Bug: Adding users is not possible

[berrnd]

Originally reported at: https://www.reddit.com/r/grocy/comments/1979qpn

User management support in Grocy Desktop was added in Grocy Desktop v2.6.0 / Grocy v4.0.2 (ref #47 and grocy/grocy@dedbee3).

However, currently it seems to be broken:

Everytime I try to add a user the screen just flashes but nothing happens.

Underlying error (500 for POST http://localhost:4010/api/users):

{
    "error_message": "Grocy\\Services\\UsersService::CreateUser(): Argument #4 ($password) must be of type string, null given, called in C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\controllers\\UsersApiController.php on line 46",
    "error_details": {
        "stack_trace": "#0 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\controllers\\UsersApiController.php(46): Grocy\\Services\\UsersService->CreateUser()\n#1 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Handlers\\Strategies\\RequestResponse.php(38): Grocy\\Controllers\\UsersApiController->CreateUser()\n#2 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Routing\\Route.php(358): Slim\\Handlers\\Strategies\\RequestResponse->__invoke()\n#3 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(65): Slim\\Routing\\Route->handle()\n#4 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\middleware\\JsonMiddleware.php(13): Slim\\MiddlewareDispatcher->handle()\n#5 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(168): Grocy\\Middleware\\JsonMiddleware->__invoke()\n#6 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(65): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#7 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Routing\\Route.php(315): Slim\\MiddlewareDispatcher->handle()\n#8 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Routing\\RouteRunner.php(68): Slim\\Routing\\Route->run()\n#9 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\middleware\\LocaleMiddleware.php(16): Slim\\Routing\\RouteRunner->handle()\n#10 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(269): Grocy\\Middleware\\LocaleMiddleware->__invoke()\n#11 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\middleware\\AuthMiddleware.php(49): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#12 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(269): Grocy\\Middleware\\AuthMiddleware->__invoke()\n#13 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Middleware\\RoutingMiddleware.php(45): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#14 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(121): Slim\\Middleware\\RoutingMiddleware->process()\n#15 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\Middleware\\ErrorMiddleware.php(76): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#16 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(121): Slim\\Middleware\\ErrorMiddleware->process()\n#17 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\middleware\\CorsMiddleware.php(27): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#18 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(269): Grocy\\Middleware\\CorsMiddleware->__invoke()\n#19 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\MiddlewareDispatcher.php(65): Psr\\Http\\Server\\RequestHandlerInterface@anonymous->handle()\n#20 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\App.php(199): Slim\\MiddlewareDispatcher->handle()\n#21 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\packages\\slim\\slim\\Slim\\App.php(183): Slim\\App->handle()\n#22 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\app.php(112): Slim\\App->run()\n#23 C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\public\\index.php(45): require_once('...')\n#24 {main}",
        "file": "C:\\Users\\bb\\AppData\\Roaming\\grocy-desktop\\runtime-dependencies\\2.7.0\\grocy\\services\\UsersService.php",
        "line": 9
    }
}