Why is catch block called twice in Grpc Interceptor C#?

Question

I ran into a problem when I started to implement a global error handler for the grpc server service. The problem is that when I get a validation error, I don't want to log it, but I want to return an RpcException with information to the client, and in other Exceptions I log it and return an unhandled error. The question is why do I repeatedly get into the catch block (Exception e) after I caught the ValidationException and threw the RpcException ? To the fact that it is called twice, the logic I described above breaks down for me. The implementation is shown below:

public class ExceptionInterceptor : Interceptor
{
    private readonly ILogger<ExceptionInterceptor> _logger;

    public ExceptionInterceptor(ILogger<ExceptionInterceptor> logger)
    {
        _logger = logger;
    }

    public override async Task<TResponse> UnaryServerHandler<TRequest, TResponse>(
        TRequest request,
        ServerCallContext context,
        UnaryServerMethod<TRequest, TResponse> continuation)
    {
        try
        {
            return await continuation(request, context);
        }
        catch (ValidationException e)
        {
            var error = string.Join(Environment.NewLine, e.Errors.Select(p => p.ErrorMessage));
            throw new RpcException(new Status(StatusCode.InvalidArgument, error));
        }
        catch (Exception e)
        {
            _logger.LogError(e, "gRPC Exception");
            throw;
        }
    }
}

Interceptor registration:

services.AddGrpc(o =>
{
    o.Interceptors.Add<ExceptionInterceptor>();
});

Answer 1

The reason was that when we register the interceptor globally, it fires twice. If we register it for a specific service, then it works once.The answer is:

services.AddGrpc()
    .AddServiceOptions<MyService>(o =>
    {
        o.Interceptors.Add<ExceptionInterceptor>();
    });