open source

I just released a long overdue update to Eve.NET. This release marks a significant improvement over the previous one, which was more a prototype than a real package. New features are as follows: PostAsync() supports bulk inserts DeleteAsync() supports bulk deletes GetAsync() has a softDelete option to include soft-deleted documents with query results GetAsync() has a rawQuery option to pass raw Eve queries to the server BearerAuthenticator class adds support for Bearer Token authentication Several fixes made it into this release and, most importantly, I switched to portable Profile259 which offers support for the following platforms: Xamarin. »

SimpleObjectCache is a very simple permanent, cross-platform, asynchronous key-value object cache for .NET. It comes with built-in SQLite 3 support. Alternative backends can be added by implementing the IObjectCache or IBulkObjectCache interfaces. How it works First, you need to set the ApplicatioName. This is also going to be the folder where your cache will reside. Depending on the host OS the location of this folder might be different. On Windows it would be something like C:\ProgramData\<ApplicationName>\SimpleObjectCache. »

Released by the nice folks at Drud, EveGenie is a tool for making Eve schema generation easier. Eve’s schema definitions are full of features, but can take a good amount of time to create when dealing with lots of complex resources. From our experience, it’s often helpful to describe an endpoint in JSON before creating it as an Eve schema. This allows you to make quick decisions about the structure of your entities without spending time moving schema code around. »

Quick note to let you all know that Eve v0.6.4 is out with a few significant updates. Thanks to James Stewart for contributing to this release. Work on v0.7, which will include MongoDB Aggregation Framework support (docs) and many other new features, continues steadily. »

Cerberus is a lightweight and extensible data validation library for Python. Beta has been around since 2012. During this time Cerberus has been serving as the validation system for Eve core. It has been also adopted by a quite a lot open source projects, averaging around 18K downloads per month on PyPI and collecting some remarkable endorsements.

All things considered, I would dare to claim that Cerberus is battle tested to death. This is, in fact, one reason why I believe that the time for a canonical and stable release has come. Another reason is that next release is a major one. It brings a ton of important new features along with very significant code refactoring and a redesigned, powerful API. Third, next release breaks backward compatibility, and we want to signal that in the version number.

So next Cerberus release will be 1.0. If you have been following the development this will come as no surprise, as a Release Candidate has been out for a while. As a Cerberus user you will want to take the plunge and upgrade to 1.0 because well, it is just too cool to be true. If new to Cerberus you will also want to adopt 1.0 right away, for the same reason. If you are new however, make sure you get the basics covered before reading further. By the way, at latest PyCon Italy I gave a talk on Cerberus which also included a preview of several 1.0 features. You can check the slides to get a general idea of the tool, its usage, and upcoming features.

Let’s now look at some of the relevant features and changes introduced with Cerberus 1.0. For a (mostly) accurate list of changes and new features, have a look at the changelog.

Ho appena pubblicato su NuGet l’ultimo aggiornamento di FatturaElettronicaPA, il package .NET per la compilazione e convalida delle fatture elettroniche per la Pubblica Amministrazione. Si tratta della versione 0.2.1 che fa proprie le novità annunciate il 9 Maggio scorso: A partire dal 9 maggio 2016 sono introdotti nuovi controlli sui file trasmessi al Sistema di Interscambio. Per consentire il necessario adeguamento al nuovo regime di verifiche, fino al 31 luglio 2016 il mancato superamento di uno o più di questi nuovi controlli non comporterà lo scarto del file ma solo una segnalazione che verrà riportata all’interno della Ricevuta di consegna o della Notifica di mancata consegna. »

April was definitely my crazy Speaking Month. After an almost one year long self-imposed conference hiatus, I was challenged to deliver four different talks, attend two discussion panels, give one live demo and release one interview. All in a three weeks period span. First I went to PyCon Sette in Florence. A few days later a plane took me to St. Petersburg, Russia, for PiterPy. Finally, the next weekend I was in Rome for the Western Europe Microsoft MVP Community Day. »

FatturaElettronicaPA has just been updated to v0.1.4. With this release invoice bodies (FatturaElettronicaBody items) are also validated. As always, you can install the package directly from NuGet. See the original post for more info. Also don’t forget to check the related projects. Update: v0.1.6 has also been released. »

A few days ago Cerberus 0.9 was released. It includes a bunch of new cool features, let’s browse through some of them. Collection rules First up is the new set of anyof, allof, noneof and oneof validation rules. anyof allows you to list multiple sets of rules to validate against. The field will be considered valid if it validates against one set in the list. For example, to verify that a property is a number between 0 and 10 or 100 and 110, you could do the following: »

this post is about an all-Italian open source release, so it’s going to be in Italian Il progetto Fattura Elettronica Open Source si è arricchito di un nuovo strumento: Web Services. Il namespace FatturaElettronicaPA.WebServices raccoglie una serie di client C# che consentono di consultare i Web Service per la Fattura Elettronica messi a disposizione dalla Pubblica Amministrazione. Sono disegnati in maniera da esporre tutti la stessa interfaccia ed essere al tempo stesso semplici e leggeri. »

