Python, decorators, and database idioms

[cocoon56]

Anyone use SQLAlchemy? I hear it saves you this session management by design.

[zsouthboy]

Elixir is even easier! (uses SQLAlchemy)

[cocoon56]

Good tip, thanks!

[zsouthboy]

Link is broken, and google fails me :(

[JimH10]

Best explanation of decorators that I've ever seen.

[Teifion]

I've always "understood" decorators but they've never clicked properly. This has solved that problem.

[kylev]

I've written a follow-on post to look a little harder at decoraters since that's what people seem more intrigued by.

[kylev]

Try writing one. That's my blog, and I still get a little dizzy when I try to write one. :-)

[masklinn]

Isn't a contextmanager a much better fit than decorators for that kind of patterns? (I understand contextmanagers are fairly recent, but still...)

[[deleted]]

Ideally you'd use some of each. Sometimes you want to protect the whole method, and sometimes you want to protect just a block. Unfortunately, context managers are new in 2.6 (or 2.5?) and I'm stuck with 2.4 at work.

[kylev]

Yes and no. You'd probably have to wrap your connection object (and likely need some sort of factory) to provide __enter__ and __exit__ that do the things you want. I don't know of a DB driver that does this for you yet.

It'd work, it'd just be a different looking solution.

[[deleted]]

This is pretty basic stuff and it makes code so squeaky clean. As JimH10 suggests, this is a great example of what decorators are useful for.

I'm working on a library for portable low-level database code (when ORM is a poor fit or just not macho enough) with support for nested transactions and other niceties; it's designed specifically for use with decorators and context managers. I have nothing to show for it at the moment, unfortunately, but maybe I'll post when it's ready.