[MM-31247] Add support for compressed export files with attachments (#16614)

* Include filepaths for post attachments

* Cleanup

* Enable exporting file attachments

* Fix file import

* Enable zip export

* Support creating missing directories when unzipping

* Add test

* Add translations

* Export direct channel posts attachments

* Fix returned values order

Remove pointer to slice in return

* [MM-31597] Implement export process job (#16626)

* Implement export process job

* Add translations

* Remove unused value

* [MM-31249] Add /exports API endpoint (#16633)

* Implement API endpoints to list, download and delete export files

* Add endpoint for single resource

* Update i18n/en.json

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

* Update i18n/en.json

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

* Fix var name

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

app/import_functions.go

@@ -9,7 +9,7 @@ import (
 	"crypto/sha1"
 	"errors"
 	"fmt"
-	"io"
+	"io/ioutil"
 	"net/http"
 	"os"
 	"path"
@@ -1117,10 +1117,15 @@ func (a *App) importAttachment(data *AttachmentImportData, post *model.Post, tea
 	if file == nil || err != nil {
 		return nil, model.NewAppError("BulkImport", "app.import.attachment.bad_file.error", map[string]interface{}{"FilePath": *data.Path}, "", http.StatusBadRequest)
 	}
+	defer file.Close()
 
 	timestamp := utils.TimeFromMillis(post.CreateAt)
-	buf := bytes.NewBuffer(nil)
-	_, _ = io.Copy(buf, file)
+
+	fileData, err := ioutil.ReadAll(file)
+	if err != nil {
+		return nil, model.NewAppError("BulkImport", "app.import.attachment.read_file_data.error", map[string]interface{}{"FilePath": *data.Path}, "", http.StatusBadRequest)
+	}
+
 	// Go over existing files in the post and see if there already exists a file with the same name, size and hash. If so - skip it
 	if post.Id != "" {
 		oldFiles, err := a.GetFileInfosForPost(post.Id, true)
@@ -1128,11 +1133,11 @@ func (a *App) importAttachment(data *AttachmentImportData, post *model.Post, tea
 			return nil, model.NewAppError("BulkImport", "app.import.attachment.file_upload.error", map[string]interface{}{"FilePath": *data.Path}, "", http.StatusBadRequest)
 		}
 		for _, oldFile := range oldFiles {
-			if oldFile.Name != path.Base(file.Name()) || oldFile.Size != int64(buf.Len()) {
+			if oldFile.Name != path.Base(file.Name()) || oldFile.Size != int64(len(fileData)) {
 				continue
 			}
 			// check md5
-			newHash := sha1.Sum(buf.Bytes())
+			newHash := sha1.Sum(fileData)
 			oldFileData, err := a.GetFile(oldFile.Id)
 			if err != nil {
 				return nil, model.NewAppError("BulkImport", "app.import.attachment.file_upload.error", map[string]interface{}{"FilePath": *data.Path}, "", http.StatusBadRequest)
@@ -1145,15 +1150,19 @@ func (a *App) importAttachment(data *AttachmentImportData, post *model.Post, tea
 			}
 		}
 	}
-	fileInfo, appErr := a.DoUploadFile(timestamp, teamID, post.ChannelId, post.UserId, file.Name(), buf.Bytes())
+
+	mlog.Info("Uploading file with name", mlog.String("file_name", file.Name()))
+
+	fileInfo, appErr := a.DoUploadFile(timestamp, teamID, post.ChannelId, post.UserId, file.Name(), fileData)
 	if appErr != nil {
 		mlog.Error("Failed to upload file:", mlog.Err(appErr))
 		return nil, appErr
 	}
 
-	a.HandleImages([]string{fileInfo.PreviewPath}, []string{fileInfo.ThumbnailPath}, [][]byte{buf.Bytes()})
+	if fileInfo.IsImage() {
+		a.HandleImages([]string{fileInfo.PreviewPath}, []string{fileInfo.ThumbnailPath}, [][]byte{fileData})
+	}
 
-	mlog.Info("Uploading file with name", mlog.String("file_name", file.Name()))
 	return fileInfo, nil
 }