how to binding for multi files upload

[wuhuizuo]

#1263's merged solution take no effect for multi files uploading.

my code:

// MailUpload struct for e-mail
type MailUpload struct {
	Mail string 			     `json:"mail" form:"mail" binding:"required"`
	Attachments  []*multipart.FileHeader `json:"attachment,omitempty" form:"attachments" binding:"required"` // change form to "attachments[]" take no effect also.
}

func Mail(c *gin.Context) {
	var postData MailUpload
	err := c.Bind(&postData)
	if err != nil {
		fmt.Println(err)
		c.String(http.StatusBadRequest, err.Error())
	} else {
		fmt.Printf("%#v\n", postData)
		c.String(http.StatusOK, "ok")
	}
}

request send command by curl:

curl -v -H "Content-Type:multipart/form-data" -X POST http://localhost:8080/api/latest/newmail -F "attachments[]=@./2019-5-1_day_trends.png" -F mail=123

my error: Key: 'MailUpload.Attachments' Error:Field validation for 'Attachments' failed on the 'required' tag

[yyq2013]

I have same issues, my form has two file fields, and one of it is file array, like following:

bindform

type UserProfileForm struct {
	OtherImages []*multipart.FileHeader `form:"images" binding:"-"`
	Avatar      *multipart.FileHeader `form:"avatar" binding:"-"`
	User        string                `form:"user" binding:"required"`
}

it only works as following:

bindForm

   type UserProfileForm struct {
	OtherImages *multipart.FileHeader `form:"images" binding:"-"`
	Avatar      *multipart.FileHeader `form:"avatar" binding:"-"`
	User        string                `form:"user" binding:"required"`
}

as a workaround, just get file array like this:

workround code

bindForm := UserProfileForm{}
if err := c.ShouldBind(&bindForm); err != nil {
	c.JSON(http.StatusBadRequest, gin.H{"message": "Bad form data found"})
	return
}
    mForm, _ := c.MultipartForm()
images := mForm.File["images"]
    bindForm.OtherImages = images

Wish gin can fix it.

[thinkerou]

when we need to use []*multipart.FileHeader?
I use postman, how upload multi file once?
so, when you want to multi file, maybe you may use:

type Test struct {
  File1 *multipart.FileHeader `form: "file1" binding:"required"`
  File2 *multipart.FileHeader `form: "file2" binding:"required"`
}

[wuhuizuo]

when we need to use []*multipart.FileHeader?
I use postman, how upload multi file once?
so, when you want to multi file, maybe you may use:

type Test struct {
  File1 *multipart.FileHeader `form: "file1" binding:"required"`
  File2 *multipart.FileHeader `form: "file2" binding:"required"`
}

limit the file form key name is not a good idea。if you declare only file1 and file2, how to deal file3, file4 ?

[thinkerou]

@wuhuizuo I known, []*multipart.FileHeader should also support. only curiosity what about scn.

[amirex128]

type CreateProduct struct {
	Images           []*multipart.FileHeader `form:"images[]"`
}

You must use something. Like that

[dsp1589]

I have same issues, my form has two file fields, and one of it is file array, like following:

bindform

type UserProfileForm struct {
	OtherImages []*multipart.FileHeader `form:"images" binding:"-"`
	Avatar      *multipart.FileHeader `form:"avatar" binding:"-"`
	User        string                `form:"user" binding:"required"`
}

it only works as following:

bindForm

   type UserProfileForm struct {
	OtherImages *multipart.FileHeader `form:"images" binding:"-"`
	Avatar      *multipart.FileHeader `form:"avatar" binding:"-"`
	User        string                `form:"user" binding:"required"`
}

as a workaround, just get file array like this:

workround code

bindForm := UserProfileForm{}
if err := c.ShouldBind(&bindForm); err != nil {
	c.JSON(http.StatusBadRequest, gin.H{"message": "Bad form data found"})
	return
}
    mForm, _ := c.MultipartForm()
images := mForm.File["images"]
    bindForm.OtherImages = images

Wish gin can fix it.

Why it should be "-" for binding? cant we use "required" for files?

[kwamekyeimonies]

how do I read in this case :type MasterTemplate struct {
ID uuid.UUID form:"id" json:"id"
IsVoice bool form:"is_voice" json:"is_voice"
Title string form:"title" json:"title"
IsSms bool form:"is_sms" json:"is_sms"
FilePath string form:"file_path" json:"file_path"
Content []struct {
File *multipart.FileHeader form:"file" json:"file"
MsgTmplateLangId string form:"msg_template_lang_id" json:"msg_template_lang_id"
SMSContent string form:"sms_content" json:"sms_content"
MsgContentID string form:"msg_content_id" json:"msg_content_id"
} form:"content" json:"content"
UserID uuid.UUID form:"user_id" json:"user_id"
}