Fattura Elettronica Open Source has been updated to v0.1.3 a few days ago and is available on NuGet. Sources are on GitHub. It fixes a deserialization issue with the ReadXML method. »

I have a guest post up at the official Italian MSDN Team Blog. It’s about the new Microsoft I met last Wednesday at the Azure Open Day in Milan. »

this post is about an all-italian open source release, so it’s going to be in italian

FatturaElettronicaPA è un nuovo progetto open source che ho rilasciato qualche giorno fa assieme alla mia azienda. Si tratta di una libreria C# che permette di leggere, scrivere e convalidare le Fatture Elettroniche aderenti alle specifiche del sistema di interscambio della Pubblica Amministrazione.

Tom Christie has some very good things to say on how to successfully maintain an open source project without losing sanity. Truth one: There are, and will always be, a non-finite number of possible valid issues to address. Your code can always be better polished, your APIs better defined, and your project more fully featured. Your documentation can always be better. The ecosystem within which your project lives is constantly evolving. »

Like all those involved with the .NET ecosystem I’ve been slowly digesting the recent news on the whole thing going open source and cross platform. I’ve been jogging down a few notes in light of a future blog post, but then Jeremy Miller came out with his own Some Thoughts on the New .NET which is almost exactly the post I wanted to write. So when he writes: I’ve started to associate . »

Eve.NET is a simple HTTP and REST client for Web Services powered by the Eve Framework. It leverages both System.Net.HttpClient and Json.NET to provide the best possible Eve experience on the .NET platform.

Written and maintained by the same author of the Eve Framework itself, Eve.NET is delivered as a portable library (PCL) and runs seamlessly on .NET4, Mono, Xamarin.iOS, Xamarin.Android, Windows Phone 8 and Windows 8. We use Eve.NET internally to power our iOS, Web and Windows applications.

Last week I was speaking at an Open Source panel at Better Software 2014, and one of the topics that we touched was code responsibility. This is an important topic for anyone who is maintaining an open source project, especially when it comes to the process of reviewing and accepting code contributions.

At some point during the debate, I argued that when a maintainer merges a pull request, he (or she) implicitly agrees on being responsible for that code. That seemed to strike some surprise into most attendees.

Yes, in theory any contributor is just a ping away so in case trouble arises one can always reach him, or her. Unfortunately this is not always the case. While some contributors will fully embrace your project and keep helping after their initial contribution, truth is that a good number of them will just move on, never to be seen again.

There’s nothing wrong with that. Not everyone has spare time to devote to your project, which is perfectly fine. It is natural for most people to contribute what they need to a project and then go on their way. Actually, one could argue that most projects grow and prosper precisely thanks to this kind of contributions.

However this attitude can become an incumbent when big chunks of code get merged, usually as new (big) features. Good practices advice against merging huge pull requests. In fact they are rare and when they do come, it is a good idea to ask for them to be split into smaller ones. But no matter the format, a huge contribution is likely to hit a project one day or another. It might even come from more than one person: a disconnected and distributed team of contributors who have been patiently tinkering on a side branch or a fork for example. When this happens, and provided that the contribution is worth merging, the maintainer should then ask him/herself the obvious question: am I willing to deal with the consequences of this merge?

Most significant features are probably the native support for MongoDB write concern settings, new event hooks allowing for transformation of documents before they are sent to clients, increased handling of both pagination and CORS, and the native validation of float data types. Get it on PyPI, go straight to the source code or more likely, visit the project homepage. »

Gli eventi sono molto usati nelle GUI e nelle implementazioni del modello MVC (Model, View, Controller). Un’altra applicazione tipica è nei protocolli di comunicazione, laddove layer di basso livello devono informare quelli più alti quando ci sono dati in ingresso o in uscita.

Il linguaggio C# dispone da sempre di una soluzione elegante al problema della gestione degli eventi: il delegato EventHandler. Events è una mia implementazione Python del EventHandler C#. In pratica si tratta di una classe molto leggera che incapsula il cuore del meccanismo di sottoscrizione e gestione degli eventi, e tenta di farlo in maniera “naturale”, sembrando parte integrante del linguaggio Python.

Da qualche giorno ho rilasciato Cerberus, uno strumento per la convalida dei dizionari Python. Gli passate un dizionario, lui lo confronta con uno schema di convalida e, se c’è qualcosa che non va (per esempio una chiave sconosciuta, oppure un valore di tipo sbagliato), ve lo segnala. >>> v = Validator({'name': {'type': 'string'}}) >>> v.validate({'name': 'john doe'}) True Sono due le caratteristiche che rendono Cerberus interessante: è facilmente estensibile (la documentazione include un esempio di estensione del sistema di convalida), e non si blocca sollevando un’eccezione al primo problema riscontrato: gli errori, quando presenti, sono tutti riportati in una lista a fine convalida. »