feat: add ability to do mutlipart ordered formdata along with file(s) #…

…669

middleware.go

@@ -399,6 +399,13 @@ func createMultipart(w *multipart.Writer, r *Request) error {
 	}
 
 	for _, mf := range r.multipartFields {
+		if len(mf.Values) > 0 {
+			for _, v := range mf.Values {
+				w.WriteField(mf.Name, v)
+			}
+			continue
+		}
+
 		if err := mf.openFileIfRequired(); err != nil {
 			return err
 		}

multipart.go

@@ -52,6 +52,11 @@ type MultipartField struct {
 	// ProgressCallback feature so that Resty sends the FileSize
 	// value via [MultipartFieldProgress]
 	ProgressCallback MultipartFieldCallbackFunc
+
+	// Values field is used to provide form field value. (Optional, unless it's a form-data field)
+	//
+	// It is primarily added for ordered multipart form-data field use cases
+	Values []string
 }
 
 // Clone method returns the deep copy of m except [io.Reader].

multipart_test.go

@@ -426,6 +426,66 @@ func TestMultipartFieldProgressCallback(t *testing.T) {
 	assertEqual(t, true, strings.Contains(responseStr, "100mbfile.bin"))
 }
 
+func TestMultipartOrderedFormData(t *testing.T) {
+	ts := createFormPostServer(t)
+	defer ts.Close()
+	defer cleanupFiles(".testdata/upload")
+
+	jsonStr1 := `{"input": {"name": "Uploaded document 1", "_filename" : ["file1.txt"]}}`
+	jsonStr2 := `{"input": {"name": "Uploaded document 2", "_filename" : ["file2.txt"]}}`
+
+	fields := []*MultipartField{
+		{
+			Name:   "field1",
+			Values: []string{"field1value1", "field1value2"},
+		},
+		{
+			Name:   "field2",
+			Values: []string{"field2value1", "field2value2"},
+		},
+		{
+			Name:        "uploadManifest1",
+			FileName:    "upload-file-1.json",
+			ContentType: "application/json",
+			Reader:      bytes.NewBufferString(jsonStr1),
+		},
+		{
+			Name:   "field3",
+			Values: []string{"field3value1", "field3value2"},
+		},
+		{
+			Name:        "uploadManifest2",
+			FileName:    "upload-file-2.json",
+			ContentType: "application/json",
+			Reader:      bytes.NewBufferString(jsonStr2),
+		},
+		{
+			Name:   "field4",
+			Values: []string{"field4value1", "field4value2"},
+		},
+		{
+			Name:        "uploadManifest3",
+			ContentType: "application/json",
+			Reader:      bytes.NewBufferString(jsonStr2),
+		},
+	}
+
+	c := dcnld().SetBaseURL(ts.URL)
+
+	resp, err := c.R().
+		SetMultipartOrderedFormData("first_name", []string{"Jeevanandam"}).
+		SetMultipartOrderedFormData("last_name", []string{"M"}).
+		SetMultipartFields(fields...).
+		Post("/upload")
+
+	responseStr := resp.String()
+
+	assertError(t, err)
+	assertEqual(t, http.StatusOK, resp.StatusCode())
+	assertEqual(t, true, strings.Contains(responseStr, "upload-file-1.json"))
+	assertEqual(t, true, strings.Contains(responseStr, "upload-file-2.json"))
+}
+
 var errTestErrorReader = errors.New("fake")
 
 type errorReader struct{}
@@ -484,7 +544,7 @@ func (mwe *mpWriterError) Write(p []byte) (int, error) {
 	return 0, errors.New("multipart write error")
 }
 
-func TestMulipartRequest_createMultipart(t *testing.T) {
+func TestMultipartRequest_createMultipart(t *testing.T) {
 	mw := multipart.NewWriter(&mpWriterError{})
 
 	c := dcnl()

request.go

@@ -507,6 +507,17 @@ func (r *Request) SetMultipartFormData(data map[string]string) *Request {
 	return r
 }
 
+// SetMultipartOrderedFormData method allows add ordered form data to be attached to the request
+// as `multipart:form-data`
+func (r *Request) SetMultipartOrderedFormData(name string, values []string) *Request {
+	r.isMultiPart = true
+	r.multipartFields = append(r.multipartFields, &MultipartField{
+		Name:   name,
+		Values: values,
+	})
+	return r
+}
+
 // SetMultipartField method sets custom data with Content-Type using [io.Reader] for multipart upload.
 //
 // Resty provides an optional multipart live upload progress callback;

resty_test.go

@@ -387,6 +387,9 @@ func createFormPostServer(t *testing.T) *httptest.Server {
 				targetPath := filepath.Join(getTestDataPath(), "upload")
 				_ = os.MkdirAll(targetPath, 0700)
 
+				values := r.MultipartForm.Value
+				t.Logf("%v", values)
+
 				for _, fhdrs := range r.MultipartForm.File {
 					for _, hdr := range fhdrs {
 						t.Logf("Name: %v", hdr.Filename)