Remove usage of index.shrink.source.* in 7.x (#33271)

We cut over to `index.resize.source.*` but still have these constants
being public in `IndexMetaData`. Those Settings and constants are not needed
in 7.x while we still need to keep the keys known to private settings since
they might be part of the index settings of old indices. We can remove that
in 8.0. Yet, we should remove the settings to make sure they are not used again.

Author: s1monw

server/src/main/java/org/elasticsearch/cluster/metadata/IndexMetaData.java

@@ -485,22 +485,14 @@ public MappingMetaData mapping(String mappingType) {
         return mappings.get(mappingType);
     }
 
-    // we keep the shrink settings for BWC - this can be removed in 8.0
-    // we can't remove in 7 since this setting might be baked into an index coming in via a full cluster restart from 6.0
-    public static final String INDEX_SHRINK_SOURCE_UUID_KEY = "index.shrink.source.uuid";
-    public static final String INDEX_SHRINK_SOURCE_NAME_KEY = "index.shrink.source.name";
     public static final String INDEX_RESIZE_SOURCE_UUID_KEY = "index.resize.source.uuid";
     public static final String INDEX_RESIZE_SOURCE_NAME_KEY = "index.resize.source.name";
-    public static final Setting<String> INDEX_SHRINK_SOURCE_UUID = Setting.simpleString(INDEX_SHRINK_SOURCE_UUID_KEY);
-    public static final Setting<String> INDEX_SHRINK_SOURCE_NAME = Setting.simpleString(INDEX_SHRINK_SOURCE_NAME_KEY);
-    public static final Setting<String> INDEX_RESIZE_SOURCE_UUID = Setting.simpleString(INDEX_RESIZE_SOURCE_UUID_KEY,
-        INDEX_SHRINK_SOURCE_UUID);
-    public static final Setting<String> INDEX_RESIZE_SOURCE_NAME = Setting.simpleString(INDEX_RESIZE_SOURCE_NAME_KEY,
-        INDEX_SHRINK_SOURCE_NAME);
+    public static final Setting<String> INDEX_RESIZE_SOURCE_UUID = Setting.simpleString(INDEX_RESIZE_SOURCE_UUID_KEY);
+    public static final Setting<String> INDEX_RESIZE_SOURCE_NAME = Setting.simpleString(INDEX_RESIZE_SOURCE_NAME_KEY);
 
     public Index getResizeSourceIndex() {
-        return INDEX_RESIZE_SOURCE_UUID.exists(settings) || INDEX_SHRINK_SOURCE_UUID.exists(settings)
-            ? new Index(INDEX_RESIZE_SOURCE_NAME.get(settings), INDEX_RESIZE_SOURCE_UUID.get(settings)) : null;
+        return INDEX_RESIZE_SOURCE_UUID.exists(settings) ? new Index(INDEX_RESIZE_SOURCE_NAME.get(settings),
+            INDEX_RESIZE_SOURCE_UUID.get(settings)) : null;
     }
 
     /**

server/src/main/java/org/elasticsearch/cluster/metadata/MetaDataCreateIndexService.java

@@ -723,10 +723,7 @@ static void prepareResizeIndexSettings(
                 .put(IndexMetaData.INDEX_ROUTING_INITIAL_RECOVERY_GROUP_SETTING.getKey() + "_id",
                     Strings.arrayToCommaDelimitedString(nodesToAllocateOn.toArray()))
                 // we only try once and then give up with a shrink index
-                .put("index.allocation.max_retries", 1)
-                // we add the legacy way of specifying it here for BWC. We can remove this once it's backported to 6.x
-                .put(IndexMetaData.INDEX_SHRINK_SOURCE_NAME.getKey(), resizeSourceIndex.getName())
-                .put(IndexMetaData.INDEX_SHRINK_SOURCE_UUID.getKey(), resizeSourceIndex.getUUID());
+                .put("index.allocation.max_retries", 1);
         } else if (type == ResizeType.SPLIT) {
             validateSplitIndex(currentState, resizeSourceIndex.getName(), mappingKeys, resizeIntoName, indexSettingsBuilder.build());
         } else {

server/src/main/java/org/elasticsearch/common/settings/IndexScopedSettings.java

@@ -202,8 +202,10 @@ public boolean isPrivateSetting(String key) {
             case IndexMetaData.SETTING_VERSION_UPGRADED:
             case IndexMetaData.SETTING_INDEX_PROVIDED_NAME:
             case MergePolicyConfig.INDEX_MERGE_ENABLED:
-            case IndexMetaData.INDEX_SHRINK_SOURCE_UUID_KEY:
-            case IndexMetaData.INDEX_SHRINK_SOURCE_NAME_KEY:
+                // we keep the shrink settings for BWC - this can be removed in 8.0
+                // we can't remove in 7 since this setting might be baked into an index coming in via a full cluster restart from 6.0
+            case "index.shrink.source.uuid":
+            case "index.shrink.source.name":
             case IndexMetaData.INDEX_RESIZE_SOURCE_UUID_KEY:
             case IndexMetaData.INDEX_RESIZE_SOURCE_NAME_KEY:
                 return true;

server/src/test/java/org/elasticsearch/cluster/routing/allocation/decider/DiskThresholdDeciderUnitTests.java

