Re: [xri] ED07 Issue #1: Encoding of + in query parameters

[Victor Grey <victor@idcommons.org>]

> So the only thing we have to do to make the whole thing just work,  
> is forbid spaces in QXRI query params -- whether they are escaped  
> or not.

On reflection, I thought I should clarify this a bit:

Since the "+" symbol is a legacy encoding of the space character in  
URL query params, all of (at least) the LAMP languages unescape "+"  
to a space.

Since we -need- the "+" character in QXRI query params for mime- 
types, we deal with this in our php and ruby implementations by  
simply converting spaces in the query params back to "+"s.

This means that any actual space in a query param is going to get un- 
unescaped to a "+", whether it was originally percent encoded or not.

There are two ways to deal with this:
1. Require the "+" character in QXRI query params to be percent encoded.
2. State that QXRI query params SHOULD NOT contain spaces, escaped or  
otherwise, as they may be misinterpreted by applications as a "+"  
character.

I prefer 2.

I've never actually seen a literal space used in a query param, I  
think it would be quite rare. Further uglifying QXRI query params by  
requiring the "+" to be percent encoded to cover this rare corner  
case doesn't seem worth it to me.

=vg