is there any easy way, like an online renderer or a function in JOSM (which I use for editing), to search for objects that lack certain attributes? I have no experience with command line tools or the like, so an easy to use solution would be great and help me much with my mapping projects:
e.g.: I want to improve the availability or precision of the “surface” description in a certain area. Therefore I want to find all streets in that area that still miss the “surface” attribute or all streets that have only the general “paved”-attribute as an attribute without detailed specification; so I can visit those streets and amend the proper attributes.
You can also do this with two step searches if you find the detailed search syntax confusing:
Find all your objects e.g., highway
Remove from your current set of selected objects all objects with surface
Remove and Search within allow reasonably complicated processes which sometimes need a fair bit of fiddling with to get right with the text search syntax
I normally then use the ToDo plugin to step through each object found in the search & edit it appropriately, although this might not be needed if you are sure all ways have asphalt surfaces (almost guaranteed to be an exception though).
Before downloading an entire area or its objects, you can also query on Overpass Turbo online before exporting the objects or area you want to edit to JOSM. This can make work more focused.