Car Profile: Handling of highway=primary/secondary/… + construction!=yes

[Nakaner]

While testing the osrm-components and comparing the output of different profiles, I found a routing error which is strange to my understanding as an experienced mapper.

This issue is related to #4230.

The primary road B 47 eastwards between the two roundabouts is flagged as border. It took some time to discover why it was flagged: The western roundabout is tagged highway=primary + construction=primary. This is a left-over of the time when it was build (according to note=* tags in that area in May 2014).

While Daniel's pull request improved the handling of highway=primary/secondary/… + construction=yes, it broke the handling of these partially broken tagging like this roundabout in Amorbach.

The number of highway=primary/secondary/… + construction=yes will decline in the next months because Geofabrik will add two additional layers to the OpenStreetMap Inspector which highlight misleading tagging (highway/railway/shop/amenity=<under operation> + construction=yes) in a few days. As a side effect, they will also mark construction!=no with highway!=construction.

Used OSRM version: 5.9.2, OSM data less than 3 days old

[emiltin]

I think what you're describing is a mapping error, or do you propose any change to the code?

[Nakaner]

It is a mapping error but construction=yes + highway=primary is also a mapping error but supported by the car profile (it treats it as construction). I propose either a change to the code or a "won't fix" statement.

[daniel-j-h]

We discard construction ways (except: no, widening, minor) in the default profile on purpose to incentivize proper tagging. Feel free to disable the construction tag handling in your own profile modifications.

Note: the same applies to the proposed tag.

[maraf24]

We discard construction ways (except: no, widening, minor) in the default profile on purpose to incentivize proper tagging.

This doesn't really work. There are thousand of roads with construction= leftovers in osm data and OSRM doesn't route through them today.
Fixing this is non-ending work, as people are generally unaware of the problem and the most popular editor, iD, is main culprit here.

[danpat]

You can toggle this off in the car profile here:

https://github.com/Project-OSRM/osrm-backend/blob/master/profiles/car.lua#L136

comment out that line, and construction=yes will get ignored. It's probably worth making that the default....

[maraf24]

This will also allow routing via highway=construction, if I correctly understand code in way_handlers.lua.

[danpat]

Yes, it will - but similar to construction=yes, I've found that the majority of those are stale too.