python

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. ...

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....

Today I released Eve 0.6.2. It includes many fixes and improvements over the previous releases. Areas addressed are CORS management, soft deletes, token authentication, oplog, data validation, and others. Please see the changelog for details. Work on v0.7 is also ongoing. It will include new features such as support for the MongoDB Aggregation Framework (docs) and a few breaking changes, so you might want to check it out in advance....

A new version of Eve, the REST API framework for Humans, has been released today. Following the 0.6 milestone released one month ago, v0.6.1 introduces some fixes and few new important features. Upgrade is strongly encouraged. As always, a changelog with full list of updates is available.

The slides of my talk at Percona Live 2015 (Amsterdam) are online. It was titled “MongoDB and REST APIs a Match Made in Heaven” and it was meant as an introduction to Mongo, REST principles and the Eve python framework. Overall it has been a pleasant experience, although I found that splitting 300 attendees through seven concurrent tracks ultimately led to too much fragmentation. People often found themselves with 2-3 interesting talks all happening simultaneously, and just had to pick one....

On Stack Overflow and the Eve mailing list, but also in my mailbox and even on Twitter, I get a lot of enquiries on how to build custom endpoints within a Eve-powered RESTful application. Now, since within Eve all endpoints are fully customizable, what they really mean is: How do I setup endpoints without any binding to a data entity, just connected to a custom method? They would like to call something like /mycustomendpoint and get the response from a method they have defined somewhere in the Python sources....

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:...

I was lucky enough be the first guest for the shiny new Talk Python To Me Podcast hosted by Michael Kennedy. In this episode we talk about Eve an my other open source releases, which gives us an excuse to touch on a variety of topics such as Polyglot Programming, New Microsoft and the .NET evolution, MongoDB and the Open Source eco-system as seen from the point of view of an old fart who has been spending most of his career in closed systems....

Yesterday Cerberus 0.8.1 was released with a few little fixes, one of them being more a new feature than a fix really: sub-document fields can now be set as field dependencies by using a ‘dotted’ notation. So, suppose we set the following validation schema: schema = { 'test_field': { 'dependencies': [ 'a_dict.foo', 'a_dict.bar' ] }, 'a_dict': { 'type': 'dict', 'schema': { 'foo': {'type': 'string'}, 'bar': {'type': 'string'} } } } Then, we can validate a document like this:...

Eve 0.5.2 has just been released with a bunch of interesting fixes and documentation updates. See the changelog for details.