feat(health): Add healthCheck for CRD DatadogMetric (#23464)

Signed-off-by: Nicolas Richard <nicolas.richard@chime.com>

resource_customizations/datadoghq.com/DatadogMetric/health.lua

@@ -0,0 +1,32 @@
+-- Reference CRD can be found here:
+-- https://github.com/DataDog/helm-charts/blob/main/charts/datadog-crds/templates/datadoghq.com_datadogmetrics_v1.yaml
+
+hs = {}
+if obj.status ~= nil and obj.status.conditions ~= nil then
+  for i, condition in ipairs(obj.status.conditions) do
+    -- Check for the "Error: True" condition first
+    if condition.type == "Error" and condition.status == "True" then
+      hs.status = "Degraded"
+      local reason = condition.reason or ""
+      local message = condition.message or "DatadogMetric reported an error"
+      if reason ~= "" then
+        hs.message = reason .. ": " .. message
+      else
+        hs.message = message
+      end
+      return hs
+    end
+  end
+  for i, condition in ipairs(obj.status.conditions) do
+    -- Check for the "Valid: False" condition
+    if condition.type == "Valid" and condition.status == "False" then
+      hs.status = "Degraded"
+      hs.message = condition.message or "DatadogMetric is not valid"
+      return hs
+    end
+  end
+end
+-- If no "Degraded" conditions are found, default to Healthy
+hs.status = "Healthy"
+hs.message = "DatadogMetric is healthy"
+return hs

resource_customizations/datadoghq.com/DatadogMetric/health_test.yaml

@@ -0,0 +1,13 @@
+tests:
+  - healthStatus:
+      status: Degraded
+      message: "Unable to fetch data from Datadog: Processing data from API failed, reason: no serie was found for this query in API Response, check Cluster Agent logs for QueryIndex errors, query was: max:foo.bar.metric"
+    inputPath: testdata/degraded_error.yaml
+  - healthStatus:
+      status: Degraded
+      message: "The metric query is invalid"
+    inputPath: testdata/degraded_invalid.yaml
+  - healthStatus:
+      status: Healthy
+      message: "DatadogMetric is healthy"
+    inputPath: testdata/healthy.yaml

resource_customizations/datadoghq.com/DatadogMetric/testdata/degraded_error.yaml

@@ -0,0 +1,24 @@
+apiVersion: datadoghq.com/v1alpha1
+kind: DatadogMetric
+metadata:
+  name: foo-bar-metric
+  namespace: foo-namespace
+status:
+  autoscalerReferences:
+    - hpa:foo-namespace/foo-bar-hpa
+  conditions:
+    - lastTransitionTime: "2025-02-05T00:03:00Z"
+      lastUpdateTime: "2025-06-17T17:49:45Z"
+      status: "True"
+      type: Active
+    - lastTransitionTime: "2025-02-05T00:03:00Z"
+      lastUpdateTime: "2025-06-17T17:49:45Z"
+      status: "False"
+      type: Valid
+    - lastTransitionTime: "2025-02-05T00:03:30Z"
+      lastUpdateTime: "2025-06-17T17:49:45Z"
+      message: "Processing data from API failed, reason: no serie was found for this query in API Response, check Cluster Agent logs for QueryIndex errors, query was: max:foo.bar.metric"
+      reason: Unable to fetch data from Datadog
+      status: "True"
+      type: Error
+  currentValue: 0

resource_customizations/datadoghq.com/DatadogMetric/testdata/degraded_invalid.yaml

@@ -0,0 +1,19 @@
+apiVersion: datadoghq.com/v1alpha1
+kind: DatadogMetric
+metadata:
+  name: foo-bar-metric-invalid
+  namespace: foo-namespace
+status:
+  autoscalerReferences:
+    - hpa:foo-namespace/foo-bar-hpa
+  conditions:
+    - lastTransitionTime: "2025-02-05T00:03:00Z"
+      lastUpdateTime: "2025-06-17T17:49:45Z"
+      status: "True"
+      type: Active
+    - lastTransitionTime: "2025-02-05T00:03:00Z"
+      lastUpdateTime: "2025-06-17T17:49:45Z"
+      status: "False"
+      type: Valid
+      message: "The metric query is invalid"
+  currentValue: 0 

resource_customizations/datadoghq.com/DatadogMetric/testdata/healthy.yaml

@@ -0,0 +1,25 @@
+apiVersion: datadoghq.com/v1alpha1
+kind: DatadogMetric
+metadata:
+  name: foo-bar-metric
+  namespace: foo-namespace
+status:
+  autoscalerReferences:
+    - hpa:foo-namespace/foo-bar-hpa
+  conditions:
+    - lastTransitionTime: "2025-04-23T18:40:58Z"
+      lastUpdateTime: "2025-06-17T20:45:05Z"
+      status: "True"
+      type: Active
+    - lastTransitionTime: "2025-06-16T14:07:12Z"
+      lastUpdateTime: "2025-06-17T20:45:05Z"
+      status: "True"
+      type: Valid
+    - lastUpdateTime: "2025-06-17T20:44:30Z"
+      status: "True"
+      type: Updated
+    - lastTransitionTime: "2025-06-16T14:07:12Z"
+      lastUpdateTime: "2025-06-17T20:45:05Z"
+      status: "False"
+      type: Error
+  currentValue: 0