The /path calculator showed "0 / 9 HRRR points" in production despite
the on-disk profile store being current. Root cause: profile_from_cell/2
treated the cell's :profile key as a wrapper sub-map and called
Map.put_new on it — but the :profile key actually holds the vertical
pressure-level LIST. Every point sample crashed with BadMapError, the
crash propagated as {:exit, _} through Task.async_stream, and the
consumer silently dropped all 9 results.
Fix: stop wrapping. Cells are already flat HrrrProfile-shaped maps;
just stamp lat/lon (from the caller, since cells don't carry their
own coords — those are the map key) and valid_time onto the cell.
Audit + log every other async error path so the next silent failure
isn't invisible:
- PathLive HRRR point lookup
- Propagation.point_forecast per-hour reads
- Viewshed ray crashes
- IemClient ASOS network fetches
- RtmaClient range-download tasks
- Recalibrator factor-vector batches (positive + negative samples)
- MapLive forecast preload tasks
- RoverLive station resolution
LiveViews already had handle_async/3 exit clauses with logging. The
gap was always in Task.async_stream consumers that wrote {:exit, _} -> []
without surfacing the reason.
Add the rule to CLAUDE.md and project memory so this never repeats.
Also fix a pre-existing skewt_svg.ex compiler warning where
@critical_label_min_dy was used before being defined.
Adds spans to 15 previously-unmeasured hot paths so every question we
might ask while tuning has a histogram to answer it:
External I/O:
- iem.fetch_iemre (gridded weather reanalysis)
- mrms.list_latest / mrms.download (precip radar)
- rtma.fetch_observation
- ncei.fetch_metar (historical 5-min METAR backfill)
- solar.fetch_indices (GFZ solar indices)
- swpc.fetch (SWPC Kp/F10.7/X-ray)
- giro.fetch (ionosonde)
- qrz.request, geocoder.geocode (callsign enrichment)
- srtm.download_tile (terrain tile download + gunzip)
- hrrr.download_grib_ranges (parallel byte-range fetch phase)
Subprocess:
- wgrib2.extract_grid / extract_grid_from_file / extract_grid_from_file_mapped
LiveView hot paths:
- propagation.scores_at (map score fetch + cache hit/miss counter)
- propagation.point_forecast (sparkline)
- propagation.point_detail (click-to-inspect)
- propagation.daily_outlook_at (/map outlook strip)
Worker-level end-to-end:
- worker.terrain_profile
- worker.mechanism_classify
- worker.mrms_fetch
Each event is registered in Microwaveprop.PromEx.InstrumentPlugin as
a Prometheus histogram (default / long buckets as appropriate) plus
a counter for the scores_at cache hit/miss ratio. Prometheus at
10.0.15.25 will start seeing the new series on the next scrape after
deploy.
RtmaClient was the only weather client without a Req.Test plug seam —
added the standard req_options() helper matching NarrClient/HrrrClient/
etc. so its HTTP calls can be stubbed in test.
17 characterization tests: URL construction, idx fetch 404/503, hour
truncation, malformed idx, range-GET error propagation, worker's
existing-row short-circuit, client-error propagation. GRIB2 byte
parsing paths deferred to the wgrib2 coverage task.
