Domain status patching switching behavior

Author: rjeberhard

operator/src/main/java/oracle/kubernetes/operator/Main.java

@@ -105,6 +105,23 @@ public class Main {
   private static String principal;
   private static KubernetesVersion version = null;
 
+  /* MARKER-2.6.0-ONLY */
+  // This is needed only for 2.6.0 -- do not forward port to 3.x
+  // In 3.0.0, we are switching the CRD to enable the domain status endpoint. This means that all updates to the
+  // domain status must be made against that REST endpoint and that (according to the K8s doc) attempts to
+  // update the domain status through the normal endpoint will be ignored.
+  //
+  // However, for Kubernetes versions less than 1.16, the 2.6.0 CRD needs to remain
+  // unchanged for interoperability with 2.5.0. Therefore, 2.6.0 will detect if a 3.x operator has changed the
+  // CRD and modify its behavior. This provides an upgrade path from 2.x to 3.x, which is that all operators
+  // must be updated to 2.6.0 before a 3.0.0 operator is introduced to the cluster, but if this strategy is used
+  // then 2.5.0 is compatible with 2.6.0 and 2.6.0 is compatible with 3.0.0.
+  //
+  // When running on 1.16 and above, 2.6.0 will also create a CRD with the status endpoint enabled since there is
+  // no need to be compatible with 2.5.0.
+  public static AtomicBoolean useDomainStatusEndpoint = new AtomicBoolean(false);
+  /* END-2.6.0-ONLY */
+
   static {
     try {
       // suppress System.err since we catch all necessary output with Logger

operator/src/main/java/oracle/kubernetes/operator/helpers/CrdHelper.java

@@ -39,6 +39,7 @@
 import io.kubernetes.client.util.Yaml;
 import oracle.kubernetes.json.SchemaGenerator;
 import oracle.kubernetes.operator.KubernetesConstants;
+import oracle.kubernetes.operator.Main;
 import oracle.kubernetes.operator.calls.CallResponse;
 import oracle.kubernetes.operator.logging.LoggingFacade;
 import oracle.kubernetes.operator.logging.LoggingFactory;
@@ -240,7 +241,11 @@ static V1CustomResourceSubresources createSubresources() {
 
     static V1beta1CustomResourceSubresources createBetaSubresources() {
       return new V1beta1CustomResourceSubresources()
-          .status(new HashMap<String, String>()) // this just needs an empty object to enable status subresource
+          /* MARKER-2.6.0-ONLY */
+          // for 2.6.0 we will not enable the status subresource for the beta version of CRD
+          // the 3.0.0 operator will enable this subresource so 2.6.0 will still check the actual CRD
+          // .status(new HashMap<String, String>()) // this just needs an empty object to enable status subresource
+          /* END-2.6.0-ONLY */
           .scale(
               new V1beta1CustomResourceSubresourceScale()
                   .specReplicasPath(".spec.replicas")
@@ -251,6 +256,9 @@ static List<V1CustomResourceDefinitionVersion> getCrdVersions() {
       Map<String, String> schemas = schemaReader.loadFilesFromClasspath();
       List<V1CustomResourceDefinitionVersion> versions = schemas.entrySet().stream()
           .sorted(Comparator.comparing(Map.Entry::getKey))
+          /* MARKER-2.6.0-ONLY */
+          .filter(entry -> !KubernetesConstants.DOMAIN_VERSION.equals(getVersionFromCrdSchemaFileName(entry.getKey())))
+          /* END-2.6.0-ONLY */
           .map(entry -> new V1CustomResourceDefinitionVersion()
               .name(getVersionFromCrdSchemaFileName(entry.getKey()))
               .schema(getValidationFromCrdSchemaFile(entry.getValue()))
@@ -274,6 +282,9 @@ static List<V1beta1CustomResourceDefinitionVersion> getBetaCrdVersions() {
       Map<String, String> schemas = schemaReader.loadFilesFromClasspath();
       List<V1beta1CustomResourceDefinitionVersion> versions = schemas.entrySet().stream()
           .sorted(Comparator.comparing(Map.Entry::getKey))
+          /* MARKER-2.6.0-ONLY */
+          .filter(entry -> !KubernetesConstants.DOMAIN_VERSION.equals(getVersionFromCrdSchemaFileName(entry.getKey())))
+          /* END-2.6.0-ONLY */
           .map(entry -> new V1beta1CustomResourceDefinitionVersion()
               .name(getVersionFromCrdSchemaFileName(entry.getKey()))
               .served(true)
@@ -353,7 +364,7 @@ static SchemaGenerator createSchemaGenerator() {
 
