Tweak PR a bit

By using `query.Values` we are using the URL tags and are omitting any
empty values. This seems to be inline with what the API expects. Could
you both this this version @dheitman42 and @zbindenren?

group_import_export.go

@@ -96,13 +96,13 @@ type GroupImportFileOptions struct {
 // https://docs.gitlab.com/ce/api/group_import_export.html#import-a-file
 func (s *GroupImportExportService) ImportFile(opt *GroupImportFileOptions, options ...RequestOptionFunc) (*Response, error) {
 	// First check if we got all required options.
-	if opt.Name == nil || *opt.Name == "" {
+	if opt == nil || opt.Name == nil || *opt.Name == "" {
 		return nil, fmt.Errorf("Missing required option: Name")
 	}
-	if opt.Path == nil || *opt.Path == "" {
+	if opt == nil || opt.Path == nil || *opt.Path == "" {
 		return nil, fmt.Errorf("Missing required option: Path")
 	}
-	if opt.File == nil || *opt.File == "" {
+	if opt == nil || opt.File == nil || *opt.File == "" {
 		return nil, fmt.Errorf("Missing required option: File")
 	}
 

project_import_export.go

@@ -18,14 +18,14 @@ package gitlab
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"io"
 	"mime/multipart"
 	"net/http"
 	"os"
-	"strings"
 	"time"
+
+	"github.com/google/go-querystring/query"
 )
 
 // ProjectImportExportService handles communication with the project
@@ -179,41 +179,54 @@ type ImportFileOptions struct {
 // GitLab API docs:
 // https://docs.gitlab.com/ce/api/project_import_export.html#import-a-file
 func (s *ProjectImportExportService) ImportFile(opt *ImportFileOptions, options ...RequestOptionFunc) (*ImportStatus, *Response, error) {
+	// First check if we got all required options.
+	if opt == nil || opt.File == nil || *opt.File == "" {
+		return nil, nil, fmt.Errorf("Missing required option: File")
+	}
+	if opt == nil || opt.Path == nil || *opt.Path == "" {
+		return nil, nil, fmt.Errorf("Missing required option: Path")
+	}
+
 	file, err := os.Open(*opt.File)
 	if err != nil {
 		return nil, nil, err
 	}
 	defer file.Close()
-	var b bytes.Buffer
-	writer := multipart.NewWriter(&b)
-	var optMap map[string]interface{}
-	optMarshalled, err := json.Marshal(opt)
+
+	b := &bytes.Buffer{}
+	w := multipart.NewWriter(b)
+
+	fields, err := query.Values(opt)
 	if err != nil {
 		return nil, nil, err
 	}
-	json.Unmarshal(optMarshalled, &optMap)
 
-	for key, value := range optMap {
-		if strings.ToLower(key) == "file" {
-			part, err := writer.CreateFormFile("file", file.Name())
+	for name := range fields {
+		if name == "file" {
+			part, err := w.CreateFormFile("file", file.Name())
 			if err != nil {
 				return nil, nil, err
 			}
-			_, err = io.Copy(part, file)
+			if _, err = io.Copy(part, file); err != nil {
+				return nil, nil, err
+			}
 		} else {
-			_ = writer.WriteField(strings.ToLower(key), fmt.Sprintf("%v", value))
+			if err = w.WriteField(name, fmt.Sprintf("%v", fields.Get(name))); err != nil {
+				return nil, nil, err
+			}
 		}
 	}
 
-	err = writer.Close()
+	err = w.Close()
 	if err != nil {
 		return nil, nil, err
 	}
-	req, err := s.client.NewRequest(http.MethodPost, "projects/import", &b, options)
+
+	req, err := s.client.NewRequest(http.MethodPost, "projects/import", b, options)
 	if err != nil {
 		return nil, nil, err
 	}
-	req.Header.Set("Content-Type", writer.FormDataContentType())
+	req.Header.Set("Content-Type", w.FormDataContentType())
 
 	is := new(ImportStatus)
 	resp, err := s.client.Do(req, is)

project_import_export_test.go

@@ -128,63 +128,6 @@ func TestProjectImportExportService_ExportDownload(t *testing.T) {
 	require.Equal(t, http.StatusNotFound, resp.StatusCode)
 }
 
-func TestProjectImportExportService_ImportFile(t *testing.T) {
-	mux, server, client := setup(t)
-	defer teardown(server)
-
-	mux.HandleFunc("/api/v4/projects/import", func(w http.ResponseWriter, r *http.Request) {
-		testMethod(t, r, http.MethodPost)
-		fmt.Fprintf(w, `
-			{
-			  "id": 1,
-			  "description": null,
-			  "name": "api-project",
-			  "name_with_namespace": "Administrator / api-project",
-			  "path": "api-project",
-			  "path_with_namespace": "root/api-project",
-			  "import_status": "scheduled",
-			  "correlation_id": "mezklWso3Za",
-			  "failed_relations": []
-			}
-		`)
-	})
-
-	want := &ImportStatus{
-		ID:                1,
-		Description:       "",
-		Name:              "api-project",
-		NameWithNamespace: "Administrator / api-project",
-		Path:              "api-project",
-		PathWithNamespace: "root/api-project",
-		ImportStatus:      "scheduled",
-	}
-
-	es, resp, err := client.ProjectImportExport.ImportFile(nil, nil)
-	require.NoError(t, err)
-	require.NotNil(t, resp)
-	require.Equal(t, want, es)
-
-	es, resp, err = client.ProjectImportExport.ImportFile(nil, errorOption)
-	require.EqualError(t, err, "RequestOptionFunc returns an error")
-	require.Nil(t, resp)
-	require.Nil(t, es)
-}
-
-func TestProjectImportExportService_ImportFile_NotFound(t *testing.T) {
-	mux, server, client := setup(t)
-	defer teardown(server)
-
-	mux.HandleFunc("/api/v4/projects/import", func(w http.ResponseWriter, r *http.Request) {
-		testMethod(t, r, http.MethodPost)
-		w.WriteHeader(http.StatusNotFound)
-	})
-
-	es, resp, err := client.ProjectImportExport.ImportFile(nil, nil)
-	require.Error(t, err)
-	require.Nil(t, es)
-	require.Equal(t, http.StatusNotFound, resp.StatusCode)
-}
-
 func TestProjectImportExportService_ImportStatus(t *testing.T) {
 	mux, server, client := setup(t)
 	defer teardown(server)