@@ -286,16 +286,19 @@ public void testSizeShrinkIndex() {
         metaBuilder.put(IndexMetaData.builder("test").settings(settings(Version.CURRENT).put("index.uuid", "1234"))
             .numberOfShards(4).numberOfReplicas(0));
         metaBuilder.put(IndexMetaData.builder("target").settings(settings(Version.CURRENT).put("index.uuid", "5678")
-            .put("index.shrink.source.name", "test").put("index.shrink.source.uuid", "1234")).numberOfShards(1).numberOfReplicas(0));
+            .put(IndexMetaData.INDEX_RESIZE_SOURCE_NAME_KEY, "test").put(IndexMetaData.INDEX_RESIZE_SOURCE_UUID_KEY, "1234"))
+            .numberOfShards(1)
+            .numberOfReplicas(0));
         metaBuilder.put(IndexMetaData.builder("target2").settings(settings(Version.CURRENT).put("index.uuid", "9101112")
-            .put("index.shrink.source.name", "test").put("index.shrink.source.uuid", "1234")).numberOfShards(2).numberOfReplicas(0));
+            .put(IndexMetaData.INDEX_RESIZE_SOURCE_NAME_KEY, "test").put(IndexMetaData.INDEX_RESIZE_SOURCE_UUID_KEY, "1234"))
+            .numberOfShards(2).numberOfReplicas(0));
         MetaData metaData = metaBuilder.build();
         RoutingTable.Builder routingTableBuilder = RoutingTable.builder();
         routingTableBuilder.addAsNew(metaData.index("test"));
         routingTableBuilder.addAsNew(metaData.index("target"));
         routingTableBuilder.addAsNew(metaData.index("target2"));
-        ClusterState clusterState = ClusterState.builder(org.elasticsearch.cluster.ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY))
-            .metaData(metaData).routingTable(routingTableBuilder.build()).build();
+        ClusterState clusterState = ClusterState.builder(org.elasticsearch.cluster.ClusterName.CLUSTER_NAME_SETTING
+            .getDefault(Settings.EMPTY)).metaData(metaData).routingTable(routingTableBuilder.build()).build();
 
         AllocationService allocationService = createAllocationService();
         clusterState = ClusterState.builder(clusterState).nodes(DiscoveryNodes.builder().add(newNode("node1")))
@@ -330,7 +333,6 @@ public void testSizeShrinkIndex() {
         assertEquals(100L, DiskThresholdDecider.getExpectedShardSize(test_1, allocation, 0));
         assertEquals(10L, DiskThresholdDecider.getExpectedShardSize(test_0, allocation, 0));
 
-
         ShardRouting target = ShardRouting.newUnassigned(new ShardId(new Index("target", "5678"), 0),
             true, LocalShardsRecoverySource.INSTANCE, new UnassignedInfo(UnassignedInfo.Reason.INDEX_CREATED, "foo"));
         assertEquals(1110L, DiskThresholdDecider.getExpectedShardSize(target, allocation, 0));
@@ -350,12 +352,9 @@ public void testSizeShrinkIndex() {
             .build();
 
         allocationService.reroute(clusterState, "foo");
-
         RoutingAllocation allocationWithMissingSourceIndex = new RoutingAllocation(null,
             clusterStateWithMissingSourceIndex.getRoutingNodes(), clusterStateWithMissingSourceIndex, info, 0);
-
         assertEquals(42L, DiskThresholdDecider.getExpectedShardSize(target, allocationWithMissingSourceIndex, 42L));
         assertEquals(42L, DiskThresholdDecider.getExpectedShardSize(target2, allocationWithMissingSourceIndex, 42L));
     }
-
 }

server/src/test/java/org/elasticsearch/cluster/routing/allocation/decider/FilterAllocationDeciderTests.java

@@ -42,8 +42,8 @@
 import java.util.Arrays;
 import java.util.Collections;
 
-import static org.elasticsearch.cluster.metadata.IndexMetaData.INDEX_SHRINK_SOURCE_NAME;
-import static org.elasticsearch.cluster.metadata.IndexMetaData.INDEX_SHRINK_SOURCE_UUID;
+import static org.elasticsearch.cluster.metadata.IndexMetaData.INDEX_RESIZE_SOURCE_NAME;
+import static org.elasticsearch.cluster.metadata.IndexMetaData.INDEX_RESIZE_SOURCE_UUID;
 import static org.elasticsearch.cluster.routing.ShardRoutingState.INITIALIZING;
 import static org.elasticsearch.cluster.routing.ShardRoutingState.STARTED;
 import static org.elasticsearch.cluster.routing.ShardRoutingState.UNASSIGNED;
@@ -151,8 +151,8 @@ private ClusterState createInitialClusterState(AllocationService service, Settin
                 .putInSyncAllocationIds(1, Collections.singleton("aid1"))
                 .build();
             metaData.put(sourceIndex, false);
-            indexSettings.put(INDEX_SHRINK_SOURCE_UUID.getKey(), sourceIndex.getIndexUUID());
-            indexSettings.put(INDEX_SHRINK_SOURCE_NAME.getKey(), sourceIndex.getIndex().getName());
+            indexSettings.put(INDEX_RESIZE_SOURCE_UUID.getKey(), sourceIndex.getIndexUUID());
+            indexSettings.put(INDEX_RESIZE_SOURCE_NAME.getKey(), sourceIndex.getIndex().getName());
         } else {
             sourceIndex = null;
         }