feat: label selectors for parent resource for GlueOperator (#88)

Signed-off-by: Attila Mészáros <[email protected]>

Author: csviri

docs/reference.md

@@ -82,8 +82,11 @@ The `DependentResource` implementation of JOSDK makes all kinds of optimizations
 ## [GlueOperator resource](https://github.com/csviri/kubernetes-glue-operator/releases/latest/download/glueoperators.glue-v1.yml)
 
 The specs of `GlueOperator` are almost identical to `Glue`, it just adds one additional attribute **`parent`**, 
-which has two sub-attributes: **`apiVersion`** and **`kind`**. This structure specifies the resource 
-types - usually but not necessarily custom resources - watched. 
+which has the following sub-attributes: 
+ - **`apiVersion`** and **`kind`** - specifies the resources to reconciler according to the spec. 
+   Targets are usually custom resources but not necessarily, it also works with built-in Kubernetes
+   resources.
+ - **`labelSelector`** - an optional label selector for the target resources
 
 See minimal `GlueOperator` [here](https://github.com/csviri/kubernetes-glue-operator/blob/main/src/test/resources/glueoperator/Templating.yaml).
 

src/main/java/io/csviri/operator/glue/customresource/operator/Parent.java

@@ -4,14 +4,15 @@ public class Parent {
 
   private String apiVersion;
   private String kind;
+  private String labelSelector;
+
+  public Parent() {}
 
   public Parent(String apiVersion, String kind) {
     this.apiVersion = apiVersion;
     this.kind = kind;
   }
 
-  public Parent() {}
-
   public String getApiVersion() {
     return apiVersion;
   }
@@ -29,4 +30,12 @@ public Parent setKind(String kind) {
     this.kind = kind;
     return this;
   }
+
+  public String getLabelSelector() {
+    return labelSelector;
+  }
+
+  public void setLabelSelector(String labelSelector) {
+    this.labelSelector = labelSelector;
+  }
 }

src/main/java/io/csviri/operator/glue/reconciler/operator/GlueOperatorReconciler.java

@@ -139,11 +139,17 @@ private InformerEventSource<GenericKubernetesResource, GlueOperator> getOrRegist
           .getResourceEventSourceFor(GenericKubernetesResource.class, gvk.toString());
       es.start();
     } catch (IllegalArgumentException e) {
-      es = new InformerEventSource<>(InformerConfiguration.from(gvk,
+      var configBuilder = InformerConfiguration.from(gvk,
           context.eventSourceRetriever().eventSourceContextForDynamicRegistration())
           .withSecondaryToPrimaryMapper(
-              resource -> Set.of(ResourceID.fromResource(glueOperator)))
-          .build(), context.eventSourceRetriever().eventSourceContextForDynamicRegistration());
+              resource -> Set.of(ResourceID.fromResource(glueOperator)));
+
+      if (spec.getParent().getLabelSelector() != null) {
+        configBuilder.withLabelSelector(spec.getParent().getLabelSelector());
+      }
+
+      es = new InformerEventSource<>(configBuilder.build(),
+          context.eventSourceRetriever().eventSourceContextForDynamicRegistration());
       context.eventSourceRetriever().dynamicallyRegisterEventSource(gvk.toString(), es);
     }
     return es;

src/test/java/io/csviri/operator/glue/GlueOperatorComplexLabelSelectorTest.java

@@ -54,7 +54,6 @@ void testGlueOperatorLabelSelector() {
           testCR.getKind()));
       assertThat(glue).isNull();
     });
-    delete(go);
   }
 
   public static class GlueOperatorComplexLabelSelectorTestProfile implements QuarkusTestProfile {

src/test/java/io/csviri/operator/glue/GlueOperatorLabelSelectorTest.java

@@ -63,7 +63,6 @@ void testGlueOperatorLabelSelector() {
           testCR.getKind()));
       assertThat(glue).isNull();
     });
-    delete(go);
   }
 
   public static class GlueOperatorLabelSelectorTestProfile implements QuarkusTestProfile {

src/test/java/io/csviri/operator/glue/GlueOperatorTest.java

@@ -27,8 +27,6 @@
 @QuarkusTest
 class GlueOperatorTest extends TestBase {
 
-
-
   @BeforeEach
   void applyCRD() {
     TestUtils.applyTestCrd(client, TestCustomResource.class, TestCustomResource2.class);
@@ -162,6 +160,33 @@ void nonUniqueNameTest() {
     });
   }
 
+  @Test
+  void parentWithLabelSelector() {
+    create(TestUtils
+        .loadResourceFlowOperator("/glueoperator/ParentLabelSelector.yaml"));
+
+    var cr = create(testCustomResource());
+    String name = cr.getMetadata().getName();
+
+    await().pollDelay(TestUtils.INITIAL_RECONCILE_WAIT_TIMEOUT).untilAsserted(() -> {
+      var cm1 = get(ConfigMap.class, name);
+      assertThat(cm1).isNull();
+    });
+
+    cr.getMetadata().getLabels().put("mylabel", "value");
+    update(cr);
+
+    await().untilAsserted(() -> {
+      var cm1 = get(ConfigMap.class, name);
+      assertThat(cm1).isNotNull();
+    });
+
+    delete(cr);
+    await().untilAsserted(() -> {
+      var cm1 = get(ConfigMap.class, name);
+      assertThat(cm1).isNull();
+    });
+  }
 
 
   GlueOperator testWorkflowOperator() {

src/test/resources/glueoperator/ParentLabelSelector.yaml

@@ -0,0 +1,18 @@
+apiVersion: io.csviri.operator.glue/v1beta1
+kind: GlueOperator
+metadata:
+  name: templating-sample
+spec:
+  parent:
+    apiVersion: io.csviri.operator.glue/v1
+    kind: TestCustomResource
+    labelSelector: "mylabel=value"
+  childResources:
+    - name: configMap1
+      resource:
+        apiVersion: v1
+        kind: ConfigMap
+        metadata:
+          name: "{parent.metadata.name}"
+        data:
+          key: "{parent.spec.value}"