Do not return all indices if a specific alias is requested via get aliases api.

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

@@ -33,9 +33,11 @@ public interface AliasesRequest extends IndicesRequest.Replaceable {
     String[] aliases();
 
     /**
-     * Sets the array of aliases that the action relates to
+     * Replaces current aliases with the provided aliases.
+     *
+     * Sometimes aliases expressions need to be resolved to concrete aliases prior to executing the transport action.
      */
-    AliasesRequest aliases(String... aliases);
+    void replaceAliases(String... aliases);
 
     /**
      * Returns true if wildcards expressions among aliases should be resolved, false otherwise

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

@@ -302,7 +302,6 @@ public AliasActions index(String index) {
         /**
          * Aliases to use with this action.
          */
-        @Override
         public AliasActions aliases(String... aliases) {
             if (type == AliasActions.Type.REMOVE_INDEX) {
                 throw new IllegalArgumentException("[aliases] is unsupported for [" + type + "]");
@@ -428,6 +427,11 @@ public String[] aliases() {
             return aliases;
         }
 
+        @Override
+        public void replaceAliases(String... aliases) {
+            this.aliases = aliases;
+        }
+
         @Override
         public boolean expandAliasesWildcards() {
             //remove operations support wildcards among aliases, add operations don't

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

@@ -18,6 +18,7 @@
  */
 package org.elasticsearch.action.admin.indices.alias.get;
 
+import org.elasticsearch.Version;
 import org.elasticsearch.action.ActionRequestValidationException;
 import org.elasticsearch.action.AliasesRequest;
 import org.elasticsearch.action.support.IndicesOptions;
@@ -32,15 +33,12 @@ public class GetAliasesRequest extends MasterNodeReadRequest<GetAliasesRequest>
 
     private String[] indices = Strings.EMPTY_ARRAY;
     private String[] aliases = Strings.EMPTY_ARRAY;
-
     private IndicesOptions indicesOptions = IndicesOptions.strictExpand();
+    private String[] originalAliases = Strings.EMPTY_ARRAY;
 
-    public GetAliasesRequest(String[] aliases) {
+    public GetAliasesRequest(String... aliases) {
         this.aliases = aliases;
-    }
-
-    public GetAliasesRequest(String alias) {
-        this.aliases = new String[]{alias};
+        this.originalAliases = aliases;
     }
 
     public GetAliasesRequest() {
@@ -51,6 +49,9 @@ public GetAliasesRequest(StreamInput in) throws IOException {
         indices = in.readStringArray();
         aliases = in.readStringArray();
         indicesOptions = IndicesOptions.readIndicesOptions(in);
+        if (in.getVersion().onOrAfter(Version.V_7_0_0_alpha1)) {
+            originalAliases = in.readStringArray();
+        }
     }
 
     @Override
@@ -59,6 +60,9 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeStringArray(indices);
         out.writeStringArray(aliases);
         indicesOptions.writeIndicesOptions(out);
+        if (out.getVersion().onOrAfter(Version.V_7_0_0_alpha1)) {
+            out.writeStringArray(originalAliases);
+        }
     }
 
     @Override
@@ -67,9 +71,9 @@ public GetAliasesRequest indices(String... indices) {
         return this;
     }
 
-    @Override
     public GetAliasesRequest aliases(String... aliases) {
         this.aliases = aliases;
+        this.originalAliases = aliases;
         return this;
     }
 
@@ -88,6 +92,18 @@ public String[] aliases() {
         return aliases;
     }
 
+    @Override
+    public void replaceAliases(String... aliases) {
+        this.aliases = aliases;
+    }
+
+    /**
+     * Returns the aliases as was originally specified by the user
+     */
+    public String[] getOriginalAliases() {
+        return originalAliases;
+    }
+
     @Override
     public boolean expandAliasesWildcards() {
         return true;

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

@@ -33,6 +33,7 @@
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportService;
 
