Failed to run AIRMET example—potentially related to the retirement of TAC AIRMETs & transition to G-AIRMETs?

[kpcftsz]

In September '24, a service change notice was published by the NWS outlining efforts to transition away from TAC AIRMETs in favor of G-AIRMETs: https://www.weather.gov/media/notification/pdf_2023_24/scn24-92tac_airmet_retirement.pdf
G-AIRMETs may come in the form of XML. Info on the format is available here:
https://www.weather.gov/media/notification/ref/pdd_xml_g-airmet.pdf

Below is what I got when attempting to run an example from the AirSigManager documentation. I'm guessing this is related to the changes above affecting retrieval of WA..../WS.... text in particular.

Traceback (most recent call last):
  File "test.py", line 7, in <module>
    manager.update()
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 167, in update
    return aio.run(self.async_update(timeout, disable_post))
  File "/usr/lib/python3.8/asyncio/runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "/usr/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
    return future.result()
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 188, in async_update
    exceptions.exception_intercept(exc, raw={"report": report})
  File "/usr/local/lib/python3.8/dist-packages/avwx/exceptions.py", line 8, in exception_intercept
    raise exception
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 184, in async_update
    if obj := AirSigmet.from_report(report):
  File "/usr/local/lib/python3.8/dist-packages/avwx/base.py", line 72, in from_report
    obj.parse(report, issued=issued)
  File "/usr/local/lib/python3.8/dist-packages/avwx/base.py", line 85, in parse
    self._post_parse()
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 87, in _post_parse
    self.data, self.units = parse(self.raw, self.issued)
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 668, in parse
    data, bulletin, issuer, time, correction = _header(_parse_prep(sanitized))
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 258, in _header
    bulletin = _bulletin(data[0])
  File "/usr/local/lib/python3.8/dist-packages/avwx/current/airsigmet.py", line 251, in _bulletin
    type=Code(repr=type_key, value=BULLETIN_TYPES[type_key]), # <- 
KeyError: 'TS'

[devdupont]

That is part of what is happening. It's understandable for a text parser to break when there are major changes.

As of right now, the NOAA G-AIRMET data only comes in XML formatting and lacks a raw text version that usually accompanies the CSV counterparts. In that case, it's mostly a matter of converting the NOAA formatting to avwx-compatible objects and including either an empty string or stringified data for the raw report.

The other problem is that the G-AIRMETs in NOAA only cover CONUS. They split the non-US reports into a different feed. The manager you're using in that example combines the two sources. The non-US reports still use TAC formatting, so both formatting types will have to coexist. Shouldn't be a big deal since METARs also have multiple formats.

CONUS G-AIRMETs: https://aviationweather.gov/data/cache/gairmets.cache.xml
Old AIRSIGMETs: https://aviationweather.gov/data/cache/airsigmets.cache.csv
Non-US AIRSIGMETs: https://aviationweather.gov/api/data/isigmet

[devdupont]

A potentially dubious but plausible solution to the "raw" (or more likely "sanitized") report problem is to retro-generate the text from the encoded XML data.