feat(sensors): numeric -n mode + lmsensors_n extend for HA SNMP migration [#618]

dcinfra/sensors/temper/deploy.sh

@@ -127,6 +127,7 @@ sed -i 's/^agentaddress/#agentaddress/' "$SNMPD_CONF"
         echo "rocommunity $COMMUNITY $src"
     done
     echo "extend lmsensors $WRAP_DST"
+    echo "extend lmsensors_n $WRAP_DST -n"
     echo "$MARK_END"
 } >>"$SNMPD_CONF"
 log "agentaddress: $AGENT_ADDRS"

dcinfra/sensors/temper/lmsensors-extend.sh

@@ -37,6 +37,39 @@ format_block() {
 }
 
 # True when a TEMPer USB dongle (0c45:7401) is attached and the venv exists.
+
+# Numeric mode: print ONE Celsius float for snmpd extend lmsensors_n [#618].
+# Preference: TEMPer external > TEMPer internal > first native/sysfs temp
+# reading. Consumed by HA's SNMP config-entry integration (device_class
+# temperature; HA renders C in the instance display unit).
+numeric_pick() {
+    local internal="${1:-}" external="${2:-}" native="${3:-}" pick
+    local num_re='^-?[0-9]+(\.[0-9]+)?$'
+    for pick in "$external" "$internal"; do
+        pick="${pick#+}"
+        [[ "$pick" =~ $num_re ]] && { printf '%s\n' "$pick"; return 0; }
+    done
+    if [[ -n "$native" ]]; then
+        pick="$(grep -oE '\-?[0-9]+(\.[0-9]+)?' <<<"$native" | head -1)"
+        [[ "$pick" =~ $num_re ]] && { printf '%s\n' "$pick"; return 0; }
+    fi
+    return 1
+}
+
+numeric_main() {
+    local internal external line
+    if has_temper_probe; then
+        if read -r internal external <<<"$(read_temper 2>/dev/null)"; then
+            numeric_pick "${internal:-}" "${external:-}" "" && return 0
+        fi
+    fi
+    line="$(run_native_sensors | grep -m1 '°C')"
+    [[ -n "$line" ]] && numeric_pick "" "" "$line" && return 0
+    line="$(read_sysfs_thermal 2>/dev/null | head -1 | awk '{printf "+%.1f°C", $2/1000}')"
+    [[ -n "$line" ]] && numeric_pick "" "" "$line" && return 0
+    echo "error: numeric mode found no sensor source" >&2
+    return 1
+}
 has_temper_probe() {
     command -v lsusb >/dev/null 2>&1 || return 1
     [[ -x "$VENV_PY" ]] || return 1
@@ -130,5 +163,5 @@ main() {
 }
 
 if [[ "${BASH_SOURCE[0]}" == "$0" ]]; then
-    main
+    if [[ "${1:-}" == "-n" ]]; then numeric_main; else main; fi
 fi

tests/unit/lmsensors-numeric.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+# Unit tests for lmsensors-extend.sh -n numeric mode [#618]
+set -euo pipefail
+
+PROJECT_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+SCRIPT="$PROJECT_ROOT/dcinfra/sensors/temper/lmsensors-extend.sh"
+
+failed=0
+if [[ -f "$SCRIPT" ]] && (source "$SCRIPT"); then
+    echo "✅ script exists + sources cleanly"
+else
+    echo "❌ script missing or fails to source: $SCRIPT"
+    exit 1
+fi
+# shellcheck disable=SC1091
+source "$SCRIPT"
+
+# numeric_pick: TEMPer external > TEMPer internal > first native/sysfs value
+test_numeric_prefers_external() {
+    if [[ "$(numeric_pick "22.5" "18.2" "" )" == "18.2" ]]; then
+        echo "✅ numeric_pick prefers external probe"
+    else
+        echo "❌ numeric_pick external preference broken"
+        ((++failed))
+    fi
+}
+
+test_numeric_falls_back_internal() {
+    if [[ "$(numeric_pick "22.5" "" "")" == "22.5" ]]; then
+        echo "✅ numeric_pick falls back to internal"
+    else
+        echo "❌ numeric_pick internal fallback broken"
+        ((++failed))
+    fi
+}
+
+test_numeric_uses_first_line_value() {
+    if [[ "$(numeric_pick "" "" "+27.5°C")" == "27.5" ]]; then
+        echo "✅ numeric_pick parses first native temp"
+    else
+        echo "❌ numeric_pick native parse broken: got '$(numeric_pick "" "" "+27.5°C")'"
+        ((++failed))
+    fi
+}
+
+test_numeric_empty_is_error() {
+    if numeric_pick "" "" "" >/dev/null 2>&1; then
+        echo "❌ numeric_pick should fail on no data"
+        ((++failed))
+    else
+        echo "✅ numeric_pick errors on no data"
+    fi
+}
+
+test_numeric_prefers_external
+test_numeric_falls_back_internal
+test_numeric_uses_first_line_value
+test_numeric_empty_is_error
+
+if ((failed > 0)); then
+    echo "❌ $failed numeric-mode test(s) failed"
+    exit 1
+fi
+echo "✅ all numeric-mode tests passed"