Retry point in time on other copy when possible

docs/reference/search/point-in-time-api.asciidoc

@@ -38,7 +38,7 @@ POST /_search <1>
         }
     },
     "pit": {
-	    "id":  "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWICBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <2>
+	    "id":  "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <2>
 	    "keep_alive": "1m"  <3>
     }
 }
@@ -99,7 +99,7 @@ as soon as they are no longer used in search requests.
 ---------------------------------------
 DELETE /_pit
 {
-    "id" : "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWIBBXV1aWQyAAA="
+    "id" : "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="
 }
 ---------------------------------------
 // TEST[catch:missing]

docs/reference/search/point-in-time.asciidoc

@@ -35,7 +35,7 @@ POST /_search <1>
         }
     },
     "pit": {
-	    "id":  "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWICBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <2>
+	    "id":  "48myAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwEAA2lkeAV1dWlkMQIGbm9kZV8xAAAAAAAAAAABAWEBAANpZHkFdXVpZDIqBm5vZGVfMgAAAAAAAAAADAFiAQACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <2>
 	    "keep_alive": "1m"  <3>
     }
 }
@@ -95,7 +95,7 @@ as soon as they are no longer used in search requests.
 ---------------------------------------
 DELETE /_pit
 {
-    "id" : "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWIBBXV1aWQyAAA="
+    "id" : "48myAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwEAA2lkeAV1dWlkMQIGbm9kZV8xAAAAAAAAAAABAWEBAANpZHkFdXVpZDIqBm5vZGVfMgAAAAAAAAAADAFiAQACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="
 }
 ---------------------------------------
 // TEST[catch:missing]

docs/reference/search/search-your-data/paginate-search-results.asciidoc

@@ -62,10 +62,10 @@ The API returns a PIT ID.
 [source,console-result]
 ----
 {
-  "id": "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWICBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="
+  "id": "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="
 }
 ----
-// TESTRESPONSE[s/"id": "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWICBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="/"id": $body.id/]
+// TESTRESPONSE[s/"id": "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="/"id": $body.id/]
 
 To get the first page of results, submit a search request with a `sort`
 argument. If using a PIT, specify the PIT ID in the `pit.id` parameter and omit
@@ -86,7 +86,7 @@ GET /_search
     }
   },
   "pit": {
-	    "id":  "46ToAwMDaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQNpZHkFdXVpZDIrBm5vZGVfMwAAAAAAAAAAKgFjA2lkeQV1dWlkMioGbm9kZV8yAAAAAAAAAAAMAWICBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <1>
+	    "id":  "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <1>
 	    "keep_alive": "1m"
   },
   "sort": [ <2>
@@ -106,7 +106,7 @@ a PIT, the response's `pit_id` parameter contains an updated PIT ID.
 [source,console-result]
 ----
 {
-  "pit_id" : "46ToAwEPbXktaW5kZXgtMDAwMDAxFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAFldicVdzOFFtVHZTZDFoWWowTGkwS0EAAAAAAAAAAAQURzZzcUszUUJ5U1NMX3Jyak5ET0wBFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAAA==", <1>
+  "pit_id" : "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <1>
   "took" : 17,
   "timed_out" : false,
   "_shards" : ...,
@@ -150,7 +150,7 @@ GET /_search
     }
   },
   "pit": {
-	    "id":  "46ToAwEPbXktaW5kZXgtMDAwMDAxFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAFldicVdzOFFtVHZTZDFoWWowTGkwS0EAAAAAAAAAAAQURzZzcUszUUJ5U1NMX3Jyak5ET0wBFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAAA==", <1>
+	    "id":  "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA==", <1>
 	    "keep_alive": "1m"
   },
   "sort": [
@@ -178,7 +178,7 @@ When you're finished, you should delete your PIT.
 ----
 DELETE /_pit
 {
-    "id" : "46ToAwEPbXktaW5kZXgtMDAwMDAxFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAFldicVdzOFFtVHZTZDFoWWowTGkwS0EAAAAAAAAAAAQURzZzcUszUUJ5U1NMX3Jyak5ET0wBFnVzaTVuenpUVGQ2TFNheUxVUG5LVVEAAA=="
+    "id" : "46ToAwMDaWR5BXV1aWQyKwZub2RlXzMAAAAAAAAAACoBYwADaWR4BXV1aWQxAgZub2RlXzEAAAAAAAAAAAEBYQADaWR5BXV1aWQyKgZub2RlXzIAAAAAAAAAAAwBYgACBXV1aWQyAAAFdXVpZDEAAQltYXRjaF9hbGw_gAAAAA=="
 }
 ----
 // TEST[catch:missing]

server/src/main/java/org/elasticsearch/action/search/AbstractSearchAsyncAction.java

