vendor: add github.com/koofr/go-koofrclient

* added koofr client SDK dep for koofr backend

vendor/github.com/koofr/go-httpclient/requestdata_upload.go

@@ -0,0 +1,62 @@
+package httpclient
+
+import (
+	"io"
+	"mime/multipart"
+	"net/http"
+)
+
+func (req *RequestData) UploadFile(fieldName string, fileName string, reader io.Reader) (err error) {
+	return req.UploadFileExtra(fieldName, fileName, reader, nil)
+}
+
+func (req *RequestData) UploadFileExtra(fieldName string, fileName string, reader io.Reader, extra map[string]string) (err error) {
+	r, w := io.Pipe()
+
+	writer := multipart.NewWriter(w)
+
+	go func() {
+		var err error
+
+		defer func() {
+			if err == nil {
+				w.Close()
+			}
+		}()
+
+		for k, v := range extra {
+			err = writer.WriteField(k, v)
+
+			if err != nil {
+				w.CloseWithError(err)
+				return
+			}
+		}
+
+		part, err := writer.CreateFormFile(fieldName, fileName)
+
+		if err != nil {
+			w.CloseWithError(err)
+			return
+		}
+
+		defer writer.Close()
+
+		_, err = io.Copy(part, reader)
+
+		if err != nil {
+			w.CloseWithError(err)
+			return
+		}
+	}()
+
+	req.ReqReader = r
+
+	if req.Headers == nil {
+		req.Headers = make(http.Header)
+	}
+
+	req.Headers.Set("Content-Type", writer.FormDataContentType())
+
+	return
+}