I wrapped up my C# 12 session at the ABP Dotnet Conference 2024, and I wanted to share the take-home points, at least about the most relevant features in this language version. Posting the slides made no sense as they were minimal; all the content was packed in the live demo. In a follow-up post, I plan to address Collection Expressions (done) and maybe “type any aliases”; this is about Primary Constructors. ...
I am thrilled to have the opportunity to present at an international conference once again. On May 9th, I will speak at the ABP Donet Conf'24. My session, titled C #12: What’s New and Interesting, is on a topic I’m passionate about. With the alignment of C# and Dotnet Core release cycles, the C# release cadence has increased (we’re on a yearly cycle now), while feature quantity has reduced for individual releases, which is good. The faster, smaller iterations allow for quicker course corrections, and introducing fewer new features makes it easier to embrace the changes. ...
I am speaking about OAuth2 and Open ID Connect with ASP.NET Core 8 at Rome .NET Conference 2024 on March 22 and then, less than a week later, at WebDay 2024 in Milan. I am always particularly excited when I can present the stuff I’m currently working on. Being forced to share as I learn encourages me to go deeper into the topic to reinforce my comprehension and better explain it to the audience—a win-win situation. ...
Today, I learned the hard way that the default port for ASP.NET Core 8 container images has been updated from port 80 to 8080, quite a remarkable breaking change. We upgraded our web application from .NET 7 and let the CI pipeline do its work. Finally, we checked the application in the browser to ensure everything was okay, but unfortunately, we got a 502 Bad Gateway error. The Nginx logs revealed that the app was rejecting connections, which was unexpected because we didn’t make any changes there. Further investigation showed that the web app listened on port 8080 while Nginx was reverse-proxied to 80. So that was the problem. But why did the port change? ...
The video and slides of my C# 12 session at .NET Conference Italia 2023 is finally available online. Unfortunately it’s just my voice and my laptop screen, and that’s too bad because the location was as cool as it can get, and the room was packed. It is in Italian1 and you need to login in order to see it (sorry, I don’t have control over it.) I also submitted to several international conferences; let’s see what happens. Since the COVID hiatus, I’ve had no luck with international events. ↩︎ ...
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. I searched online and found a two years-old ticket hinting at some problems between .NET 8 and older Docker versions. ...
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. Now that the final release is out, it will be interesting to return to the topic to consolidate my knowledge. I suspect that of the many reasons I challenge myself to speak publicly, enriching my knowledge is prevalent. As the adage goes, for learning a subject, nothing beats explaining it in front of a knowledgeable audience. ...
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. StringWriter exposes an Encoding property, but it is read-only for unknown reasons. One might think that given that the XmlWriter allows setting its own Encoding value, something like this would work: ...