+import java.util.Collections;
 import java.util.List;
 
 public class TransportGetAliasesAction extends TransportMasterNodeReadAction<GetAliasesRequest, GetAliasesResponse> {
@@ -62,7 +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);
-        listener.onResponse(new GetAliasesResponse(result));
+        ImmutableOpenMap<String, List<AliasMetaData>> aliases = state.metaData().findAliases(request.aliases(), concreteIndices);
+        listener.onResponse(new GetAliasesResponse(postProcess(request, concreteIndices, aliases)));
     }
+
+    /**
+     * 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 (aliases.get(index) == null && noAliasesSpecified) {
+                List<AliasMetaData> previous = mapBuilder.put(index, Collections.emptyList());
+                assert previous == null;
+            }
+        }
+        return mapBuilder.build();
+    }
+
 }

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

@@ -265,8 +265,7 @@ public ImmutableOpenMap<String, List<AliasMetaData>> findAliases(final String[]
 
         boolean matchAllAliases = matchAllAliases(aliases);
         ImmutableOpenMap.Builder<String, List<AliasMetaData>> mapBuilder = ImmutableOpenMap.builder();
-        Iterable<String> intersection = HppcMaps.intersection(ObjectHashSet.from(concreteIndices), indices.keys());
-        for (String index : intersection) {
+        for (String index : concreteIndices) {
             IndexMetaData indexMetaData = indices.get(index);
             List<AliasMetaData> filteredValues = new ArrayList<>();
             for (ObjectCursor<AliasMetaData> cursor : indexMetaData.getAliases().values()) {
@@ -276,11 +275,11 @@ public ImmutableOpenMap<String, List<AliasMetaData>> findAliases(final String[]
                 }
             }
 
-            if (!filteredValues.isEmpty()) {
+            if (filteredValues.isEmpty() == false) {
                 // Make the list order deterministic
                 CollectionUtil.timSort(filteredValues, Comparator.comparing(AliasMetaData::alias));
+                mapBuilder.put(index, Collections.unmodifiableList(filteredValues));
             }
-            mapBuilder.put(index, Collections.unmodifiableList(filteredValues));
         }
         return mapBuilder.build();
     }

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));
+    }
+
+}

server/src/test/java/org/elasticsearch/aliases/IndexAliasesIT.java

@@ -570,24 +570,20 @@ public void testIndicesGetAliases() throws Exception {
         logger.info("--> getting alias1");
         GetAliasesResponse getResponse = admin().indices().prepareGetAliases("alias1").get();
         assertThat(getResponse, notNullValue());
-        assertThat(getResponse.getAliases().size(), equalTo(5));
+        assertThat(getResponse.getAliases().size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").get(0), notNullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).alias(), equalTo("alias1"));
         assertThat(getResponse.getAliases().get("foobar").get(0).getFilter(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getIndexRouting(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getSearchRouting(), nullValue());
-        assertTrue(getResponse.getAliases().get("test").isEmpty());
-        assertTrue(getResponse.getAliases().get("test123").isEmpty());
-        assertTrue(getResponse.getAliases().get("foobarbaz").isEmpty());
-        assertTrue(getResponse.getAliases().get("bazbar").isEmpty());
         AliasesExistResponse existsResponse = admin().indices().prepareAliasesExist("alias1").get();
         assertThat(existsResponse.exists(), equalTo(true));
 
         logger.info("--> getting all aliases that start with alias*");
         getResponse = admin().indices().prepareGetAliases("alias*").get();
         assertThat(getResponse, notNullValue());
-        assertThat(getResponse.getAliases().size(), equalTo(5));
+        assertThat(getResponse.getAliases().size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").size(), equalTo(2));
         assertThat(getResponse.getAliases().get("foobar").get(0), notNullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).alias(), equalTo("alias1"));
@@ -599,10 +595,6 @@ public void testIndicesGetAliases() throws Exception {
         assertThat(getResponse.getAliases().get("foobar").get(1).getFilter(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(1).getIndexRouting(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(1).getSearchRouting(), nullValue());
-        assertTrue(getResponse.getAliases().get("test").isEmpty());
-        assertTrue(getResponse.getAliases().get("test123").isEmpty());
-        assertTrue(getResponse.getAliases().get("foobarbaz").isEmpty());
-        assertTrue(getResponse.getAliases().get("bazbar").isEmpty());
         existsResponse = admin().indices().prepareAliasesExist("alias*").get();
         assertThat(existsResponse.exists(), equalTo(true));
 
