iter

server/src/main/java/org/elasticsearch/action/AliasesRequest.java

@@ -33,9 +33,9 @@ public interface AliasesRequest extends IndicesRequest.Replaceable {
     String[] aliases();
 
     /**
-     * Replaces the aliases that the action relates to
+     * Replaces current aliases with the provided aliases.
      *
-     * This is an internal method.
+     * Sometimes aliases expressions need to be resolved to concrete aliases prior to executing the transport action.
      */
     void replaceAliases(String... aliases);
 

server/src/main/java/org/elasticsearch/action/admin/indices/alias/get/GetAliasesRequest.java

@@ -98,9 +98,9 @@ public void replaceAliases(String... aliases) {
     }
 
     /**
-     * Returns aliases originally specified by the user
+     * Returns the aliases as was originally specified by the user
      */
-    String[] getOriginalAliases() {
+    public String[] getOriginalAliases() {
         return originalAliases;
     }
 

server/src/main/java/org/elasticsearch/action/admin/indices/alias/get/TransportGetAliasesAction.java

@@ -27,7 +27,6 @@
 import org.elasticsearch.cluster.metadata.AliasMetaData;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.cluster.service.ClusterService;
-import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.collect.ImmutableOpenMap;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
@@ -64,17 +63,24 @@ protected GetAliasesResponse newResponse() {
     @Override
     protected void masterOperation(GetAliasesRequest request, ClusterState state, ActionListener<GetAliasesResponse> listener) {
         String[] concreteIndices = indexNameExpressionResolver.concreteIndexNames(state, request);
-        ImmutableOpenMap<String, List<AliasMetaData>> result = state.metaData().findAliases(request.aliases(), concreteIndices);
+        ImmutableOpenMap<String, List<AliasMetaData>> aliases = state.metaData().findAliases(request.aliases(), concreteIndices);
+        listener.onResponse(new GetAliasesResponse(postProcess(request, concreteIndices, aliases)));
+    }
 
-        // in case all aliases are requested then it is desired to return the concrete index with no aliases (#25114):
-        boolean aliasesProvided = Strings.isAllOrWildcard(request.getOriginalAliases());
-        ImmutableOpenMap.Builder<String, List<AliasMetaData>> mapBuilder = ImmutableOpenMap.builder(result);
+    /**
+     * Fills alias result with empty entries for requested indices when no specific aliases were requested.
+     */
+    static ImmutableOpenMap<String, List<AliasMetaData>> postProcess(GetAliasesRequest request, String[] concreteIndices,
+                                                                     ImmutableOpenMap<String, List<AliasMetaData>> aliases) {
+        boolean noAliasesSpecified = request.getOriginalAliases() == null || request.getOriginalAliases().length == 0;
+        ImmutableOpenMap.Builder<String, List<AliasMetaData>> mapBuilder = ImmutableOpenMap.builder(aliases);
         for (String index : concreteIndices) {
-            if (result.get(index) == null && aliasesProvided) {
-                mapBuilder.put(index, Collections.emptyList());
+            if (aliases.get(index) == null && noAliasesSpecified) {
+                List<AliasMetaData> previous = mapBuilder.put(index, Collections.emptyList());
+                assert previous == null;
             }
         }
-
-        listener.onResponse(new GetAliasesResponse(mapBuilder.build()));
+        return mapBuilder.build();
     }
+
 }

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

@@ -263,7 +263,7 @@ public ImmutableOpenMap<String, List<AliasMetaData>> findAliases(final String[]
             return ImmutableOpenMap.of();
         }
 
-        boolean matchAllAliases = Strings.isAllOrWildcard(aliases);
+        boolean matchAllAliases = matchAllAliases(aliases);
         ImmutableOpenMap.Builder<String, List<AliasMetaData>> mapBuilder = ImmutableOpenMap.builder();
         for (String index : concreteIndices) {
             IndexMetaData indexMetaData = indices.get(index);
@@ -284,6 +284,15 @@ public ImmutableOpenMap<String, List<AliasMetaData>> findAliases(final String[]
         return mapBuilder.build();
     }
 
+    private static boolean matchAllAliases(final String[] aliases) {
+        for (String alias : aliases) {
+            if (alias.equals(ALL)) {
+                return true;
+            }
+        }
+        return aliases.length == 0;
+    }
+
     /**
      * Checks if at least one of the specified aliases exists in the specified concrete indices. Wildcards are supported in the
      * alias names for partial matches.

server/src/main/java/org/elasticsearch/rest/action/admin/indices/RestGetAliasesAction.java

@@ -77,6 +77,10 @@ public String getName() {
 
     @Override
     public RestChannelConsumer prepareRequest(final RestRequest request, final NodeClient client) throws IOException {
+        // The TransportGetAliasesAction was improved do the same post processing as is happening here.
+        // We can't remove this logic yet to support mixed clusters. We should be able to remove this logic here
+        // in when 8.0 becomes the new version in the master branch.
+
         final boolean namesProvided = request.hasParam("name");
         final String[] aliases = request.paramAsStringArrayOrEmptyIfAll("name");
         final GetAliasesRequest getAliasesRequest = new GetAliasesRequest(aliases);

server/src/test/java/org/elasticsearch/action/admin/indices/alias/get/TransportGetAliasesActionTests.java

@@ -0,0 +1,64 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.elasticsearch.action.admin.indices.alias.get;
+
+import org.elasticsearch.cluster.metadata.AliasMetaData;
+import org.elasticsearch.common.collect.ImmutableOpenMap;
+import org.elasticsearch.test.ESTestCase;
+
+import java.util.Collections;
+import java.util.List;
+
+import static org.hamcrest.Matchers.equalTo;
+
+public class TransportGetAliasesActionTests extends ESTestCase {
+
+    public void testPostProcess() {
+        GetAliasesRequest request = new GetAliasesRequest();
+        ImmutableOpenMap<String, List<AliasMetaData>> aliases = ImmutableOpenMap.<String, List<AliasMetaData>>builder()
+            .fPut("b", Collections.singletonList(new AliasMetaData.Builder("y").build()))
+            .build();
+        ImmutableOpenMap<String, List<AliasMetaData>> result =
+            TransportGetAliasesAction.postProcess(request, new String[]{"a", "b", "c"}, aliases);
+        assertThat(result.size(), equalTo(3));
+        assertThat(result.get("a").size(), equalTo(0));
+        assertThat(result.get("b").size(), equalTo(1));
+        assertThat(result.get("c").size(), equalTo(0));
+
+        request = new GetAliasesRequest();
+        request.replaceAliases("y", "z");
+        aliases = ImmutableOpenMap.<String, List<AliasMetaData>>builder()
+            .fPut("b", Collections.singletonList(new AliasMetaData.Builder("y").build()))
+            .build();
+        result = TransportGetAliasesAction.postProcess(request, new String[]{"a", "b", "c"}, aliases);
+        assertThat(result.size(), equalTo(3));
+        assertThat(result.get("a").size(), equalTo(0));
+        assertThat(result.get("b").size(), equalTo(1));
+        assertThat(result.get("c").size(), equalTo(0));
+
+        request = new GetAliasesRequest("y", "z");
+        aliases = ImmutableOpenMap.<String, List<AliasMetaData>>builder()
+            .fPut("b", Collections.singletonList(new AliasMetaData.Builder("y").build()))
+            .build();
+        result = TransportGetAliasesAction.postProcess(request, new String[]{"a", "b", "c"}, aliases);
+        assertThat(result.size(), equalTo(1));
+        assertThat(result.get("b").size(), equalTo(1));
+    }
+
+}