ISPN-12667 GlobalState incompatibility between 11.x and 12.x

core/src/main/java/org/infinispan/distribution/ch/impl/ReplicatedConsistentHash.java

@@ -125,7 +125,11 @@ public ReplicatedConsistentHash union(ReplicatedConsistentHash ch2) {
 
    private static List<Address> parseMembers(ScopedPersistentState state, String numMembersPropertyName,
                                              String memberPropertyFormat) {
-      int numMembers = Integer.parseInt(state.getProperty(numMembersPropertyName));
+      String property = state.getProperty(numMembersPropertyName);
+      if (property == null) {
+          return Collections.emptyList();
+      }
+      int numMembers = Integer.parseInt(property);
       List<Address> members = new ArrayList<>(numMembers);
       for (int i = 0; i < numMembers; i++) {
          PersistentUUID uuid = PersistentUUID.fromString(state.getProperty(String.format(memberPropertyFormat, i)));

core/src/test/java/org/infinispan/globalstate/GlobalStateBackwardsCompatibilityTest.java

@@ -0,0 +1,88 @@
+package org.infinispan.globalstate;
+
+import static org.infinispan.commons.test.CommonsTestingUtil.tmpDirectory;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.util.Properties;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+import org.infinispan.commons.util.Util;
+import org.infinispan.configuration.cache.CacheMode;
+import org.infinispan.configuration.cache.ConfigurationBuilder;
+import org.infinispan.configuration.global.GlobalConfigurationBuilder;
+import org.infinispan.manager.EmbeddedCacheManager;
+import org.infinispan.test.MultipleCacheManagersTest;
+import org.infinispan.topology.PersistentUUID;
+import org.testng.annotations.AfterClass;
+import org.testng.annotations.Test;
+
+/**
+ * ISPN-12667 A test to ensure that global state properties from previous Infinispan majors are compatible.
+ *
+ * @author Ryan Emerson
+ * @since 12.0
+ */
+@Test(groups = "functional", testName = "globalstate.GlobalStateBackwardsCompatibilityTest")
+public class GlobalStateBackwardsCompatibilityTest extends MultipleCacheManagersTest {
+   private static final String CACHE_NAME = "testCache";
+   private static final String MEMBER_0 = PersistentUUID.randomUUID().toString();
+   private static final String MEMBER_1 = PersistentUUID.randomUUID().toString();
+
+   @Override
+   protected void createCacheManagers() throws Throwable {
+      createCacheManagerWithGlobalState(MEMBER_0, tmpDirectory(this.getClass().getSimpleName(), "0"));
+      createCacheManagerWithGlobalState(MEMBER_1, tmpDirectory(this.getClass().getSimpleName(), "1"));
+      waitForClusterToForm(CACHE_NAME);
+   }
+
+   @AfterClass(alwaysRun = true)
+   @Override
+   protected void destroy() {
+      super.destroy();
+      Util.recursiveFileRemove(tmpDirectory(this.getClass().getSimpleName()));
+   }
+
+   private void createCacheManagerWithGlobalState(String uuid, String stateDirectory) throws Exception {
+      new File(stateDirectory).mkdirs();
+      createCacheState(stateDirectory);
+
+      Properties globalState = new Properties();
+      globalState.put("@version", "11.0.9.Final");
+      globalState.put("version-major", "11");
+      globalState.put("@timestamp", "2021-01-28T10\\:53\\:56.289272Z");
+      globalState.put("uuid", uuid);
+      globalState.store(new FileOutputStream(new File(stateDirectory, "___global.state")), null);
+
+      GlobalConfigurationBuilder global = GlobalConfigurationBuilder.defaultClusteredBuilder();
+      global.globalState().enable().persistentLocation(stateDirectory);
+
+      ConfigurationBuilder config = new ConfigurationBuilder();
+      config.clustering().cacheMode(CacheMode.REPL_SYNC).stateTransfer().timeout(1, TimeUnit.SECONDS)
+            .persistence().addSingleFileStore().location(stateDirectory);
+      EmbeddedCacheManager manager = addClusterEnabledCacheManager(global, null);
+      manager.defineConfiguration(CACHE_NAME, config.build());
+   }
+
+   private void createCacheState(String stateDirectory) throws Exception {
+      Properties cacheState = new Properties();
+      cacheState.put("@version", "11.0.9.Final");
+      cacheState.put("@timestamp", "2021-01-28T10\\:53\\:56.289272Z");
+      cacheState.put("version-major", "11");
+      cacheState.put("consistentHash", "org.infinispan.distribution.ch.impl.ReplicatedConsistentHash");
+      cacheState.put("members", "2");
+      cacheState.put("member.0", MEMBER_0);
+      cacheState.put("member.1", MEMBER_1);
+      cacheState.put("capacityFactors", "2");
+      cacheState.put("capacityFactor.0", "1.0");
+      cacheState.put("capacityFactor.1", "1.0");
+      cacheState.put("primaryOwners", "256");
+      IntStream.range(0, 256).forEach(i -> cacheState.put("primaryOwners." + i, Integer.toString(i % 2)));
+      cacheState.store(new FileOutputStream(new File(stateDirectory, CACHE_NAME + ".state")), null);
+   }
+
+   @Test
+   public void compatibilityTest() {
+   }
+}