I’m adding some information regarding the parking state in Frankfurt am Main in some areas. I have studied the wiki’s street parking page on the tagging rules and I’m trying to comply with all the tagging schemas explained there. However, I didn’t find any tags about the date of the source I’m using to derive the data, for example, the date I visited the street or the date that an image was captured and I’m using this tag for it:
Normally it is not necessary to specify the date on which a particular Tag of an element was checked. This information is already available when viewing the history of the object and ideally all relevant information is in the changeset itself (date, source, etc.).
If I collect data and fotos on a particular date and edit OSM data three days later I typically mention the date of collection in the changeset comment. This also helps me to find my foto when I look at the history of an object.
If it is a street (highway=*) with on-street parking spaces (parking:*), then I find a check_date misleading, as it does not indicate what exactly was checked. In the case of a street, this could affect all tags including maxspeed, surface, smoothness, sidewalk, cycleway, parking, name, highway, width, oneway and so much more.
As a data consumer, I would then ask myself: Was all this checked on that day?
StreetComplete uses check_date:parking=yyyy-mm-dd. (It only updates this date when the parking situation was changed and the tag is already set. Currently it does not add it on it’s own)
