Question

我正在尝试找出如何使用golang从mailgun接收电子邮件的文件附件。它们仅提供python示例https://documentation.mailgun.com/en/latest/quickstart-receiving.html：

# Handler for HTTP POST to http://myhost.com/messages for the route defined above
def on_incoming_message(request):
     if request.method == 'POST':
         sender    = request.POST.get('sender')
         recipient = request.POST.get('recipient')
         subject   = request.POST.get('subject', '')

         body_plain = request.POST.get('body-plain', '')
         body_without_quotes = request.POST.get('stripped-text', '')
         # note: other MIME headers are also posted here...

         # attachments:
         for key in request.FILES:
             file = request.FILES[key]
             # do something with the file

     # Returned text is ignored but HTTP status code matters:
     # Mailgun wants to see 2xx, otherwise it will make another attempt in 5 minutes
     return HttpResponse('OK')

我应该如何在Go中处理此部分，或者“文件”是什么类型？

# attachments:
         for key in request.FILES:
             file = request.FILES[key]

Answer 1

您可以让Mailgun在您的域的路由设置中发送对回调的样本请求：https://app.mailgun.com/app/routes。要快速浏览，请在http://bin.mailgun.net上创建一个bin，然后输入该URL。

您将看到对“转发”操作的请求包含multipart / form-data主体，因此您使用http.Request.FormFile访问附件：

http.HandleFunc("/callback", func(w http.ResponseWriter, r *http.Request) {
    // r.FormFile and r.FormValue will call ParseMultipartForm
    // automatically if necessary, but they ignore any errors. For
    // robustness we do it ourselves.
    if err := r.ParseMultipartForm(10 << 20); err != nil {
        http.Error(w, err.Error(), 500)
        return
    }

    // The "attachment-count" field reports how many attachments there are.
    n, _ := strconv.Atoi(r.FormValue("attachment-count"))

    // The file fields are then named "attachment-1", "attachment-2", ..., "attachment-n".
    for i := 1; i <= n; i++ {
        fieldName := fmt.Sprintf("attachment-%d", i)
        file, header, err := r.FormFile(fieldName)
        if err != nil {
            http.Error(w, err.Error(), 500)
            return
        }

        fmt.Printf("%s (%d bytes)\n", header.Filename, header.Size)

        var _ = file // call file.Read() to read the file contents
    }
})

对于Mailgun的测试有效负载，输出为：

crabby.gif (2785 bytes)
attached_файл.txt (32 bytes)

如何在Go中从Mailgun接收文件附件

1 个答案: