Validator warning for syntactically invalid keys

[1ec5]

If the user manually adds a key that’s obviously inconsistent with conventional key syntax, iD should issue a validator warning in the upload panel. For example, a key that contains an uppercase letter (other than FIXME), a space, an accented character, or :: is likely to be either a typo or an opportunity to suggest a more appropriate tag to an inexperienced mapper. Such issues may be caught by QA tools, but the upload panel is an opportunity to clarify the mapper’s intent so that other mappers don’t have to guess.

On that note, a simple validator warning message like “Invalid key” may not adequately explain the problem to the mapper. Perhaps an ℹ️ button could open this set of guidelines or a fuller message with tips on finding the appropriate tag to use.

There are some additional ideas around validating punctuation in osmlab/osmlint#234. There, the focus was on name tags, but for keys we can be much more strict without worrying about false positives.

[bhousel]

This sounds a lot like #4579 which you opened a while ago.

[1ec5]

It does serve a similar purpose. This suggestion is purely about syntax, whereas #4579 would require hitting the taginfo or Wikibase API.

[quincylvania]

I'm all for this. It'd go great with #5830 since users would see the warning as soon as they enter the key.

[matkoniecz]

Note that tags may also contain (due to copy pasting) an invisible and unprintable characters - for example unicode bidi control ( see case for widespread bidi control character in https://josm.openstreetmap.de/ticket/17521 that caused https://github.com/openstreetmap/iD/issues/5895 ).

[bhousel]

Note that tags may also contain (due to copy pasting) an invisible and unprintable characters - for example unicode bidi control ( see case for widespread bidi control character in https://josm.openstreetmap.de/ticket/17521 that caused #5895 ).

I think iD already strips these out for things that look like URLs, however we wouldn't really know which out of all the millions of tags in OSM are allowed to contain these characters.

https://github.com/openstreetmap/iD/blob/d76baa9b8365f656c0996313fe13149d2fce2077/modules/util/clean_tags.js#L30-L39

[pnorman]

Checking tags would be fraught with problems, but keys should be safe.

[quincylvania]

I think we should do this under the "Invalid Formatting" validation rule added in #6494. We also have ℹ️ issue reference buttons now to explain specific syntax violations.