validating a string when 'valid' in unknown

vtb

This is a language-neutral problem. Here's the story: I've written a substantial php/mysql application for use in my own workplace. It manages the scheduling of court interpreters for court proceedings.

I want to write a second version that avoids all the mistakes I made the first time around (insofar as possible :p), and I want to make it easy to pack up and ship off for installation elsewhere so others can use it too.

One of the tables has a column for the case docket number. Different courts have different formats for their docket numbers. Ours typically look like this: 02CR786 but others' aren't necessarily so. So the question is (sorry for the long intro): how do you approach the problem of validating a string when you don't know what format to validate against? I can imagine a setup/config routine where you ask the user to tell you, but YOW! that sounds complicated.

David Mintz
US District Court, SDNY
http://davidmintz.org/

jpmoriarty

yeah i think you've hit on the head one of the main problems with developing for delpoyment - when you start worrying about what people are going to be putting in, the problem just increases exponentially.

I dont think there's a way around it - which i guess is nature's way of trying to stop you making lots of money from your application 🙂

vtb

Make money? Moi? Actually I was planning to give it away. Well ok, maybe then hire myself out to them for support/consulting 🆒

One idea I had was conditional validation. Have a config file that has a variable containing either a regexp to use to validate against the string, or else null (or false or something like that). If there's a pattern in that variable, validate against it; otherwise let them input whatever they want (ouch). Then, in the documentation, say "dude, if you know what you're doing, hack this line in the config file." It is open source after all.

Sound reasonable?