Backport owls-80135

Author: rjeberhard

operator/src/main/java/oracle/kubernetes/operator/steps/ManagedServersUpStep.java

@@ -100,21 +100,7 @@ public NextAction apply(Packet packet) {
       LOGGER.fine(SERVERS_UP_MSG, factory.domain.getDomainUid(), getRunningServers(info));
     }
 
-    Set<String> clusteredServers = new HashSet<>();
-
-    for (WlsClusterConfig clusterConfig : config.getClusterConfigs().values()) {
-      factory.logIfInvalidReplicaCount(clusterConfig);
-      for (WlsServerConfig serverConfig : clusterConfig.getServerConfigs()) {
-        factory.addServerIfNeeded(serverConfig, clusterConfig);
-        clusteredServers.add(serverConfig.getName());
-      }
-    }
-
-    for (WlsServerConfig serverConfig : config.getServerConfigs().values()) {
-      if (!clusteredServers.contains(serverConfig.getName())) {
-        factory.addServerIfNeeded(serverConfig, null);
-      }
-    }
+    Optional.ofNullable(config).ifPresent(wlsDomainConfig -> addServersToFactory(factory, wlsDomainConfig));
 
     info.setServerStartupInfo(factory.getStartupInfos());
     LOGGER.exiting();
@@ -125,6 +111,27 @@ public NextAction apply(Packet packet) {
         packet);
   }
 
+  private void addServersToFactory(@Nonnull ServersUpStepFactory factory, @Nonnull WlsDomainConfig wlsDomainConfig) {
+    Set<String> clusteredServers = new HashSet<>();
+
+    wlsDomainConfig.getClusterConfigs().values()
+        .forEach(wlsClusterConfig -> addClusteredServersToFactory(factory, clusteredServers, wlsClusterConfig));
+
+    wlsDomainConfig.getServerConfigs().values().stream()
+        .filter(wlsServerConfig -> !clusteredServers.contains(wlsServerConfig.getName()))
+        .forEach(wlsServerConfig -> factory.addServerIfNeeded(wlsServerConfig, null));
+  }
+
+  private void addClusteredServersToFactory(@Nonnull ServersUpStepFactory factory, Set<String> clusteredServers,
+                                            @Nonnull WlsClusterConfig wlsClusterConfig) {
+    factory.logIfInvalidReplicaCount(wlsClusterConfig);
+    wlsClusterConfig.getServerConfigs()
+        .forEach(wlsServerConfig -> {
+          factory.addServerIfNeeded(wlsServerConfig, wlsClusterConfig);
+          clusteredServers.add(wlsServerConfig.getName());
+        });
+  }
+
   // an interface to provide a hook for unit testing.
   interface NextStepFactory {
     Step createServerStep(
@@ -158,7 +165,7 @@ boolean shouldPrecreateServerService(ServerSpec server) {
       return false;
     }
 
-    void addServerIfNeeded(@Nonnull WlsServerConfig serverConfig, WlsClusterConfig clusterConfig) {
+    private void addServerIfNeeded(@Nonnull WlsServerConfig serverConfig, WlsClusterConfig clusterConfig) {
       String serverName = serverConfig.getName();
       if (servers.contains(serverName) || serverName.equals(domainTopology.getAdminServerName())) {
         return;

operator/src/test/java/oracle/kubernetes/operator/steps/ManagedServersUpStepTest.java

@@ -562,6 +562,13 @@ public void whenReplicasLessThanMinDynClusterSize_allowBelowMin_doNotChangeRepli
     assertThat(0, equalTo(domain.getReplicaCount("cluster1")));
   }
 
+  @Test
+  public void whenDomainToplogyIsMissing_noExceptionAndDontStartServers() {
+    invokeStepWithoutDomainTopology();
+
+    assertServersWillNotBeStarted();
+  }
+
   private void assertStoppingServers(Step step, String... servers) {
     assertThat(((ServerDownIteratorStep) step).getServersToStop(), containsInAnyOrder(servers));
   }
@@ -655,6 +662,12 @@ private void invokeStep() {
     testSupport.runSteps(step);
   }
 
+  private void invokeStepWithoutDomainTopology() {
+    configSupport.setAdminServerName(ADMIN);
+
+    testSupport.runSteps(step);
+  }
+
   static class TestStepFactory implements ManagedServersUpStep.NextStepFactory {
     private static DomainPresenceInfo info;