Get BFS-Nr from Coordinate - API swissboundaries3d-gemeinde-flaeche-fill

[mic...@gmail.com]

I used to be able to use the following call to the geo admin API using ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill  to get the actual corresponding BFS-Nr of a coordinate using this call with an example point in Zurich Oerlikon.

https://api3.geo.admin.ch/rest/services/all/MapServer/identify?geometry=683344,251660&geometryFormat=geojson&geometryType=esriGeometryPoint&imageDisplay=1000,1000,96&lang=en&layers=all:ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill&limit=1&returnGeometry=false&sr=21781&tolerance=0

Result in April 2024, BFS-Nr is bold:
{"results": [{"layerBodId": "ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill", "layerName": "Municipal boundaries", "featureId": 261, "id": 261, "properties": {"gemname": "Z\u00fcrich", "gemflaeche": 9188.0, "perimeter": 58636.99647325312, "kanton": "ZH", "objektart": 0, "label": "Z\u00fcrich"}}]}

The current response of the same query gives a lot of history on this specific point and links where I could figure out the current BFS by digesting all changes, but it does not return the current BFS-Id. 

Query Result as of March 2025:
{"results": [{"layerBodId": "ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill", "layerName": "Municipal boundaries", "featureId": "16458-1875", "id": "16458-1875", "properties": {"gemname": "Oerlikon", "gemflaeche": 265.0331599743301, "gde_hist_id": 16458, "gde_nr": 7700, "jahr": 1875, "perimeter": 7888.425209554802, "kanton": "ZH", "objektart": 11, "is_current_jahr": false, "objektart_lookup": "politische_gemeinde", "link_de": "https://www.agvchapp.bfs.admin.ch/de/communes/results?BfsNr=7700&EntriesFrom=01.01.1872&EntriesTo=31.12.1933&IncludeUnassignedEntities=True", "link_fr": "https://www.agvchapp.bfs.admin.ch/fr/communes/results?BfsNr=7700&EntriesFrom=01.01.1872&EntriesTo=31.12.1933&IncludeUnassignedEntities=True", "link_it": "https://www.agvchapp.bfs.admin.ch/it/communes/results?BfsNr=7700&EntriesFrom=01.01.1872&EntriesTo=31.12.1933&IncludeUnassignedEntities=True", "label": "Oerlikon"}}]}

Questions:

- How to build a new query that give me back the functionality I need?

- What expectations on stability in the response can I have on any queries I am running against an established dataset? Am I wrong to assume that responses to queries of established datasets should not start to exclude previous content? 

- How do I manage to keep track of changes so production is not affected due to upstream changes?

Thanks, Michael

[tr.tobi...@gmail.com]

Hej

Meanwhile this layer has a timeseries from 1850 onward. The id is just an id. But yes, to keep uniqueness it is now a combination of bfs number and year for former gemeinden. Fx. 261-2024 (bfs number - year):

https://api3.geo.admin.ch/rest/services/all/MapServer/identify?geometry=683344,251660&geometryFormat=geojson&geometryType=esriGeometryPoint&imageDisplay=1000,1000,96&lang=en&layers=all:ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill&limit=10&returnGeometry=false&sr=21781&tolerance=0&timeInstant=2024

The recent gemeinden (currenlty 2025) are only composed of the bfs number: https://api3.geo.admin.ch/rest/services/all/MapServer/identify?geometry=683344,251660&geometryFormat=geojson&geometryType=esriGeometryPoint&imageDisplay=1000,1000,96&lang=en&layers=all:ch.swisstopo.swissboundaries3d-gemeinde-flaeche.fill&limit=10&returnGeometry=false&sr=21781&tolerance=0&timeInstant=2025

The GET-key timeInstant is important here.

To keep track, you can keep an eye on the release notes: https://api3.geo.admin.ch/releasenotes/index.html#release-20231220-wednesday-december-20th-2023

I hope this answers help you.

BR, Tobias