How to mitigate Rest resource that keeps changing its path

[Mariusthvdb (Marius)]

using resource https://data.buienradar.nl/2.0/feed/json, I am looking for the station Woensdrecht, and find it at 49:

rest:

  - resource: https://data.buienradar.nl/2.0/feed/json
    scan_interval: 86400
    sensor:
      - unique_id: rest_sensor_buienradar_woensdrecht
        name: Buienradar Woensdrecht
        value_template: >
          {{value_json.actual.stationmeasurements.49.regio}}
        json_attributes_path: '$.actual.stationmeasurements.49'
        json_attributes:
          - timestamp
          - weatherdescription
          - etc

however, the station number changes almost daily, so my sensors go un available, or show data for another station altogether…
fwiw, this is the full json for the station:

{"$id":"53","stationid":6340,
 "stationname":"Meetstation Woensdrecht",
 "lat":51.45,"lon":4.33,
 "regio":"Woensdrecht","timestamp":"2025-02-18T07:30:00",
 "weatherdescription":"Zwaar bewolkt",
 "iconurl":"https://www.buienradar.nl/resources/images/icons/weather/30x30/cc.png",
 "fullIconUrl":"https://www.buienradar.nl/resources/images/icons/weather/96x96/CC.png",
 "graphUrl":"https://www.buienradar.nl/nederland/weerbericht/weergrafieken/cc",
 "winddirection":"O","airpressure":1024.7,"temperature":-5.0,
 "groundtemperature":-6.7,"feeltemperature":-9.5,
 "visibility":12300.0,"windgusts":3.8,
 "windspeed":3.0,"windspeedBft":2,
 "humidity":86.0,"precipitation":0.0,
 "rainFallLast24Hour":0.0,"rainFallLastHour":0.0,
 "winddirectiondegrees":80}

that was yesterday, check today, it’s back to 38 …

Cant I somehow search for the correct stationid/stationname in that json attributes path and be immune to that frequent change, and find the correct endpoint automatically?

[Mayhem_SWE (Magnus)]

Have you at all looked at the documentation RESTful Sensor documentation? It links to an explanation of how to write a JSONPath, though I have used neither before it can’t have taken me more than two minutes to figure out that the json_attributes_path probably should be something like this:

$.actual.stationmeasurements[?(@.stationid == 6340)]

Edited to remove trailing [0] which somehow wasn’t correct.

[Mariusthvdb (Marius)]

@Mayhem_SWE

$.actual.stationmeasurements[?(@.stationid == 6340)][0]

Tbh, I didnt see that no. thanks for the pointer.

However, it does not yet work as hoped for (I’ve moved the value_template for the time being to now(), as that requires even more syntax checking)

      - unique_id: rest_sensor_buienradar_woensdrecht
        name: Buienradar Woensdrecht
        value_template: >
          {{now()}}
#           {{value_json.actual.stationmeasurements[?(@.stationid == 6340)].regio}}
        json_attributes_path: '$.actual.stationmeasurements[?(@.stationid == 6340)][0]'
        json_attributes:
          - timestamp
          - weatherdescription
          - winddirection
          - $id
          - stationid
          - stationname
          - winddirection

results in the following:

so the path is not set correctly, and none of the attributes is listed because of that.
nothing in the logs.

edit
this works though:

        json_attributes_path: '$.actual.stationmeasurements[?(@.stationid == 6340)]'
        json_attributes:
          - timestamp
          - weatherdescription
          - winddirection

sweet!
now get that station name back in the value_template, because this is returned:

Invalid config for 'rest' at packages/package_weer.yaml, line 993: invalid template (TemplateSyntaxError: unexpected char '?' at 40) for dictionary value 'rest->8->sensor->8->value_template', got '{{value_json.actual.stationmeasurements[?(@.stationid == 6340)].regio}}\n', please check the docs at https://www.home-assistant.io/integrations/rest

using the same string

        value_template: >
          {{value_json.actual.stationmeasurements[?(@.stationid == 6340)].regio}}

[Mayhem_SWE (Magnus)]

Well as I said I’ve never used JSONPath before. Using an online evaluator just now I came to the same conclusion, but I really don’t understand why. As I expected from the documentation, the result is displayed as a list, so it makes no sense why one wouldn’t also need to actually get the first item of this list with a [0] or .0 at the end… Ohh well, at least it works!

[Mariusthvdb (Marius)]

@Mayhem_SWE

Ohh well, at least it works!

yes, at least for the most part of it.

I cant seem to find the correct syntax using that same path in the value_template however.
Somehow it doesnt like the ? but I can not escape it correctly

[Mayhem_SWE (Magnus)]

The value_template is not a JSONPath, it is a Jinja template. Entirely different language/syntax. Should be something like this:

(value_json.actual.stationmeasurements | selectattr('stationid', '==', 6340) | first)['regio']

[Mariusthvdb (Marius)]

of course… I kept thinking the wrong way…

result is great now:
thank you so much