@@ -38,11 +38,14 @@
 import org.elasticsearch.common.util.concurrent.AbstractRunnable;
 import org.elasticsearch.common.util.concurrent.AtomicArray;
 import org.elasticsearch.index.shard.ShardId;
+import org.elasticsearch.search.SearchContextMissingException;
 import org.elasticsearch.search.SearchPhaseResult;
 import org.elasticsearch.search.SearchShardTarget;
+import org.elasticsearch.search.builder.PointInTimeBuilder;
 import org.elasticsearch.search.internal.AliasFilter;
 import org.elasticsearch.search.internal.InternalSearchResponse;
 import org.elasticsearch.search.internal.SearchContext;
+import org.elasticsearch.search.internal.ShardSearchContextId;
 import org.elasticsearch.search.internal.ShardSearchRequest;
 import org.elasticsearch.tasks.TaskCancelledException;
 import org.elasticsearch.transport.Transport;
@@ -478,7 +481,7 @@ public final void onShardFailure(final int shardIndex, SearchShardTarget shardTa
             } else {
                 // the failure is already present, try and not override it with an exception that is less meaningless
                 // for example, getting illegal shard state
-                if (TransportActions.isReadOverrideException(e)) {
+                if (TransportActions.isReadOverrideException(e) && (e instanceof SearchContextMissingException == false)) {
                     shardFailures.set(shardIndex, new ShardSearchFailure(e, shardTarget));
                 }
             }
@@ -567,6 +570,16 @@ public final SearchRequest getRequest() {
         return request;
     }
 
+    @Override
+    public boolean isPartOfPointInTime(ShardSearchContextId contextId) {
+        final PointInTimeBuilder pointInTimeBuilder = request.pointInTimeBuilder();
+        if (pointInTimeBuilder != null) {
+            return request.pointInTimeBuilder().getSearchContextId(searchTransportService.getNamedWriteableRegistry()).contains(contextId);
+        } else {
+            return false;
+        }
+    }
+
     protected final SearchResponse buildSearchResponse(InternalSearchResponse internalSearchResponse, ShardSearchFailure[] failures,
                                                        String scrollId, String searchContextId) {
         int numSuccess = successfulOps.get();
@@ -598,7 +611,7 @@ public void sendSearchResponse(InternalSearchResponse internalSearchResponse, At
                 searchContextId = SearchContextId.encode(queryResults.asList(), aliasFilter, minNodeVersion);
             } else {
                 if (request.source() != null && request.source().pointInTimeBuilder() != null) {
-                    searchContextId = request.source().pointInTimeBuilder().getId();
+                    searchContextId = request.source().pointInTimeBuilder().getEncodedId();
                 } else {
                     searchContextId = null;
                 }
@@ -619,21 +632,19 @@ public final void onPhaseFailure(SearchPhase phase, String msg, Throwable cause)
      * @param exception the exception explaining or causing the phase failure
      */
     private void raisePhaseFailure(SearchPhaseExecutionException exception) {
-        // we don't release persistent readers (point in time).
-        if (request.pointInTimeBuilder() == null) {
-            results.getSuccessfulResults().forEach((entry) -> {
-                if (entry.getContextId() != null) {
-                    try {
-                        SearchShardTarget searchShardTarget = entry.getSearchShardTarget();
-                        Transport.Connection connection = getConnection(searchShardTarget.getClusterAlias(), searchShardTarget.getNodeId());
-                        sendReleaseSearchContext(entry.getContextId(), connection, searchShardTarget.getOriginalIndices());
-                    } catch (Exception inner) {
-                        inner.addSuppressed(exception);
-                        logger.trace("failed to release context", inner);
-                    }
+        results.getSuccessfulResults().forEach((entry) -> {
+            // Do not release search contexts that are part of the point in time
+            if (entry.getContextId() != null && isPartOfPointInTime(entry.getContextId()) == false) {
+                try {
+                    SearchShardTarget searchShardTarget = entry.getSearchShardTarget();
+                    Transport.Connection connection = getConnection(searchShardTarget.getClusterAlias(), searchShardTarget.getNodeId());
+                    sendReleaseSearchContext(entry.getContextId(), connection, searchShardTarget.getOriginalIndices());
+                } catch (Exception inner) {
+                    inner.addSuppressed(exception);
+                    logger.trace("failed to release context", inner);
                 }
-            });
-        }
+            }
+        });
         Releasables.close(releasables);
         listener.onFailure(exception);
     }

