[OSM-dev] Disallowing certain characters in tag keys

[Anthony]

On Sat, Oct 16, 2010 at 2:44 PM, Jochen Topf <jochen at remote.org> wrote:
> Technically this would mean changing the API to check
> for those characters, removing any that are already in the database (can be
> done with normal manual edits because there are so few cases) and adding checks
> to the editors so that they can give meaningful error messages.

To be clear, they'd still be in the database, in the history.

Which is one implementation problem, because it means putting checks
in more than one different place.  At the very least, the regular API,
and the Potlatch API, but there are probably multiple places within
the regular API where things would need to be checked.

And then any software which relies on these changes wouldn't work with
historical data.

It could be done, but to do all that work just to make it easier to
code Taginfo would be, in my opinion, a waste.  Especially when there
are plenty of simple solutions within taginfo.  If URL encoding is too
painful, use a modified base64 encoding of the unicode string (using
"-" and "_" instead of "+" and "/").

For cleaning up the keys, I'd want to strip down to as few characters
as possible.  There's no point supporting most unicode characters -
keys are supposed to be in English.