Example of GlobalHttpExceptionFilter with BadRequest

GlobalHttpExceptionFilter.cs

public class GlobalHttpExceptionFilter : ExceptionFilterAttribute
{
    private readonly ILogger<GlobalHttpExceptionFilter> _exceptionLogger;
    private readonly Dictionary<Type, Action<ExceptionContext, Exception>> _exceptionHandlers;

    public GlobalHttpExceptionFilter(ILogger<GlobalHttpExceptionFilter> exceptionLogger)
    {
        _exceptionLogger = exceptionLogger ?? throw new ArgumentNullException(nameof(exceptionLogger));
        
        _exceptionHandlers = new Dictionary<Type, Action<ExceptionContext, Exception>>
        {
            { typeof(BadRequestException), HandleBadRequestException },
        };
    }

    public override void OnException(ExceptionContext context)
    {
        LogError(context);

        var exceptionType = context.Exception.GetType();
        if (_exceptionHandlers.ContainsKey(exceptionType))
        {
            _exceptionHandlers[exceptionType].Invoke(context, context.Exception);
        }
        else
        {
            HandleGenericException(context);
        }
    }

    private void LogError(ExceptionContext context)
    {
        _exceptionLogger.LogError(new EventId(context.Exception.HResult), context.Exception, context.Exception.Message);
    }

    private void HandleBadRequestException(ExceptionContext context, Exception exception)
    {
        var validationException = exception as BadRequestException;
        SetErrorResponse(context, StatusCodes.Status400BadRequest, "DomainValidations", validationException.Message);
    }

    private void HandleGenericException(ExceptionContext context)
    {
        SetErrorResponse(context, StatusCodes.Status500InternalServerError, "Message", context.Exception.Message);
    }

    private void SetErrorResponse(ExceptionContext context, int statusCode, string errorType, string errorMessage)
    {
        var problemDetails = BuildProblemDetails(context, statusCode, errorType, errorMessage);
        context.Result = statusCode == StatusCodes.Status400BadRequest 
            ? new BadRequestObjectResult(problemDetails) 
            : new ObjectResult(problemDetails) { StatusCode = statusCode };
        context.HttpContext.Response.StatusCode = statusCode;
    }

    private ValidationProblemDetails BuildProblemDetails(ExceptionContext context, int statusCode, string errorType, string errorMessage)
    {
        return new ValidationProblemDetails
        {
            Instance = context.HttpContext.Request.Path,
            Status = statusCode,
            Detail = "Please refer to the errors property for additional details.",
            Errors = { { errorType, new[] { errorMessage } } }
        };
    }
}