fix(target-allocator): use Downward API for OTELCOL_NAMESPACE so namespaceOverride works (#2218)

The TA pod's OTELCOL_NAMESPACE env was templated from
.Release.Namespace (or the optional collector_namespace value). When the
chart is installed into a different namespace via namespaceOverride,
every other resource lands in the override namespace, but the pod is
told to watch .Release.Namespace, so the collector watcher returns zero
pods and the allocator never assigns targets.

Source the value from the Downward API (metadata.namespace) so the pod
always sees its own namespace regardless of how the chart was installed
(helm install, subchart, helm template | kustomize, plain kubectl
apply, ArgoCD with destination override). This matches what the
operator's TA reconciler and the standalone manifest in
opentelemetry-operator already use.

The targetAllocator.config.collector_namespace value is preserved as an
explicit override that wins over the fieldRef, so deployments that
intentionally watch a different namespace from their own are
unaffected.

Bump chart to 0.128.1 and regenerate examples.

Author: sfc-gh-zeningchen

charts/opentelemetry-target-allocator/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v2
 name: opentelemetry-target-allocator
-version: 0.128.0
+version: 0.128.1
 description: OpenTelemetry Target Allocator Helm chart for Kubernetes
 type: application
 home: https://opentelemetry.io/

charts/opentelemetry-target-allocator/examples/collector-fleet/rendered/clusterRole.yaml

@@ -6,7 +6,7 @@ metadata:
   namespace: default
   name: example-opentelemetry-target-allocator-ta-clusterRole
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/collector-fleet/rendered/clusterRoleBinding.yaml

@@ -5,7 +5,7 @@ apiVersion: rbac.authorization.k8s.io/v1
 metadata:
   name: example-opentelemetry-target-allocator-ta-clusterRoleBinding
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/collector-fleet/rendered/configmap.yaml

@@ -6,7 +6,7 @@ metadata:
   name: example-opentelemetry-target-allocator-ta-configmap
   namespace: default
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/collector-fleet/rendered/deployment.yaml

@@ -6,7 +6,7 @@ metadata:
   namespace: default
   name: example-opentelemetry-target-allocator-ta
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"
@@ -21,9 +21,9 @@ spec:
   template:
     metadata:
       annotations:
-        checksum/config: ca42eb9ade6782b3d97ee14bb416001699f2fc9df0fe7011f079ee92f49a20ac
+        checksum/config: e37d0d540bfe4adb49aa51d7b7d4c5c028e1480520238a474d7a0afb3c18e874
       labels:
-        helm.sh/chart: opentelemetry-target-allocator-0.151.0
+        helm.sh/chart: opentelemetry-target-allocator-0.128.1
         app.kubernetes.io/managed-by: Helm
         app.kubernetes.io/part-of: opentelemetry-target-allocator
         app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/collector-fleet/rendered/serviceAccount.yaml

@@ -7,7 +7,7 @@ metadata:
   name: example-opentelemetry-target-allocator-ta
   namespace: default
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/consistent-hashing/rendered/clusterRole.yaml

@@ -6,7 +6,7 @@ metadata:
   namespace: default
   name: example-opentelemetry-target-allocator-ta-clusterRole
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/consistent-hashing/rendered/clusterRoleBinding.yaml

@@ -5,7 +5,7 @@ apiVersion: rbac.authorization.k8s.io/v1
 metadata:
   name: example-opentelemetry-target-allocator-ta-clusterRoleBinding
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/consistent-hashing/rendered/configmap.yaml

@@ -6,7 +6,7 @@ metadata:
   name: example-opentelemetry-target-allocator-ta-configmap
   namespace: default
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"

charts/opentelemetry-target-allocator/examples/consistent-hashing/rendered/deployment.yaml

@@ -6,7 +6,7 @@ metadata:
   namespace: default
   name: example-opentelemetry-target-allocator-ta
   labels:
-    helm.sh/chart: opentelemetry-target-allocator-0.151.0
+    helm.sh/chart: opentelemetry-target-allocator-0.128.1
     app.kubernetes.io/managed-by: Helm
     app.kubernetes.io/part-of: opentelemetry-target-allocator
     app.kubernetes.io/version: "0.151.0"
@@ -21,9 +21,9 @@ spec:
   template:
     metadata:
       annotations:
-        checksum/config: 9ff48203ed298ab5d9f8e4fc7724236d2b89b2445b3b05759f15588cd745af51
+        checksum/config: ca96982a57560c47f4f5666899beba95eabf7a0dfa218d4e7d7ea53586813531
       labels:
-        helm.sh/chart: opentelemetry-target-allocator-0.151.0
+        helm.sh/chart: opentelemetry-target-allocator-0.128.1
         app.kubernetes.io/managed-by: Helm
         app.kubernetes.io/part-of: opentelemetry-target-allocator
         app.kubernetes.io/version: "0.151.0"
@@ -46,7 +46,9 @@ spec:
               readOnly: true
           env: # Workaround for https://github.com/open-telemetry/opentelemetry-operator/pull/3976
             - name: OTELCOL_NAMESPACE
-              value: default
+              valueFrom:
+                fieldRef:
+                  fieldPath: metadata.namespace
           livenessProbe:
             httpGet:
               path: /livez