.Error(), http.StatusInternalServerError)
            return
        }
        defer t.Close()

        handlerLog.Println("Copying to output file...")
        if _, err = io.Copy(t, f); err != nil {
            handlerLog.Printf("Copying to output file: %s", err)

            http.Error(w, http.StatusText(http.StatusInternalServerError)+": "+err.Error(), http.StatusInternalServerError)
            return
        }
        handlerLog.Println("Finished handler!")
    })
}

func main() {
    flag.Parse()

    // Check input
    if filename == "" {
        mainLog.Fatal("No filename given. Exiting...")
    }

    mainLog.Println("Setting up upload handler...")
    http.Handle("/upload", uploadHandler(targetPath))

    wg := sync.WaitGroup{}
    wg.Add(1)

    // We want to finish the program after upload, as we only want to demonstrate
    go func() {
        mainLog.Println("Setting up listener...")

        listener, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", port))
        if err != nil {
            mainLog.Fatalf("%s", err)
        }
        defer listener.Close()

        port = listener.Addr().(*net.TCPAddr).Port
        mainLog.Printf("Listening to port %d on localhost", port)

        wg.Done()
        http.Serve(listener, nil)
    }()

    buf := bytes.NewBuffer(nil)
    bodyWriter := multipart.NewWriter(buf)

    // We need to truncate the input filename, as the server might be stupid and take the input
    // filename verbatim. Then, he will have directory parts which do not exist on the server.
    fileWriter, err := bodyWriter.CreateFormFile("file", filepath.Base(filename))
    if err != nil {
        mainLog.Fatalf("Creating fileWriter: %s", err)
    }

    file, err := os.Open(filename)
    if err != nil {
        mainLog.Fatalf("Opening file: %s", err)
    }
    defer file.Close()

    if _, err := io.Copy(fileWriter, file); err != nil {
        mainLog.Fatalf("Buffering file: %s", err)
    }

    // We have all the data written to the bodyWriter.
    // Now we can infer the content type
    contentType := bodyWriter.FormDataContentType()

    // This is mandatory as it flushes the buffer.
    bodyWriter.Close()

    // As we wait for the server to spin up, we need to wait here.
    mainLog.Println("Waiting for the listener to be set up...")
    wg.Wait()

    req, err := http.NewRequest(http.MethodPut, fmt.Sprintf("http://127.0.0.1:%d/upload", port), buf)
    if err != nil {
        mainLog.Fatalf("Creating request: %s", err)
    }
    req.Header.Set("Content-Type", contentType)

    client := http.Client{}

    mainLog.Println("Sending file")
    res, err := client.Do(req)
    if err != nil {
        mainLog.Fatalf("Sending file: %s", err)
    }

    mainLog.Printf("Received %s from server. Exiting...", res.Status)
}