Python Posts

I've just released version 2.0.3 of PyFilesystem.

PyFilesystem is an abstraction layer for filesystems (or anything that resembles a filesystem). See this post for more details.

New in this version is a TarFS filesystem contributed by Martin Larralde, which compliments ZipFS nicely.

Contributed by gpcimino, the copy module was extended new functionality to selectively copy only new files from one filesystem to another. Very useful for backups.

This is in addition to bugfixes, and improved documentation.

It's not often I come across something in Python that surprises me. Especially in something as mundane as string operations, but I guess Python still has a trick or two up its sleeve.

Have a look at this string:

How many possible sub-strings are in s? To put it another away, how many values of x are there where the expression x in s is true?

Turns out it is 2.

2?

Yes, 2.

The empty string is in the string "A". In fact, it's in all the strings.

Turns out the empty string has been hiding every where in my code.

Not a complaint, I'm sure the rationale is completely sound. And it turned out to be quite useful. I had a couple of lines of code that looked something like this: continue reading…

This SO post prompted me to think about how you would go about customizing a entire Django site (not just an app). Particularly if it is a third party project, still in development.

Forking the site repository is a solution, but the more customizations you make, the more awkward it becomes to merge upstream fixes and features. The problem is compounded if you have multiple deploys, with custom templates, assets, and settings.

I wanted to do a quick write-up of how this would be done in Moya, where customization is more of a first-class concept.

I'll briefly go over how you would serve a Moya site with a custom template, without modifying any of the original files. The project I'll be customizing is Moya Techblog which power this blog. continue reading…

Just landed in inthing is a new and quite interesting feature.

Version 0.1.4 adds a capture method which will record all standard output, i.e. anything you print to the terminal. It works as a context manager. Here's an example:

Any print statement inside the with block will be captured and posted online with the block exits.

You can also do something similar from the command line, with the inthing capture subcommand, which posts anything you pipe in to it as an event.

lets say you wanted to post the version of all you installed Python packages online. You could do something like the following:

For more information see the Inthing docs.

Inthing is still technically in beta, but these features are quite solid. Please give them a try, and let me know how it goes!

The Django code in this post comes from the official Django tutorial.

I've tried not to be disingenuous with the comparison, and I'm only going to compare like with like, so I can show code from both frameworks and let you draw your own conclusions. I'll cover the areas where they differ in another post.

Both Moya and Django use models to map databases on to familiar data structures. In the case of Moya, the mapping is done with SQLAlchemy. Django uses its own ORM.

Here's the models.py from the Django tutorial and a Moya version: continue reading…

One of my goals for inthing.io was to make posting events realtime, in that events appear without a page refresh, and within a fraction of a second. And that largely seems to work.

Here's a quick screencast that shows it working:

I'll post about how it works in detail at some point, but the general gist is that there is a Tornado websocket server that inthing uses to broadcast information about updates. That server may be worth open-sourcing if there is enough interest. It could be useful for other projects, and its entirely independent.