Expose system index metadata in CAT indices

rest-api-spec/src/main/resources/rest-api-spec/api/cat.indices.json

@@ -78,6 +78,10 @@
         ],
         "description":"A health status (\"green\", \"yellow\", or \"red\" to filter only indices matching the specified health status"
       },
+      "system":{
+        "type":"boolean",
+        "description":"If specified, return only system indices when true or only non-system indices when false"
+      },
       "help":{
         "type":"boolean",
         "description":"Return help information",

server/src/main/java/org/opensearch/action/ActionModule.java

@@ -582,6 +582,7 @@ public class ActionModule extends AbstractModule {
     private final RequestValidators<IndicesAliasesRequest> indicesAliasesRequestRequestValidators;
     private final ThreadPool threadPool;
     private final ExtensionsManager extensionsManager;
+    private final SystemIndices systemIndices;
     private final ResponseLimitSettings responseLimitSettings;
 
     public ActionModule(
@@ -607,6 +608,7 @@ public ActionModule(
         this.actionPlugins = actionPlugins;
         this.threadPool = threadPool;
         this.extensionsManager = extensionsManager;
+        this.systemIndices = systemIndices;
         actions = setupActions(actionPlugins);
         actionFilters = setupActionFilters(actionPlugins);
         dynamicActionRegistry = new DynamicActionRegistry();
@@ -1059,7 +1061,7 @@ public void initRestHandlers(Supplier<DiscoveryNodes> nodesInCluster) {
         registerHandler.accept(new RestClusterManagerAction());
         registerHandler.accept(new RestNodesAction());
         registerHandler.accept(new RestTasksAction(nodesInCluster));
-        registerHandler.accept(new RestIndicesAction(responseLimitSettings));
+        registerHandler.accept(new RestIndicesAction(responseLimitSettings, systemIndices));
         registerHandler.accept(new RestSegmentsAction(responseLimitSettings));
         // Fully qualified to prevent interference with rest.action.count.RestCountAction
         registerHandler.accept(new org.opensearch.rest.action.cat.RestCountAction());
@@ -1077,7 +1079,7 @@ public void initRestHandlers(Supplier<DiscoveryNodes> nodesInCluster) {
         registerHandler.accept(new RestTemplatesAction());
 
         // LIST API
-        registerHandler.accept(new RestIndicesListAction(responseLimitSettings));
+        registerHandler.accept(new RestIndicesListAction(responseLimitSettings, systemIndices));
         registerHandler.accept(new RestShardsListAction());
 
         // Point in time API

server/src/main/java/org/opensearch/rest/action/cat/RestIndicesAction.java

@@ -63,6 +63,8 @@
 import org.opensearch.core.common.Strings;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.merge.MergedSegmentWarmerStats;
+import org.opensearch.indices.SystemIndexDescriptor;
+import org.opensearch.indices.SystemIndices;
 import org.opensearch.rest.RestRequest;
 import org.opensearch.rest.RestResponse;
 import org.opensearch.rest.action.RestResponseListener;
@@ -106,10 +108,12 @@ public class RestIndicesAction extends AbstractListAction {
     private static final String DUPLICATE_PARAMETER_ERROR_MESSAGE =
         "Please only use one of the request parameters [master_timeout, cluster_manager_timeout].";
 
+    private final SystemIndices systemIndices;
     private final ResponseLimitSettings responseLimitSettings;
 
-    public RestIndicesAction(ResponseLimitSettings responseLimitSettings) {
+    public RestIndicesAction(ResponseLimitSettings responseLimitSettings, SystemIndices systemIndices) {
         this.responseLimitSettings = responseLimitSettings;
+        this.systemIndices = systemIndices;
     }
 
     @Override
@@ -397,7 +401,7 @@ public void onFailure(final Exception e) {
     private static final Set<String> RESPONSE_PARAMS;
 
     static {
-        final Set<String> responseParams = new HashSet<>(asList("local", "health"));
+        final Set<String> responseParams = new HashSet<>(asList("local", "health", "system"));
         responseParams.addAll(AbstractCatAction.RESPONSE_PARAMS);
         RESPONSE_PARAMS = Collections.unmodifiableSet(responseParams);
     }
@@ -430,6 +434,13 @@ protected Table getTableWithHeader(final RestRequest request, final PageToken pa
         table.addCell("store.size", "sibling:pri;alias:ss,storeSize;text-align:right;desc:store size of primaries & replicas");
         table.addCell("pri.store.size", "text-align:right;desc:store size of primaries");
 
