fix: don't require selectors / metadata from existing resources

core/src/main/java/io/dekorate/AbstractKubernetesManifestGenerator.java

@@ -52,11 +52,13 @@
 import io.dekorate.kubernetes.decorator.AddJobDecorator;
 import io.dekorate.kubernetes.decorator.AddLabelDecorator;
 import io.dekorate.kubernetes.decorator.AddLivenessProbeDecorator;
+import io.dekorate.kubernetes.decorator.AddMetadataToTemplateDecorator;
 import io.dekorate.kubernetes.decorator.AddMountDecorator;
 import io.dekorate.kubernetes.decorator.AddPortDecorator;
 import io.dekorate.kubernetes.decorator.AddPvcVolumeDecorator;
 import io.dekorate.kubernetes.decorator.AddReadinessProbeDecorator;
 import io.dekorate.kubernetes.decorator.AddSecretVolumeDecorator;
+import io.dekorate.kubernetes.decorator.AddSelectorToDeploymentSpecDecorator;
 import io.dekorate.kubernetes.decorator.AddSidecarDecorator;
 import io.dekorate.kubernetes.decorator.AddStartupProbeDecorator;
 import io.dekorate.kubernetes.decorator.AddToSelectorDecorator;
@@ -124,7 +126,12 @@ protected void addDecorators(String group, C config) {
     //Metadata handling
     Labels.createLabels(config).forEach(l -> {
       resourceRegistry.decorate(group, new AddLabelDecorator(config.getName(), l));
+      // Ensure that metadata exists
+      resourceRegistry.decorate(group, new AddMetadataToTemplateDecorator());
+
       resourceRegistry.decorate(group, new AddToSelectorDecorator(config.getName(), l.getKey(), l.getValue()));
+      // Selectors have some additional requirements
+      resourceRegistry.decorate(group, new AddSelectorToDeploymentSpecDecorator());
     });
 
     for (Annotation annotation : config.getAnnotations()) {

core/src/main/java/io/dekorate/kubernetes/decorator/AddMetadataToTemplateDecorator.java

@@ -0,0 +1,19 @@
+package io.dekorate.kubernetes.decorator;
+
+import io.fabric8.kubernetes.api.model.ObjectMeta;
+import io.fabric8.kubernetes.api.model.PodTemplateSpecFluent;
+
+public class AddMetadataToTemplateDecorator extends NamedResourceDecorator<PodTemplateSpecFluent<?>> {
+
+  @Override
+  public void andThenVisit(PodTemplateSpecFluent<?> item, ObjectMeta resourceMeta) {
+    if (!item.hasMetadata()) {
+      item.withNewMetadata().endMetadata();
+    }
+  }
+
+  @Override
+  public Class<? extends Decorator>[] before() {
+    return new Class[] { AddLabelDecorator.class, RemoveLabelDecorator.class };
+  }
+}

core/src/main/java/io/dekorate/kubernetes/decorator/AddSelectorToDeploymentSpecDecorator.java

@@ -0,0 +1,23 @@
+package io.dekorate.kubernetes.decorator;
+
+import java.util.HashMap;
+
+import io.fabric8.kubernetes.api.model.ObjectMeta;
+import io.fabric8.kubernetes.api.model.apps.DeploymentSpecFluent;
+
+public class AddSelectorToDeploymentSpecDecorator extends NamedResourceDecorator<DeploymentSpecFluent<?>> {
+
+  @Override
+  public void andThenVisit(DeploymentSpecFluent<?> item, ObjectMeta resourceMeta) {
+    if (!item.hasSelector()) {
+      item.withNewSelector()
+          .withMatchLabels(new HashMap<>())
+          .endSelector();
+    }
+  }
+
+  @Override
+  public Class<? extends Decorator>[] before() {
+    return new Class[] { AddToSelectorDecorator.class };
+  }
+}

core/src/main/java/io/dekorate/kubernetes/decorator/AddToSelectorDecorator.java

@@ -61,8 +61,8 @@ public void andThenVisit(VisitableBuilder item, ObjectMeta resourceMeta) {
   }
 
   @Override
-  public Class<? extends Decorator>[] before() {
-    return new Class[] { AddToSelectorDecorator.class };
+  public Class<? extends Decorator>[] after() {
+    return new Class[] { AddSelectorToDeploymentSpecDecorator.class };
   }
 
 }

core/src/main/java/io/dekorate/kubernetes/decorator/DeploymentResourceFactory.java

@@ -15,14 +15,11 @@
  */
 package io.dekorate.kubernetes.decorator;
 
-import java.util.HashMap;
-
 import io.dekorate.AbstractKubernetesManifestGenerator;
 import io.dekorate.ResourceFactory;
 import io.dekorate.kubernetes.config.BaseConfig;
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.fabric8.kubernetes.api.model.PodSpecBuilder;
-import io.fabric8.kubernetes.api.model.PodTemplateSpecBuilder;
 import io.fabric8.kubernetes.api.model.apps.DeploymentBuilder;
 
 public class DeploymentResourceFactory implements ResourceFactory {
@@ -42,12 +39,9 @@ public HasMetadata create(AbstractKubernetesManifestGenerator<?> generator, Base
         .endMetadata()
         .withNewSpec()
         .withReplicas(1)
-        .withNewSelector() //We need to have at least an empty selector so that the decorator can work with it.
-        .withMatchLabels(new HashMap<String, String>())
-        .endSelector()
-        .withTemplate(new PodTemplateSpecBuilder()
-            .withSpec(new PodSpecBuilder().build())
-            .withNewMetadata().endMetadata().build())
+        .withNewTemplate()
+        .withSpec(new PodSpecBuilder().build())
+        .endTemplate()
         .endSpec().build();
   }
 }

examples/pom.xml

@@ -3,7 +3,7 @@
   <parent>
     <artifactId>dekorate-project</artifactId>
     <groupId>io.dekorate</groupId>
-    <version>3.4-SNAPSHOT</version>
+    <version>3.5-SNAPSHOT</version>
   </parent>
   <modelVersion>4.0.0</modelVersion>
 

tests/pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.dekorate</groupId>
         <artifactId>dekorate-project</artifactId>
-        <version>3.4-SNAPSHOT</version>
+        <version>3.5-SNAPSHOT</version>
         <relativePath>..</relativePath>
     </parent>
     <modelVersion>4.0.0</modelVersion>