Fix name label propagation for TA selectors (open-telemetry#2632)

* propagate name label to selector

* add propagation test to e2e-targetallocator

* add chlog

* restore comments

* add test to chainsaw

Author: changexd

.chloggen/fix-2598.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. operator, target allocator, github action)
+component: operator
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: propagate otel name label down to selector of ta resources
+
+# One or more tracking issues related to the change
+issues: [2598]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

internal/manifests/targetallocator/labels.go

@@ -28,8 +28,14 @@ func Labels(instance v1beta1.OpenTelemetryCollector, name string) map[string]str
 // SelectorLabels return the selector labels for Target Allocator Pods.
 func SelectorLabels(instance v1beta1.OpenTelemetryCollector) map[string]string {
 	selectorLabels := manifestutils.SelectorLabels(instance.ObjectMeta, ComponentOpenTelemetryTargetAllocator)
+
 	// TargetAllocator uses the name label as well for selection
 	// This is inconsistent with the Collector, but changing is a somewhat painful breaking change
-	selectorLabels["app.kubernetes.io/name"] = naming.TargetAllocator(instance.Name)
+	// Don't override the app name if it already exists
+	if name, ok := instance.ObjectMeta.Labels["app.kubernetes.io/name"]; ok {
+		selectorLabels["app.kubernetes.io/name"] = name
+	} else {
+		selectorLabels["app.kubernetes.io/name"] = naming.TargetAllocator(instance.Name)
+	}
 	return selectorLabels
 }

internal/manifests/targetallocator/labels_test.go

@@ -61,11 +61,13 @@ func TestLabelsPropagateDown(t *testing.T) {
 
 	// test
 	labels := Labels(otelcol, name)
+	selectorLabels := SelectorLabels(otelcol)
 
 	// verify
 	assert.Len(t, labels, 7)
 	assert.Equal(t, "mycomponent", labels["myapp"])
 	assert.Equal(t, "test", labels["app.kubernetes.io/name"])
+	assert.Equal(t, "test", selectorLabels["app.kubernetes.io/name"])
 }
 
 func TestSelectorLabels(t *testing.T) {

tests/e2e-targetallocator/targetallocator-features/02-assert.yaml

@@ -0,0 +1,17 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: stateful-targetallocator
+  labels:
+    app.kubernetes.io/name: test
+spec:
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: test
+  template:
+    metadata:
+      labels:
+        app.kubernetes.io/name: test
+status:
+  replicas: 1
+  readyReplicas: 1

tests/e2e-targetallocator/targetallocator-features/02-install.yaml

@@ -0,0 +1,7 @@
+apiVersion: opentelemetry.io/v1alpha1
+kind: OpenTelemetryCollector
+metadata:
+  name: stateful
+  labels:
+    app.kubernetes.io/name: test
+  

tests/e2e-targetallocator/targetallocator-features/chainsaw-test.yaml

@@ -39,3 +39,9 @@ spec:
         duration: 35s
     - assert:
         file: 01-assert.yaml
+  - name: step-02
+    try:
+    - apply:
+        file: 02-install.yaml
+    - assert:
+        file: 02-assert.yaml