+        final String systemColumnDefault = request.hasParam("system") ? "" : "default:false;";
+        table.addCell("system", "alias:sys;" + systemColumnDefault + "desc:whether the index is a system index");
+        table.addCell(
+            "system.description",
+            "alias:sysdesc;" + systemColumnDefault + "desc:description from the matching system index descriptor"
+        );
+
         table.addCell("completion.size", "sibling:pri;alias:cs,completionSize;default:false;text-align:right;desc:size of completion");
         table.addCell("pri.completion.size", "default:false;text-align:right;desc:size of completion");
 
@@ -899,6 +910,7 @@ protected Table buildTable(
         final PageToken pageToken
     ) {
         final String healthParam = request.param("health");
+        final Boolean systemParam = request.hasParam("system") ? request.paramAsBoolean("system", false) : null;
         final Table table = getTableWithHeader(request, pageToken);
 
         while (tableIterator.hasNext()) {
@@ -942,6 +954,10 @@ protected Table buildTable(
                 }
             }
 
+            if (systemParam != null && systemParam != indexMetadata.isSystem()) {
+                continue;
+            }
+
             final CommonStats primaryStats;
             final CommonStats totalStats;
 
@@ -971,6 +987,10 @@ protected Table buildTable(
             table.addCell(totalStats.getStore() == null ? null : totalStats.getStore().size());
             table.addCell(primaryStats.getStore() == null ? null : primaryStats.getStore().size());
 
+            table.addCell(indexMetadata.isSystem());
+            SystemIndexDescriptor descriptor = indexMetadata.isSystem() ? systemIndices.findMatchingDescriptor(indexName) : null;
+            table.addCell(descriptor == null ? null : descriptor.getDescription());
+
             table.addCell(totalStats.getCompletion() == null ? null : totalStats.getCompletion().getSize());
             table.addCell(primaryStats.getCompletion() == null ? null : primaryStats.getCompletion().getSize());
 

server/src/main/java/org/opensearch/rest/action/list/RestIndicesListAction.java

@@ -14,6 +14,7 @@
 import org.opensearch.common.breaker.ResponseLimitSettings;
 import org.opensearch.common.collect.Tuple;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.indices.SystemIndices;
 import org.opensearch.rest.RestRequest;
 import org.opensearch.rest.action.cat.RestIndicesAction;
 
@@ -36,8 +37,8 @@ public class RestIndicesListAction extends RestIndicesAction {
     private static final int MAX_SUPPORTED_LIST_INDICES_PAGE_SIZE = 5000;
     private static final int DEFAULT_LIST_INDICES_PAGE_SIZE = 500;
 
-    public RestIndicesListAction(final ResponseLimitSettings responseLimitSettings) {
-        super(responseLimitSettings);
+    public RestIndicesListAction(final ResponseLimitSettings responseLimitSettings, final SystemIndices systemIndices) {
+        super(responseLimitSettings, systemIndices);
     }
 
     @Override

server/src/test/java/org/opensearch/action/RenamedTimeoutRequestParameterTests.java

@@ -18,6 +18,7 @@
 import org.opensearch.core.common.bytes.BytesArray;
 import org.opensearch.core.xcontent.MediaTypeRegistry;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
+import org.opensearch.indices.SystemIndices;
 import org.opensearch.rest.BaseRestHandler;
 import org.opensearch.rest.action.admin.cluster.RestCleanupRepositoryAction;
 import org.opensearch.rest.action.admin.cluster.RestCloneSnapshotAction;
@@ -159,7 +160,7 @@ public void testCatIndices() {
         ClusterSettings clusterSettings = new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
         Settings settings = Settings.builder().build();
         ResponseLimitSettings responseLimitSettings = new ResponseLimitSettings(clusterSettings, settings);
-        RestIndicesAction action = new RestIndicesAction(responseLimitSettings);
+        RestIndicesAction action = new RestIndicesAction(responseLimitSettings, new SystemIndices(Collections.emptyMap()));
         Exception e = assertThrows(OpenSearchParseException.class, () -> action.doCatRequest(getRestRequestWithBothParams(), client));
         assertThat(e.getMessage(), containsString(DUPLICATE_PARAMETER_ERROR_MESSAGE));
         assertWarnings(MASTER_TIMEOUT_DEPRECATED_MESSAGE);