chore: datadog unified service tagging

resources/emit-test-pod.yaml

@@ -2,6 +2,10 @@ apiVersion: v1
 kind: Pod
 metadata:
   name: ocaml-otel-test
+  labels:
+    tags.datadoghq.com/env: "poc"
+    tags.datadoghq.com/service: "t1"
+    tags.datadoghq.com/version: "2"
 spec:
   containers:
   - name: emit
@@ -14,6 +18,22 @@ spec:
         # This is picked up by the opentelemetry sdks
       - name: OTEL_EXPORTER_OTLP_ENDPOINT
         value: "http://$(HOST_IP):4318"
+      - name: POD_UID
+        valueFrom:
+          fieldRef:
+            fieldPath: metadata.uid
+      - name: DD_ENV
+        valueFrom:
+          fieldRef:
+            fieldPath: metadata.labels['tags.datadoghq.com/env']
+      - name: DD_SERVICE
+        valueFrom:
+          fieldRef:
+            fieldPath: metadata.labels['tags.datadoghq.com/service']
+      - name: DD_VERSION
+        valueFrom:
+          fieldRef:
+            fieldPath: metadata.labels['tags.datadoghq.com/version']
       - name: OTEL_RESOURCE_ATTRIBUTES
-        value: "service.name=t1,service.version=1,deployment.environment=poc"
+        value: "deployment.environment=$(DD_ENV),service.name=$(DD_SERVICE),service.version=$(DD_VERSION),k8s.pod.uid=$(POD_UID)"