BoltOn.Web has a few filters and middlewares to be used in MVC/WebAPI applications.

In order to use the BoltOn.Web module, do the following:

• Install BoltOn.Web NuGet package.
• Call BoltOnWebModule() in your startup's BoltOn() method.
• Call TightenBolts() extenstion method for IApplicationBuilder.

Filters

• ModelValidationFilter
  It's a global filter which validates the models and throws BadRequestException with the validation error messages set in the DataAnnotation attributes.

• CustomExceptionFilter
  It's a global filter to handle all the exceptions thrown in the application and returns JSON with the CorrelationId as the Id, error message and with any of these HTTP response codes:

  • HTTP Response 400 - This is returned when a BadRequestException is thrown in the application, which usually happens for model validation errors. The ModelValidationFilter mentioned above throws this exception.
  • HTTP Response 412 - This is returned when a BusinessValidationException is thrown in the application, which is mainly used to display the actual business validation message to the user.
  • HTTP Response 500 - This status code is returned for all the unhandled exceptions with a generic error message or the actual exception message. The generic error message can be set in the appSettings with the key "ErrorMessage", and whether to return the actual exception message or a generic message can be controlled by a flag with the key "IsShowErrors" in the appSettings. It's recommended to enable IsShowErrors in the lower environments and disable it in the higher environments as the exception messages could have sensitive information.

The global filters can be registered like this in a WebAPI application:

services.AddControllers(c =>
{
    c.Filters.Add<CustomExceptionFilter>();
    c.Filters.Add<ModelValidationFilter>();
});

For MVC application, AddControllersWithViews method can be used.

Middlewares

• RequestLoggerContextMiddleware
  It's mainly used to add ClientIp, RequestUrl and CorrelationId to the LoggerContext, and it's automatically added when the BoltOn.Web is added.