1. @override
Future<int> handle()

Handles the command input.

Override this method to perform actions for this command.

Return value is the value returned to the command line operation. Return 0 for success.

Source 

@override
Future<int> handle() async {
  if (clientID == null) {
    displayError("Option --id required.");
    return 1;
  }
  if ((scopes?.isEmpty ?? true)) {
    displayError("Option --scopes required.");
    return 1;
  }

  var dataModel = new ManagedDataModel.fromCurrentMirrorSystem();
  ManagedContext.defaultContext = new ManagedContext.standalone(dataModel, persistentStore);

  var scopingClient = new AuthClient.public(
      clientID, allowedScopes: scopes?.map((s) => new AuthScope(s))?.toList());

  var query = new Query<ManagedClient>()
    ..where.id = whereEqualTo(clientID)
    ..values.allowedScope = scopingClient.allowedScopes?.map((s) => s.scopeString)?.join(" ");


  try {
    var result = await query.updateOne();
    if (result == null) {
      displayError("Client ID '$clientID' does not exist.");
      return 1;
    }

    displayInfo("Success", color: CLIColor.green);
    displayProgress("Client with ID '$clientID' has been updated.");
    displayProgress("Updated scope: ${result.allowedScope}");
    return 0;
  } on QueryException catch (e) {
    displayError("Updating Client Scope Failed");

    displayProgress("$e");
  }

  return 1;
}