server/src/main/java/org/elasticsearch/action/search/DfsQueryPhase.java

@@ -100,7 +100,7 @@ public void onFailure(Exception exception) {
                             progressListener.notifyQueryFailure(shardIndex, searchShardTarget, exception);
                             counter.onFailure(shardIndex, searchShardTarget, exception);
                         } finally {
-                            if (context.getRequest().pointInTimeBuilder() == null) {
+                            if (context.isPartOfPointInTime(querySearchRequest.contextId()) == false) {
                                 // the query might not have been executed at all (for example because thread pool rejected
                                 // execution) and the search context that was created in dfs phase might not be released.
                                 // release it again to be in the safe side

server/src/main/java/org/elasticsearch/action/search/FetchSearchPhase.java

@@ -210,7 +210,7 @@ private void releaseIrrelevantSearchContext(QuerySearchResult queryResult) {
         // or using a PIT and if it has at least one hit that didn't make it to the global topDocs
         if (queryResult.hasSearchContext()
                 && context.getRequest().scroll() == null
-                && context.getRequest().pointInTimeBuilder() == null) {
+                && (context.isPartOfPointInTime(queryResult.getContextId()) == false)) {
             try {
                 SearchShardTarget searchShardTarget = queryResult.getSearchShardTarget();
                 Transport.Connection connection = context.getConnection(searchShardTarget.getClusterAlias(), searchShardTarget.getNodeId());

server/src/main/java/org/elasticsearch/action/search/SearchContextId.java

@@ -32,6 +32,7 @@
 import org.elasticsearch.search.SearchPhaseResult;
 import org.elasticsearch.search.SearchShardTarget;
 import org.elasticsearch.search.internal.AliasFilter;
+import org.elasticsearch.search.internal.ShardSearchContextId;
 import org.elasticsearch.transport.RemoteClusterAware;
 
 import java.io.IOException;
@@ -43,14 +44,17 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
 
-public class SearchContextId {
+public final class SearchContextId {
     private final Map<ShardId, SearchContextIdForNode> shards;
     private final Map<String, AliasFilter> aliasFilter;
+    private transient Set<ShardSearchContextId> contextIds;
 
-    private SearchContextId(Map<ShardId, SearchContextIdForNode> shards, Map<String, AliasFilter> aliasFilter) {
+    SearchContextId(Map<ShardId, SearchContextIdForNode> shards, Map<String, AliasFilter> aliasFilter) {
         this.shards = shards;
         this.aliasFilter = aliasFilter;
+        this.contextIds = shards.values().stream().map(SearchContextIdForNode::getSearchContextId).collect(Collectors.toSet());
     }
 
     public Map<ShardId, SearchContextIdForNode> shards() {
@@ -61,6 +65,10 @@ public Map<String, AliasFilter> aliasFilter() {
         return aliasFilter;
     }
 
+    public boolean contains(ShardSearchContextId contextId) {
+        return contextIds.contains(contextId);
+    }
+
     public static String encode(List<SearchPhaseResult> searchPhaseResults, Map<String, AliasFilter> aliasFilter, Version version) {
         final Map<ShardId, SearchContextIdForNode> shards = new HashMap<>();
         for (SearchPhaseResult searchPhaseResult : searchPhaseResults) {

server/src/main/java/org/elasticsearch/action/search/SearchPhaseContext.java

@@ -58,6 +58,12 @@ interface SearchPhaseContext extends Executor {
      */
     SearchRequest getRequest();
 
+    /**
+     * Checks if the given context id is part of the point in time of this search (if exists).
+     * We should not release search contexts that belong to the point in time during or after searches.
+     */
+    boolean isPartOfPointInTime(ShardSearchContextId contextId);
+
     /**
      * Builds and sends the final search response back to the user.
      *
@@ -108,6 +114,7 @@ interface SearchPhaseContext extends Executor {
     default void sendReleaseSearchContext(ShardSearchContextId contextId,
                                           Transport.Connection connection,
                                           OriginalIndices originalIndices) {
+        assert isPartOfPointInTime(contextId) == false : "Must not release point in time context [" + contextId + "]";
         if (connection != null) {
             getSearchTransport().sendFreeContext(connection, contextId, originalIndices);
         }