     Step verifyCrd(Step next) {
       return new CallBuilder().readCustomResourceDefinitionAsync(
-              model.getMetadata().getName(), createReadResponseStep(next));
+          model.getMetadata().getName(), createReadResponseStep(next));
     }
 
     ResponseStep<V1CustomResourceDefinition> createReadResponseStep(Step next) {
@@ -371,7 +382,7 @@ ResponseStep<V1beta1CustomResourceDefinition> createBetaReadResponseStep(Step ne
 
     Step createCrd(Step next) {
       return new CallBuilder().createCustomResourceDefinitionAsync(
-              model, createCreateResponseStep(next));
+          model, createCreateResponseStep(next));
     }
 
     ResponseStep<V1CustomResourceDefinition> createCreateResponseStep(Step next) {
@@ -436,7 +447,7 @@ Step updateExistingCrd(Step next, V1CustomResourceDefinition existingCrd) {
                   .served(true));
 
       return new CallBuilder().replaceCustomResourceDefinitionAsync(
-              existingCrd.getMetadata().getName(), existingCrd, createReplaceResponseStep(next));
+          existingCrd.getMetadata().getName(), existingCrd, createReplaceResponseStep(next));
     }
 
     Step updateExistingBetaCrd(Step next, V1beta1CustomResourceDefinition existingCrd) {
@@ -518,6 +529,9 @@ public NextAction onSuccess(
           Packet packet, CallResponse<V1beta1CustomResourceDefinition> callResponse) {
         V1beta1CustomResourceDefinition existingCrd = callResponse.getResult();
         if (version.isCrdV1Supported()) {
+          /* MARKER-2.6.0-ONLY */
+          Main.useDomainStatusEndpoint.set(true);
+          /* END-2.6.0-ONLY */
           if (existingCrd == null) {
             return doNext(createCrd(getNext()), packet);
           } else {
@@ -529,12 +543,26 @@ public NextAction onSuccess(
           } else if (isOutdatedBetaCrd(existingCrd)) {
             return doNext(updateBetaCrd(getNext(), existingCrd), packet);
           } else if (!existingBetaCrdContainsVersion(existingCrd)) {
+            /* MARKER-2.6.0-ONLY */
+            checkForStatusSubresource(existingCrd);
+            /* END-2.6.0-ONLY */
             return doNext(updateExistingBetaCrd(getNext(), existingCrd), packet);
           }
+          /* MARKER-2.6.0-ONLY */
+          checkForStatusSubresource(existingCrd);
+          /* END-2.6.0-ONLY */
         }
         return doNext(packet);
       }
 
+      /* MARKER-2.6.0-ONLY */
+      private void checkForStatusSubresource(V1beta1CustomResourceDefinition existingCrd) {
+        if (existingCrd.getSpec().getSubresources().getStatus() != null) {
+          Main.useDomainStatusEndpoint.set(true);
+        }
+      }
+      /* END-2.6.0-ONLY */
+
       @Override
       protected NextAction onFailureNoRetry(Packet packet, CallResponse<V1beta1CustomResourceDefinition> callResponse) {
         return isNotAuthorizedOrForbidden(callResponse)