Brought back the deprecated _aliases api.

src/main/java/org/elasticsearch/rest/action/RestActionModule.java

@@ -46,6 +46,7 @@ import org.elasticsearch.rest.action.admin.cluster.tasks.RestPendingClusterTasks
 import org.elasticsearch.rest.action.admin.indices.alias.RestIndicesAliasesAction;
 import org.elasticsearch.rest.action.admin.indices.alias.delete.RestIndexDeleteAliasesAction;
 import org.elasticsearch.rest.action.admin.indices.alias.get.RestGetAliasesAction;
+import org.elasticsearch.rest.action.admin.indices.alias.get.RestGetIndicesAliasesAction;
 import org.elasticsearch.rest.action.admin.indices.alias.head.RestAliasesExistAction;
 import org.elasticsearch.rest.action.admin.indices.alias.put.RestIndexPutAliasAction;
 import org.elasticsearch.rest.action.admin.indices.analyze.RestAnalyzeAction;
@@ -151,6 +152,7 @@ public class RestActionModule extends AbstractModule {
         bind(RestIndexDeleteAliasesAction.class).asEagerSingleton();
         bind(RestIndexPutAliasAction.class).asEagerSingleton();
         bind(RestIndicesAliasesAction.class).asEagerSingleton();
+        bind(RestGetIndicesAliasesAction.class).asEagerSingleton();
         bind(RestCreateIndexAction.class).asEagerSingleton();
         bind(RestDeleteIndexAction.class).asEagerSingleton();
         bind(RestCloseIndexAction.class).asEagerSingleton();

src/main/java/org/elasticsearch/rest/action/admin/indices/alias/get/RestGetIndicesAliasesAction.java

@@ -0,0 +1,86 @@
+package org.elasticsearch.rest.action.admin.indices.alias.get;
+
+import com.carrotsearch.hppc.cursors.ObjectCursor;
+import org.elasticsearch.action.ActionListener;
+import org.elasticsearch.action.admin.cluster.state.ClusterStateRequest;
+import org.elasticsearch.action.admin.cluster.state.ClusterStateResponse;
+import org.elasticsearch.client.Client;
+import org.elasticsearch.client.Requests;
+import org.elasticsearch.cluster.metadata.AliasMetaData;
+import org.elasticsearch.cluster.metadata.IndexMetaData;
+import org.elasticsearch.cluster.metadata.MetaData;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.inject.Inject;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.xcontent.ToXContent;
+import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.rest.*;
+import org.elasticsearch.rest.action.support.RestXContentBuilder;
+
+import java.io.IOException;
+
+import static org.elasticsearch.rest.RestRequest.Method.GET;
+import static org.elasticsearch.rest.RestStatus.OK;
+
+/**
+ */
+@Deprecated
+public class RestGetIndicesAliasesAction extends BaseRestHandler {
+
+    @Inject
+    public RestGetIndicesAliasesAction(Settings settings, Client client, RestController controller) {
+        super(settings, client);
+        controller.registerHandler(GET, "/_aliases", this);
+        controller.registerHandler(GET, "/{index}/_aliases", this);
+    }
+
+    @Override
+    public void handleRequest(final RestRequest request, final RestChannel channel) {
+        final String[] indices = Strings.splitStringByCommaToArray(request.param("index"));
+
+        ClusterStateRequest clusterStateRequest = Requests.clusterStateRequest()
+                .filterRoutingTable(true)
+                .filterNodes(true)
+                .filteredIndices(indices);
+
+        clusterStateRequest.listenerThreaded(false);
+
+        client.admin().cluster().state(clusterStateRequest, new ActionListener<ClusterStateResponse>() {
+            @Override
+            public void onResponse(ClusterStateResponse response) {
+                try {
+                    MetaData metaData = response.getState().metaData();
+                    XContentBuilder builder = RestXContentBuilder.restContentBuilder(request);
+                    builder.startObject();
+
+                    for (IndexMetaData indexMetaData : metaData) {
+                        builder.startObject(indexMetaData.index(), XContentBuilder.FieldCaseConversion.NONE);
+
+                        builder.startObject("aliases");
+                        for (ObjectCursor<AliasMetaData> cursor : indexMetaData.aliases().values()) {
+                            AliasMetaData.Builder.toXContent(cursor.value, builder, ToXContent.EMPTY_PARAMS);
+                        }
+                        builder.endObject();
+
+                        builder.endObject();
+                    }
+
+                    builder.endObject();
+
+                    channel.sendResponse(new XContentRestResponse(request, OK, builder));
+                } catch (Throwable e) {
+                    onFailure(e);
+                }
+            }
+
+            @Override
+            public void onFailure(Throwable e) {
+                try {
+                    channel.sendResponse(new XContentThrowableRestResponse(request, e));
+                } catch (IOException e1) {
+                    logger.error("Failed to send failure response", e1);
+                }
+            }
+        });
+    }
+}