server/src/main/java/org/elasticsearch/action/search/SearchTransportService.java

@@ -32,6 +32,7 @@
 import org.elasticsearch.client.node.NodeClient;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.Nullable;
+import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
@@ -438,4 +439,8 @@ public void cancelSearchTask(SearchTask task, String reason) {
         // force the origin to execute the cancellation as a system user
         new OriginSettingClient(client, GetTaskAction.TASKS_ORIGIN).admin().cluster().cancelTasks(req, ActionListener.wrap(() -> {}));
     }
+
+    public NamedWriteableRegistry getNamedWriteableRegistry() {
+        return client.getNamedWriteableRegistry();
+    }
 }

server/src/main/java/org/elasticsearch/action/search/TransportSearchAction.java

@@ -38,6 +38,7 @@
 import org.elasticsearch.cluster.routing.GroupShardsIterator;
 import org.elasticsearch.cluster.routing.OperationRouting;
 import org.elasticsearch.cluster.routing.ShardIterator;
+import org.elasticsearch.cluster.routing.ShardRouting;
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.Strings;
@@ -284,7 +285,7 @@ private void executeRequest(Task task, SearchRequest searchRequest,
             final SearchContextId searchContext;
             final Map<String, OriginalIndices> remoteClusterIndices;
             if (searchRequest.pointInTimeBuilder() != null) {
-                searchContext = SearchContextId.decode(namedWriteableRegistry, searchRequest.pointInTimeBuilder().getId());
+                searchContext = searchRequest.pointInTimeBuilder().getSearchContextId(namedWriteableRegistry);
                 remoteClusterIndices = getIndicesFromSearchContexts(searchContext, searchRequest.indicesOptions());
             } else {
                 searchContext = null;
@@ -581,7 +582,15 @@ static List<SearchShardIterator> getRemoteShardsIteratorFromPointInTime(Map<Stri
                 final String clusterAlias = entry.getKey();
                 final SearchContextIdForNode perNode = searchContextId.shards().get(shardId);
                 assert clusterAlias.equals(perNode.getClusterAlias()) : clusterAlias + " != " + perNode.getClusterAlias();
-                final List<String> targetNodes = Collections.singletonList(perNode.getNode());
+                final List<String> targetNodes = new ArrayList<>(group.getShards().length);
+                targetNodes.add(perNode.getNode());
+                if (perNode.getSearchContextId().getSearcherId() != null) {
+                    for (ShardRouting shard : group.getShards()) {
+                        if (shard.currentNodeId().equals(perNode.getNode()) == false) {
+                            targetNodes.add(shard.currentNodeId());
+                        }
+                    }
+                }
                 SearchShardIterator shardIterator = new SearchShardIterator(clusterAlias, shardId, targetNodes,
                     remoteClusterIndices.get(clusterAlias), perNode.getSearchContextId(), searchContextKeepAlive);
                 remoteShardIterators.add(shardIterator);
@@ -915,8 +924,16 @@ static List<SearchShardIterator> getLocalLocalShardsIteratorFromPointInTime(Clus
             final SearchContextIdForNode perNode = entry.getValue();
             if (Strings.isEmpty(perNode.getClusterAlias())) {
                 final ShardId shardId = entry.getKey();
-                OperationRouting.getShards(clusterState, shardId);
-                final List<String> targetNodes = Collections.singletonList(perNode.getNode());
+                final ShardIterator shards = OperationRouting.getShards(clusterState, shardId);
+                final List<String> targetNodes = new ArrayList<>(shards.size());
+                targetNodes.add(perNode.getNode());
+                if (perNode.getSearchContextId().getSearcherId() != null) {
+                    for (ShardRouting shard : shards) {
+                        if (shard.currentNodeId().equals(perNode.getNode()) == false) {
+                            targetNodes.add(shard.currentNodeId());
+                        }
+                    }
+                }
                 iterators.add(new SearchShardIterator(localClusterAlias, shardId, targetNodes, originalIndices,
                     perNode.getSearchContextId(), keepAlive));
             }

server/src/main/java/org/elasticsearch/rest/action/search/RestSearchAction.java

@@ -337,7 +337,7 @@ static void preparePointInTime(SearchRequest request, RestRequest restRequest, N
             indicesOptions.ignoreUnavailable(), indicesOptions.allowNoIndices(), false, false, false,
             true, true, indicesOptions.ignoreThrottled());
         request.indicesOptions(stricterIndicesOptions);
-        final SearchContextId searchContextId = SearchContextId.decode(namedWriteableRegistry, request.pointInTimeBuilder().getId());
+        final SearchContextId searchContextId = request.pointInTimeBuilder().getSearchContextId(namedWriteableRegistry);
         request.indices(searchContextId.getActualIndices());
     }