URL query string convention for multiple sort

Question

I have a RESTful web application that supports multiple sort fields on a collection of items. Is there a common convention for encoding these sort fields into the query string of a URL? I'm considering a pattern like the following:

http://myapp.com/books?sort=author:asc,datepublished:desc&count=12 

This would sort the collection of books by author and then by date published.

Basically, I need a convenient way for the name-value pairs in my query string to have name-value pairs of their own. I'll need to do something similar to the above example for filter parameters, too.

Does Rails or ASP.NET MVC have a pattern for this? Are there other frameworks that have established ways for dealing with this issue? I'd rather use a familiar format than roll my own.

I'd also prefer a format that uses as little URL percent-encoding as possible.

Answer 1

I've done this before using the standard SQL sorting syntax. There are numerous parsing functions and techniques out there.

http://myapp.com/books?sort=author asc,datepublished desc&count=12

which would be encoded to

http://myapp.com/books?sort=author+asc,datepublished+desc&count=12

Answer 2

For REST, I prefer a more intuitive syntax:

http://myapp.com/books?sort=+author,-datepublished&count=12

And more elaborated (without '+' sign):

http://myapp.com/books?sort=author,-datepublished&count=12

Easy to remember...