[MM-42022] Don't break importing process on missing display name of a channel (#19641)

* Don't break importing process on missing display name of a channel

* remove unused strings

Co-authored-by: = <=>

app/import_validators.go

@@ -165,9 +165,9 @@ func validateChannelImportData(data *ChannelImportData) *model.AppError {
 		return model.NewAppError("BulkImport", "app.import.validate_channel_import_data.name_characters.error", nil, "", http.StatusBadRequest)
 	}
 
-	if data.DisplayName == nil {
-		return model.NewAppError("BulkImport", "app.import.validate_channel_import_data.display_name_missing.error", nil, "", http.StatusBadRequest)
-	} else if utf8.RuneCountInString(*data.DisplayName) == 0 || utf8.RuneCountInString(*data.DisplayName) > model.ChannelDisplayNameMaxRunes {
+	if data.DisplayName == nil || utf8.RuneCountInString(*data.DisplayName) == 0 {
+		data.DisplayName = data.Name // when displayName is missing we use name instead for displaying so we might as well convert it here.
+	} else if utf8.RuneCountInString(*data.DisplayName) > model.ChannelDisplayNameMaxRunes {
 		return model.NewAppError("BulkImport", "app.import.validate_channel_import_data.display_name_length.error", nil, "", http.StatusBadRequest)
 	}
 

app/import_validators_test.go

@@ -404,11 +404,13 @@ func TestImportValidateChannelImportData(t *testing.T) {
 		Type: &chanTypeOpen,
 	}
 	err = validateChannelImportData(&data)
-	require.NotNil(t, err, "Should have failed due to missing display_name.")
+	require.Nil(t, err, "Should have accepted having an empty display_name.")
+	require.Equal(t, data.Name, data.DisplayName, "Name and DisplayName should be the same if DisplayName is missing")
 
 	data.DisplayName = ptrStr("")
 	err = validateChannelImportData(&data)
-	require.NotNil(t, err, "Should have failed due to empty display_name.")
+	require.Nil(t, err, "Should have accepted having an empty display_name.")
+	require.Equal(t, data.Name, data.DisplayName, "Name and DisplayName should be the same if DisplayName is missing")
 
 	data.DisplayName = ptrStr(strings.Repeat("abcdefghij", 7))
 	err = validateChannelImportData(&data)

i18n/en.json

@@ -5123,10 +5123,6 @@
     "id": "app.import.validate_channel_import_data.display_name_length.error",
     "translation": "Channel display_name is not within permitted length constraints."
   },
-  {
-    "id": "app.import.validate_channel_import_data.display_name_missing.error",
-    "translation": "Missing required channel property: display_name"
-  },
   {
     "id": "app.import.validate_channel_import_data.header_length.error",
     "translation": "Channel header is too long."