Use GetSnapshotsResponse.Response in GroupedActionListener

Author: Andrey Ershov

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/get/GetSnapshotsResponse.java

@@ -33,6 +33,7 @@
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -53,17 +54,13 @@ public class GetSnapshotsResponse extends ActionResponse implements ToXContentOb
                 (p, c) -> Response.fromXContent(p), new ParseField("responses"));
     }
 
-    public GetSnapshotsResponse(Map<String, List<SnapshotInfo>> successfulResponses, Map<String, ElasticsearchException> failedResponses) {
-        this.successfulResponses = successfulResponses;
-        this.failedResponses = failedResponses;
-    }
 
-    private static class Response {
-        String repository;
-        List<SnapshotInfo> snapshots;
-        ElasticsearchException error;
+    public static class Response {
+        private String repository;
+        private List<SnapshotInfo> snapshots;
+        private ElasticsearchException error;
 
-        static final ConstructingObjectParser<Response, Void> RESPONSE_PARSER =
+        private static final ConstructingObjectParser<Response, Void> RESPONSE_PARSER =
                 new ConstructingObjectParser<>(Response.class.getName(), true,
                         (args) -> new Response((String) args[0],
                                 (List<SnapshotInfo>) args[1], (ElasticsearchException) args[2]));
@@ -76,21 +73,29 @@ private static class Response {
                     (p, c) -> ElasticsearchException.fromXContent(p), new ParseField("error"));
         }
 
-        Response(String repository, List<SnapshotInfo> snapshots, ElasticsearchException error) {
+        private Response(String repository, List<SnapshotInfo> snapshots, ElasticsearchException error) {
             this.repository = repository;
             this.snapshots = snapshots;
             this.error = error;
         }
 
-        static Response fromXContent(XContentParser parser) throws IOException {
+        public static Response snapshots(String repository, List<SnapshotInfo> snapshots) {
+            return new Response(repository, snapshots, null);
+        }
+
+        public static Response error(String repository, ElasticsearchException error) {
+            return new Response(repository, null, error);
+        }
+
+        private static Response fromXContent(XContentParser parser) throws IOException {
             return RESPONSE_PARSER.parse(parser, null);
         }
     }
 
     private Map<String, List<SnapshotInfo>> successfulResponses = Collections.emptyMap();
     private Map<String, ElasticsearchException> failedResponses = Collections.emptyMap();
 
-    private GetSnapshotsResponse(List<Response> responses) {
+    public GetSnapshotsResponse(Collection<Response> responses) {
         this.successfulResponses = new HashMap<>();
         this.failedResponses = new HashMap<>();
         for (Response response : responses) {

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/get/TransportGetSnapshotsAction.java

@@ -106,42 +106,22 @@ protected void masterOperation(final GetSnapshotsRequest request, final ClusterS
 
     private void getMultipleReposSnapshotInfo(List<RepositoryMetaData> repos, String[] snapshots, boolean ignoreUnavailable,
                                               boolean verbose, ActionListener<GetSnapshotsResponse> listener) {
-        GroupedActionListener<Tuple<String, Tuple<List<SnapshotInfo>, ElasticsearchException>>> groupedActionListener =
+        final GroupedActionListener<GetSnapshotsResponse.Response> groupedActionListener =
                 new GroupedActionListener<>(
                         ActionListener.map(listener, responses -> {
                             assert repos.size() == responses.size();
-
-                            Map<String, List<SnapshotInfo>> successfulResponses = new HashMap<>();
-                            Map<String, ElasticsearchException> failedResponses = new HashMap<>();
-
-                            Iterator<Tuple<String, Tuple<List<SnapshotInfo>, ElasticsearchException>>> it = responses.iterator();
-
-                            while (it.hasNext()) {
-                                Tuple<String, Tuple<List<SnapshotInfo>, ElasticsearchException>> response = it.next();
-                                String repo = response.v1();
-                                Tuple<List<SnapshotInfo>, ElasticsearchException> result = response.v2();
-                                if (result.v1() != null) {
-                                    assert result.v2() == null;
-                                    successfulResponses.put(repo, result.v1());
-                                } else {
-                                    assert result.v2() != null;
-                                    failedResponses.put(repo, result.v2());
-                                }
-                            }
-
-                            return new GetSnapshotsResponse(successfulResponses, failedResponses);
+                            return new GetSnapshotsResponse(responses);
                         }), repos.size());
 
         // run concurrently for all repos on GENERIC thread pool
         for (final RepositoryMetaData repo : repos) {
             threadPool.executor(ThreadPool.Names.GENERIC).execute(
                     () -> {
-                        // Unfortunately, there is no Either in Java, so we use Tuple with only one value set
                         try {
-                            groupedActionListener.onResponse(Tuple.tuple(repo.name(),
-                                    Tuple.tuple(getSingleRepoSnapshotInfo(repo.name(), snapshots, ignoreUnavailable, verbose), null)));
+                            groupedActionListener.onResponse(GetSnapshotsResponse.Response.snapshots(
+                                    repo.name(), getSingleRepoSnapshotInfo(repo.name(), snapshots, ignoreUnavailable, verbose)));
                         } catch (ElasticsearchException e) {
-                            groupedActionListener.onResponse(Tuple.tuple(repo.name(), Tuple.tuple(null, e)));
+                            groupedActionListener.onResponse(GetSnapshotsResponse.Response.error(repo.name(), e));
                         }
                     });
         }

server/src/test/java/org/elasticsearch/action/admin/cluster/snapshots/get/GetSnapshotsResponseTests.java

@@ -36,7 +36,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
@@ -86,22 +85,21 @@ private List<SnapshotInfo> createSnapshotInfos() {
 
     private GetSnapshotsResponse createTestInstance() {
         Set<String> repositories = new HashSet<>();
-        Map<String, List<SnapshotInfo>> successfulResponses = new HashMap<>();
-        Map<String, ElasticsearchException> failedResponses = new HashMap<>();
+        List<GetSnapshotsResponse.Response> responses = new ArrayList<>();
 
         for (int i = 0; i < randomIntBetween(0, 5); i++) {
             String repository = randomValueOtherThanMany(r -> repositories.contains(r), () -> randomAlphaOfLength(10));
             repositories.add(repository);
-            successfulResponses.put(repository, createSnapshotInfos());
+            responses.add(GetSnapshotsResponse.Response.snapshots(repository, createSnapshotInfos()));
         }
 
         for (int i = 0; i < randomIntBetween(0, 5); i++) {
             String repository = randomValueOtherThanMany(r -> repositories.contains(r), () -> randomAlphaOfLength(10));
             repositories.add(repository);
-            failedResponses.put(repository, new ElasticsearchException(randomAlphaOfLength(10)));
+            responses.add(GetSnapshotsResponse.Response.error(repository, new ElasticsearchException(randomAlphaOfLength(10))));
         }
 
-        return new GetSnapshotsResponse(successfulResponses, failedResponses);
+        return new GetSnapshotsResponse(responses);
     }
 
     public void testSerialization() throws IOException {