[CLD-7029] Add a new system console page for configuring custom export FileSettings (#26034)

* Add a new system console page for configuring custom export FileSettings

* Remove NONE option for ExportDriverName dropdown

* Fix tests

* Fix i18n

* Update webapp/channels/src/components/admin_console/admin_definition.tsx

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

* PR Feedback

* Fix formatting

* gofmt

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/channels/app/file.go

@@ -57,7 +57,13 @@ func (a *App) ExportFileBackend() filestore.FileBackend {
 }
 
 func (a *App) CheckMandatoryS3Fields(settings *model.FileSettings) *model.AppError {
-	fileBackendSettings := filestore.NewFileBackendSettingsFromConfig(settings, false, false)
+	var fileBackendSettings filestore.FileBackendSettings
+	if a.License().IsCloud() && a.Config().FeatureFlags.CloudDedicatedExportUI && a.Config().FileSettings.DedicatedExportStore != nil && *a.Config().FileSettings.DedicatedExportStore {
+		fileBackendSettings = filestore.NewExportFileBackendSettingsFromConfig(settings, false, false)
+	} else {
+		fileBackendSettings = filestore.NewFileBackendSettingsFromConfig(settings, false, false)
+	}
+
 	err := fileBackendSettings.CheckMandatoryS3Fields()
 	if err != nil {
 		return model.NewAppError("CheckMandatoryS3Fields", "api.admin.test_s3.missing_s3_bucket", nil, "", http.StatusBadRequest).Wrap(err)
@@ -87,7 +93,15 @@ func (a *App) TestFileStoreConnection() *model.AppError {
 func (a *App) TestFileStoreConnectionWithConfig(cfg *model.FileSettings) *model.AppError {
 	license := a.Srv().License()
 	insecure := a.Config().ServiceSettings.EnableInsecureOutgoingConnections
-	backend, err := filestore.NewFileBackend(filestore.NewFileBackendSettingsFromConfig(cfg, license != nil && *license.Features.Compliance, insecure != nil && *insecure))
+	var backend filestore.FileBackend
+	var err error
+	complianceEnabled := license != nil && *license.Features.Compliance
+	if license.IsCloud() && a.Config().FeatureFlags.CloudDedicatedExportUI && a.Config().FileSettings.DedicatedExportStore != nil && *a.Config().FileSettings.DedicatedExportStore {
+		allowInsecure := a.Config().ServiceSettings.EnableInsecureOutgoingConnections != nil && *a.Config().ServiceSettings.EnableInsecureOutgoingConnections
+		backend, err = filestore.NewFileBackend(filestore.NewExportFileBackendSettingsFromConfig(cfg, complianceEnabled && license.IsCloud(), allowInsecure))
+	} else {
+		backend, err = filestore.NewFileBackend(filestore.NewFileBackendSettingsFromConfig(cfg, complianceEnabled, insecure != nil && *insecure))
+	}
 	if err != nil {
 		return model.NewAppError("FileBackend", "api.file.no_driver.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
 	}