Extraction of feature type `verticalprofile` throws Timedelta error

[uandrae]

What happened?

With:

from polytope.api import Client

collection = "deode"
c = Client( address="polytope-test.ecmwf.int")

request = {
    "class": "d1",
    "dataset": "on-demand-extremes-dt",
    "expver": "aagq",
    "stream": "oper",
    "date": 20230820,
    "time": "1200",
    "type": "fc",
    "levtype": "ml",
    "georef": "u033tt",
    "param": 130,
    "step": 0,
    "timespan": "none",
    "feature": {
               "type": "verticalprofile",
               "points": [[48.8,1.8]],
               "axes": "levelist",
               "range": {"start": "1", "end": "90" }
    }
}

c.retrieve("deode", request, pointer=False)

we get

2026-06-15 13:46:06 - INFO - Sending request...
{'request': 'class: d1\n'
            'dataset: on-demand-extremes-dt\n'
            'date: 20230820\n'
            'expver: aagq\n'
            'feature:\n'
            '  axes: levelist\n'
            '  points:\n'
            '  - - 48.8\n'
            '    - 1.8\n'
            '  range:\n'
            "    end: '90'\n"
            "    start: '1'\n"
            '  type: verticalprofile\n'
            'georef: u033tt\n'
            'levtype: ml\n'
            'param: 130\n'
            'step: 0\n'
            'stream: oper\n'
            "time: '1200'\n"
            'timespan: none\n'
            'type: fc\n',
 'verb': 'retrieve'}
...
2026-06-15 13:46:08 - INFO - The current status of the request is 'processing'
2026-06-15 13:46:16 - WARNING - HTTPResponseError: Polytope error
Situation: trying to download data
Description: HTTP CLIENT ERROR (400)
URL: https://polytope-test.ecmwf.int:443/api/v1/requests/f974f834-ad99-43b7-9224-ec91b6095dfe
HTTP method: GET
Request header/body contents:
{'headers': {'Authorization': 'EmailKey **********1e9c'}, 'json': None}
Expected responses: 200, 202
Received response: CLIENT ERROR (400)
Details:
Request failed with error:
Matched datasource polytope-deode

Object of type Timedelta is not JSON serializable

What are the steps to reproduce the bug?

Run the example above.

Version

0.7.6

Platform (OS and architecture)

Red Hat Enterprise Linux release 10.2 (Coughlan)

Relevant log output

Accompanying data

No response

Organisation

SMHI/UrbanAIR

[awarde96]

Hey @uandrae, thanks. Yes this is a bug. It seems I updated all the other features to deal with timedelta but not vertical profile. I have a fix here ecmwf/covjsonkit#120, that I hope to get deployed in the next few days. I'll update the issue when its deployed.

[awarde96]

Hey @uandrae, the issue should now be fixed. Let me know if you have any other problems. Thanks for the report.