1

I am puzzling over the following:

https://nominatim.openstreetmap.org/lookup?osm_ids=N1271595261 produces no results while
https://www.openstreetmap.org/node/1271595261 gives results - why would this be ? I need to do this programmatically and thus the nominatim is necessary, I believe.

2

Maybe because this node does not carry any tags? Try it with this one for example:

https://www.openstreetmap.org/node/4360749904
https://nominatim.openstreetmap.org/lookup?osm_ids=N4360749904

3

yes I suppose that would explain it, thank you

4

whoops , not so fast :confused:

https://nominatim.openstreetmap.org/lookup?osm_ids=N32870515

and

https://www.openstreetmap.org/node/32870515

belie this otherwise-alluring explanation

5

The node is certainly known to Nominatim: https://nominatim.openstreetmap.org/details.php?place_id=194799

I wonder if it has to do with the one node being part of a relation and the other not? Just guessing.

But I seriously wonder how a city can simultaneously be a water tower. https://www.openstreetmap.org/node/32870515

6

I don’t believe lookup by place id is recommended practice since the placeid can change per installation , iiuc. I am looking for how to get this data doing a node_id lookup - if there is no way to do it then I guess I will give up and use the placeid - anyone know what’s going on ? :frowning:

7

can someone with the requisite knowledge weigh in here? I seem to be forced to lookup by place id, is this standard practice?

8

I don’t understand why you ask nominatim when you already know the node id.

9

What is it you are actually trying to do? If people can understand that they might be able to help.

10

I am trying to get extra details about certain nodes from nominatim . For instance for cities in south america , I would like details such as containing district, country, altnames, etc.
To get a list of nodes e.g. representing s. america cities I can use osmfilter on the relevant .osm file.
With this list of nodes I can programmatically query nominatim to get the info I am after , to end up with a list of cities and containing districts.

However nominatim (https://nominatim.openstreetmap.org) will in many cases return nothing for a node, while the openstreetmap site (https://www.openstreetmap.org/node/) will at least recognize the node and further show some of the details that I am interested in.

I would like to get the node and extra information usually available from nominatim but am not clear why no results are forthcoming from a simple lookup for many nodes (eg
https://nominatim.openstreetmap.org/lookup?osm_ids=N32870515&addressdetails=1&extratags=1 returns nothing , and
https://nominatim.openstreetmap.org/reverse?osm_type=N&osm_id=32870515&format=json returns ‘unable to geocode’,
while the osm lookup
https://www.openstreetmap.org/node/32870515 returns the node details plus extra information such as is_in info ).

In other cases nominatim does fine, eg.
https://nominatim.openstreetmap.org/lookup?osm_ids=N107775&addressdetails=1&extratags=1

11

I am looking for the data about the node that nominatim sometimes provides and osm usually provides, for instance within which city/state/country the node resides, alt names, etc.

12

Risking to state the obvious: The is_in information is not computed, it is a tag of the node added by a mapper.

13

Yes, the is_in is in the node tags (and is not always provided) ; in this case I misspoke and am looking for the extra computed info ; containing county/district/country etc. (computed information in the style of the is_in tags, namely what objects contain the node) .
There is a fundamental question here , namely why nominatim returns ‘cannot geocode’ for many nodes when using the api node lookup functions (lookup and reverse) . I wonder what is going on behind the scenes at the openstreetmap.org lookup , if it is augmenting nominatim somehow?

14

I guess that nominatim doesn’t store the information for all nodes in the OSM db, only for those which have a place_id.

15

It seems to be true.

Node 54 for instance representing the major city Novosibirsk has no place id and thus the nominatim node id search returns nothing. :confused:
I suppose what I need to do for such cases is search by name and area and hope to find other entities (ways/relations) that do have place ids; this is somewhat annoying since then I have to disambiguate the potential multiple results; the nice thing about a node lookup is the node serves as uid.

It seems somewhat more involved than necessary; is there some reason not every node tagged ‘city’ gets the honor of a place id (or alternately why nominatim will not return anything but items with place id?)

Now that i think of it I suppose in my original osmfilter run I should find not only nodes but also ways and relations tagged as city , and perhaps of those at least one will have a place id and thus be found in nominatim.

In any case thanks for your help, this has been useful.

16

Just in case it might help: In the mkgmap project (1) we compute a file bounds.zip which contains the admin boundaries in a way that allows
to retrieve the wanted information for any position. In mkgmap it is used to fill search indexes.
You can use this functionality to produce a file that contains the osm id and the enclosing boundaries.

Edit: I described this here: https://forum.openstreetmap.org/viewtopic.php?pid=692800#p692800

(1) http://www.mkgmap.org.uk/