feat(esphome): add observability for heating-sensor

kubernetes/talos-flux/apps/home-automation/esphome/flux-sync.yaml

@@ -15,3 +15,21 @@ spec:
     kind: GitRepository
     name: home-ops
   wait: true
+
+---
+# yaml-language-server: $schema=https://raw.githubusercontent.com/fluxcd-community/flux2-schemas/main/kustomization-kustomize-v1beta2.json
+apiVersion: kustomize.toolkit.fluxcd.io/v1beta2
+kind: Kustomization
+metadata:
+  name: apps-esphome-obervability
+  namespace: flux-system
+  labels:
+    substitution.flux.home.arpa/enabled: "true"
+spec:
+  interval: 10m
+  path: ./kubernetes/talos-flux/apps/home-automation/esphome/obervability
+  prune: true
+  sourceRef:
+    kind: GitRepository
+    name: home-ops
+  wait: true

kubernetes/talos-flux/apps/home-automation/esphome/observability/kustomization.yaml

@@ -0,0 +1,12 @@
+---
+# yaml-language-server: $schema=https://json.schemastore.org/kustomization
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+namespace: home-automation
+resources:
+  - prometheus-rule.yaml
+labels:
+  - pairs:
+      app.kubernetes.io/name: esphome-observability
+      app.kubernetes.io/instance: esphome-observability
+      app.kubernetes.io/part-of: esphome

kubernetes/talos-flux/apps/home-automation/esphome/observability/prometheus-rule.yaml

@@ -0,0 +1,37 @@
+---
+# yaml-language-server: $schema=https://raw.githubusercontent.com/datreeio/CRDs-catalog/main/monitoring.coreos.com/prometheusrule_v1.json
+apiVersion: monitoring.coreos.com/v1
+kind: PrometheusRule
+metadata:
+  name: esphome-alerts
+spec:
+  groups:
+    - name: esphome.sensor-heating.rules
+      rules:
+        - alert: ESPHomeHeatingSensorAbsent
+          annotations:
+            description: ESPHome sensor-heating has disappeared from Prometheus target discovery
+            summary: ESPHome sensor-heating has disappeared from Prometheus target discovery
+          expr: |-
+            absent(up{device="sensor-heating"})
+          for: 15m
+          labels:
+            severity: warning
+        - alert: ESPHomeHeatingSensorHighTemperature
+          annotations:
+            description: ESPHome sensor-heating temperature is too high
+            summary: ESPHome sensor-heating high temp
+          expr: |-
+            esphome_sensor_value{device="sensor-heating", name="Sensor Heating Temperature Flow Upstairs"} > 30
+          for: 10m
+          labels:
+            severity: warning
+        - alert: ESPHomeHeatingSensorLowTemperature
+          annotations:
+            description: ESPHome sensor-heating temperature is low
+            summary: ESPHome sensor-heating low temp
+          expr: |-
+            esphome_sensor_value{device="sensor-heating", name="Sensor Heating Temperature Flow Upstairs"} < 22
+          for: 10m
+          labels:
+            severity: warning