AmFast Released!

I released the alpha version of AmFast today. AmFast is an AMF3 encoder/decoder Python extension.

Some un-sophisticated testing shows that AmFast is around ~18x quicker than PyAmf. 10,000 runs through the test_complex_encode_decode_dict() unit test takes ~105 seconds on my machine using PyAmf, and ~5.8 seconds using AmFast.

If you want to try it out, you can download the package from PyPi, and take a look at the meager documentation.

AmFast supports all of the data types that PyAmf does, but there is not yet any functionality for implementing remoting, or working with AMF0. I'm hoping that AmFast will be able to integrate into PyAmf, so that you can optionally use either the existing pure Python AMF3 encoder/decoder, or AmFast within the PyAmf framework.

This was my first time working with the Python C API, and I think it's pretty cool. Besides having to remember to increment and decrement Python object reference counts in the right spots, it was pretty easy to learn. I'm not anywhere near a C expert, and I wrote this extension in my spare time over the course of a couple of weeks.

PyAMF SQLAlchemy Adapter

PyAMF 0.4 was recently released, and the new code contains SQLAlchemy support by default, plus a bunch of other cool new features and bug fixes.

Check out my example Flex/PyAMF/SQLAlchemy project for ideas of how to get started with PyAMF and SQLAlchemy.

Using PyAMF and SQLAlchemy together

This past week I recieved the go-ahead to re-code the backend of our LIMS application with Python (it's currently PHP). It's not a minute too late, as I don't think I can stand typing another '->' or '$' without throwing something at the wall. I could go on about why I'm really sick of PHP and why Python rocks, but I'm sure you can read all about that elsewhere.

We'll be using Python's SQLAlchemy ORM, which kicks some serious ass. SQLAlchemy makes it amazingly simple to model complex relationships like inheritance hierarchies and many-to-many relationships that I could only implement with gobs of gnarly custom code in PHP.

Since we're already re-writing the backend we decided that we may as well tweak the Flex client at the same time. We are going to be making the switch from JSON to AMF for server-client communication, which will be more performant and allow us to transfer richer objects back and forth.

Python is pretty awesome for web-development, but the project that aims to support AMF (PyAmf) is still new and immature (but it does encode and decode as advertised and is under active development). In fact, the current stable release of PyAmf will not properly encode objects that are being managed by SQLAlchemy. There is a SQLAlchemy 'adapter' in the development branch of the PyAmf project that can be used, but I found the code to be lacking.

I decided to take matters into my own hands, and I am currently working on my own SQLAlchemy adapter that will hopefully work a little better. The code for my SQLAlchemy adapter can be found on Google code. It is not production ready, but if you want to experiment with it (tested only with SA 0.5), you should be able to drop it in the 'adapters' directory of the PyAmf 4.* branch to use it.

The adapter has 2 main features. It overrides the pyamf.util.get_attrs function so that the pyamf encoder skips any attributes of an object that are used by SQLAlchemy (_sa_instance_state, _sa_manager, etc), and it also identifies and translates SQLAlchemy collection objects, such as InstrumentedList objects.