dotnet

Another day, another unexpected problem. Launching a .NET 8 app from a docker container, I got this error: Failed to create CoreCLR, HRESULT: 0x80070008. I was puzzled as the same container ran smoothly in our test environment but not in production. I ruled out resource problems (memory or disk full, maybe?) but then compared the Docker Engine versions we run in test and production. Both were old (20. xx when 25 is available), but interestingly, the production version was older....

Today’s fun was implementing OAuth2’s RFC 7636’s PKCE (Proof Key for Code Exchange) in C#. It’s relatively straightforward, but I decided to share my implementation should it be helpful to someone else out there. PKCE is an extension to the Authorization Code flow to prevent CSRF and authorization code injection attacks. [..] It was originally designed to protect the authorization code flow in mobile apps, but its ability to prevent authorization code injection makes it useful for every type of OAuth client, even web apps that use client authentication (source)....

Today I released Fattura Elettronica for .NET v3.4.13. The Fattura Elettronica project allows for the validation and de/serialization of electronic invoices that adhere to the standard defined by Italian Revenue Agency (Agenzia Entrate). See the changelog for details (Italian).

In a few days, on Monday, December 4, at 10 a.m., I will present at the .NET Conference Italia 2023, which will be held at the Microsoft House in Milan. My session is titled “C#12 What’s new and interesting” and is part of a rich agenda focused on the recent release of .NET 8. I presented on the same subject at a DevRomagna meetup a few months ago when C# 12 was in preview and still had several moving parts....

Today, I (re)learned how to serialize an XML to a UTF-8 string. Like all the other times I did this, I got backstabbed by StringWriter, which only supports UTF-16. A simple code snippet like this: await using var sw = new StringWriter(); await using var w = XmlWriter.Create(sw, new() { Async = true }); ... await w.FlushAsync(); return sw.ToString(); Will emit this output: <?xml version="1.0" encoding="utf-16"?><... There’s nothing inherently wrong with UTF-16, but XML is usually UTF-8, so one must do something about it....

Fattura Elettronica for .NET v3.4.11 was released on NuGet today. The Fattura Elettronica project allows for the fixes a missing validation point. See the changelog for details (Italian). validation and de/serialization of electronic invoices following the Italian Revenue Agency standards.

Today I learned how to implement a custom Enumerable.DistinctBy extension method that returns distinct elements from a sequence according to a specified key selector function. .NET 6 and its successors have the method built in within LINQ, but I needed it in a .NET Standard 2.0 class library, so I was out of luck. My implementation is simple, not different from others I found online, and should also work fine with old ....

Fattura Elettronica for .NET v3.4.10 was released on NuGet today. The Fattura Elettronica project allows for the validation and de/serialization of electronic invoices following the Italian Revenue Agency standards. This release adds a missing validation point. See the changelog for details (Italian).

I’ve just received news that I’ve been awarded the Microsoft Most Valuable Professional (MVP) Award in the Software Development category. It is an honor and a pleasure to be renewed for the eighth time. Being a Microsoft MVP means a lot to me; I remember how intimidated I felt when I met MVPs at various events and how totally out of reach the title seemed for someone like me. Besides my everyday work, I kept doing the things I loved:...

Another day another Homebrew incompatibility emerges, this time with docfx, the technical documentation building tool of reference in .NET space. I’ve been using docfx for years to build the FatturaElettronica.NET website, and it’s always been working without a glitch. Lately, however, my builds have been failing with strange errors I was too lazy to diagnose until today when I decided to grasp the nettle and sort the whole thing out....