From a8bd29f78c3707065856d5065f9d2cac1194e6ec Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Thu, 7 May 2026 12:15:26 -0500
Subject: [PATCH] fix(logging): log silently dropped parse failures in grib
 extractor/wgrib2

- extractor: log warning when point falls outside Lambert grid bounds
- wgrib2: log warning when inventory lines are unparseable
- hrrr_client: optimize wgrib2_match_pattern with uniq_by + map_join
- gefs_client: same optimization
---
 lib/microwaveprop/weather/gefs_client.ex     | 2 +-
 lib/microwaveprop/weather/grib2/extractor.ex | 3 +++
 lib/microwaveprop/weather/grib2/wgrib2.ex    | 1 +
 lib/microwaveprop/weather/hrrr_client.ex     | 2 +-
 4 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/microwaveprop/weather/gefs_client.ex b/lib/microwaveprop/weather/gefs_client.ex
index 6393e913..4a034511 100644
--- a/lib/microwaveprop/weather/gefs_client.ex
+++ b/lib/microwaveprop/weather/gefs_client.ex
@@ -232,7 +232,7 @@ defmodule Microwaveprop.Weather.GefsClient do
   end
 
   defp wgrib2_match_pattern do
-    vars = @surface_messages |> Enum.map(& &1.var) |> Enum.uniq() |> Enum.join("|")
+    vars = @surface_messages |> Enum.uniq_by(& &1.var) |> Enum.map_join("|", & &1.var)
     ":(#{vars}):"
   end
 
diff --git a/lib/microwaveprop/weather/grib2/extractor.ex b/lib/microwaveprop/weather/grib2/extractor.ex
index f6be53e3..8c5bd555 100644
--- a/lib/microwaveprop/weather/grib2/extractor.ex
+++ b/lib/microwaveprop/weather/grib2/extractor.ex
@@ -6,6 +6,8 @@ defmodule Microwaveprop.Weather.Grib2.Extractor do
   alias Microwaveprop.Weather.Grib2.Section
   alias Microwaveprop.Weather.Grib2.SimplePacking
 
+  require Logger
+
   @doc """
   Extract weather values from a GRIB2 binary blob at the given lat/lon.
 
@@ -129,6 +131,7 @@ defmodule Microwaveprop.Weather.Grib2.Extractor do
           [{point, linear_index({i, j}, grid.nx, grid.scan_mode)}]
 
         {:error, :outside_grid} ->
+          Logger.warning("Extractor: point #{lat},#{lon} outside Lambert grid bounds")
           []
       end
     end)
diff --git a/lib/microwaveprop/weather/grib2/wgrib2.ex b/lib/microwaveprop/weather/grib2/wgrib2.ex
index e6650ae0..6b7a1e3a 100644
--- a/lib/microwaveprop/weather/grib2/wgrib2.ex
+++ b/lib/microwaveprop/weather/grib2/wgrib2.ex
@@ -309,6 +309,7 @@ defmodule Microwaveprop.Weather.Grib2.Wgrib2 do
           [%{var: var, level: level, datetime: parse_wgrib2_date(date)}]
 
         _ ->
+          Logger.warning("wgrib2: unparseable inventory line: #{String.slice(line, 0, 120)}")
           []
       end
     end)
diff --git a/lib/microwaveprop/weather/hrrr_client.ex b/lib/microwaveprop/weather/hrrr_client.ex
index 04986579..fd63ddc3 100644
--- a/lib/microwaveprop/weather/hrrr_client.ex
+++ b/lib/microwaveprop/weather/hrrr_client.ex
@@ -425,7 +425,7 @@ defmodule Microwaveprop.Weather.HrrrClient do
   end
 
   defp wgrib2_match_pattern(wanted) do
-    vars = wanted |> Enum.map(& &1.var) |> Enum.uniq() |> Enum.join("|")
+    vars = wanted |> Enum.uniq_by(& &1.var) |> Enum.map_join("|", & &1.var)
     ":(#{vars}):"
   end