@@ -687,13 +679,12 @@ public void testIndicesGetAliases() throws Exception {
         logger.info("--> getting f* for index *bar");
         getResponse = admin().indices().prepareGetAliases("f*").addIndices("*bar").get();
         assertThat(getResponse, notNullValue());
-        assertThat(getResponse.getAliases().size(), equalTo(2));
+        assertThat(getResponse.getAliases().size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").get(0), notNullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).alias(), equalTo("foo"));
         assertThat(getResponse.getAliases().get("foobar").get(0).getFilter(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getIndexRouting(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getSearchRouting(), nullValue());
-        assertTrue(getResponse.getAliases().get("bazbar").isEmpty());
         existsResponse = admin().indices().prepareAliasesExist("f*")
                 .addIndices("*bar").get();
         assertThat(existsResponse.exists(), equalTo(true));
@@ -702,14 +693,13 @@ public void testIndicesGetAliases() throws Exception {
         logger.info("--> getting f* for index *bac");
         getResponse = admin().indices().prepareGetAliases("foo").addIndices("*bac").get();
         assertThat(getResponse, notNullValue());
-        assertThat(getResponse.getAliases().size(), equalTo(2));
+        assertThat(getResponse.getAliases().size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").size(), equalTo(1));
         assertThat(getResponse.getAliases().get("foobar").get(0), notNullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).alias(), equalTo("foo"));
         assertThat(getResponse.getAliases().get("foobar").get(0).getFilter(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getIndexRouting(), nullValue());
         assertThat(getResponse.getAliases().get("foobar").get(0).getSearchRouting(), nullValue());
-        assertTrue(getResponse.getAliases().get("bazbar").isEmpty());
         existsResponse = admin().indices().prepareAliasesExist("foo")
                 .addIndices("*bac").get();
         assertThat(existsResponse.exists(), equalTo(true));
@@ -727,6 +717,19 @@ public void testIndicesGetAliases() throws Exception {
                 .addIndices("foobar").get();
         assertThat(existsResponse.exists(), equalTo(true));
 
+        for (String aliasName : new String[]{null, "_all", "*"}) {
+            logger.info("--> getting {} alias for index foobar", aliasName);
+            getResponse = aliasName != null ? admin().indices().prepareGetAliases(aliasName).addIndices("foobar").get() :
+                admin().indices().prepareGetAliases().addIndices("foobar").get();
+            assertThat(getResponse, notNullValue());
+            assertThat(getResponse.getAliases().size(), equalTo(1));
+            assertThat(getResponse.getAliases().get("foobar").size(), equalTo(4));
+            assertThat(getResponse.getAliases().get("foobar").get(0).alias(), equalTo("alias1"));
+            assertThat(getResponse.getAliases().get("foobar").get(1).alias(), equalTo("alias2"));
+            assertThat(getResponse.getAliases().get("foobar").get(2).alias(), equalTo("bac"));
+            assertThat(getResponse.getAliases().get("foobar").get(3).alias(), equalTo("foo"));
+        }
+
         // alias at work again
         logger.info("--> getting * for index *bac");
         getResponse = admin().indices().prepareGetAliases("*").addIndices("*bac").get();

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authz/IndicesAndAliasesResolver.java

@@ -200,7 +200,7 @@ ResolvedIndices resolveIndicesAndAliases(IndicesRequest indicesRequest, MetaData
             if (aliasesRequest.expandAliasesWildcards()) {
                 List<String> aliases = replaceWildcardsWithAuthorizedAliases(aliasesRequest.aliases(),
                         loadAuthorizedAliases(authorizedIndices.get(), metaData));
-                aliasesRequest.aliases(aliases.toArray(new String[aliases.size()]));
+                aliasesRequest.replaceAliases(aliases.toArray(new String[aliases.size()]));
             }
             if (indicesReplacedWithNoIndices) {
                 if (indicesRequest instanceof GetAliasesRequest == false) {