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* the Apache License, Version 2.0 (the "License"); you may
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* 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
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package org.elasticsearch.action.search;
import com.carrotsearch.hppc.IntArrayList;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.NoShardAvailableActionException;
import org.elasticsearch.action.support.TransportActions;
import org.elasticsearch.cluster.ClusterService;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.block.ClusterBlockLevel;
import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.cluster.node.DiscoveryNodes;
import org.elasticsearch.cluster.routing.GroupShardsIterator;
import org.elasticsearch.cluster.routing.ShardIterator;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.logging.ESLogger;
import org.elasticsearch.common.util.concurrent.AtomicArray;
import org.elasticsearch.search.SearchPhaseResult;
import org.elasticsearch.search.SearchShardTarget;
import org.elasticsearch.search.action.SearchServiceTransportAction;
import org.elasticsearch.search.controller.SearchPhaseController;
import org.elasticsearch.search.fetch.ShardFetchSearchRequest;
import org.elasticsearch.search.internal.InternalSearchResponse;
import org.elasticsearch.search.internal.ShardSearchTransportRequest;
import org.elasticsearch.search.query.QuerySearchResult;
import org.elasticsearch.search.query.QuerySearchResultProvider;
import org.elasticsearch.threadpool.ThreadPool;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.atomic.AtomicInteger;
import static org.elasticsearch.action.search.TransportSearchHelper.internalSearchRequest;
abstract class AbstractSearchAsyncAction<FirstResult extends SearchPhaseResult> extends AbstractAsyncAction {
protected final ESLogger logger;
protected final SearchServiceTransportAction searchService;
protected final SearchPhaseController searchPhaseController;
protected final ThreadPool threadPool;
private final IndexNameExpressionResolver indexNameExpressionResolver;
protected final ActionListener<SearchResponse> listener;
protected final GroupShardsIterator shardsIts;
protected final SearchRequest request;
protected final ClusterState clusterState;
protected final DiscoveryNodes nodes;
protected final int expectedSuccessfulOps;
private final int expectedTotalOps;
protected final AtomicInteger successfulOps = new AtomicInteger();
private final AtomicInteger totalOps = new AtomicInteger();
protected final AtomicArray<FirstResult> firstResults;
private volatile AtomicArray<ShardSearchFailure> shardFailures;
private final Object shardFailuresMutex = new Object();
protected volatile ScoreDoc[] sortedShardList;
protected AbstractSearchAsyncAction(ESLogger logger, SearchServiceTransportAction searchService, ClusterService clusterService,
IndexNameExpressionResolver indexNameExpressionResolver,
SearchPhaseController searchPhaseController, ThreadPool threadPool,
SearchRequest request, ActionListener<SearchResponse> listener) {
this.logger = logger;
this.searchService = searchService;
this.indexNameExpressionResolver = indexNameExpressionResolver;
this.searchPhaseController = searchPhaseController;
this.threadPool = threadPool;
this.request = request;
this.listener = listener;
this.clusterState = clusterService.state();
nodes = clusterState.nodes();
clusterState.blocks().globalBlockedRaiseException(ClusterBlockLevel.READ);
// TODO: I think startTime() should become part of ActionRequest and that should be used both for index name
// date math expressions and $now in scripts. This way all apis will deal with now in the same way instead
// of just for the _search api
String[] concreteIndices = indexNameExpressionResolver.concreteIndices(clusterState, request.indicesOptions(), startTime(), request.indices());
for (String index : concreteIndices) {
clusterState.blocks().indexBlockedRaiseException(ClusterBlockLevel.READ, index);
}
Map<String, Set<String>> routingMap = indexNameExpressionResolver.resolveSearchRouting(clusterState, request.routing(), request.indices());
shardsIts = clusterService.operationRouting().searchShards(clusterState, concreteIndices, routingMap, request.preference());
expectedSuccessfulOps = shardsIts.size();
// we need to add 1 for non active partition, since we count it in the total!
expectedTotalOps = shardsIts.totalSizeWith1ForEmpty();
firstResults = new AtomicArray<>(shardsIts.size());
}
public void start() {
if (expectedSuccessfulOps == 0) {
// no search shards to search on, bail with empty response (it happens with search across _all with no indices around and consistent with broadcast operations)
listener.onResponse(new SearchResponse(InternalSearchResponse.empty(), null, 0, 0, buildTookInMillis(), ShardSearchFailure.EMPTY_ARRAY));
return;
}
int shardIndex = -1;
for (final ShardIterator shardIt : shardsIts) {
shardIndex++;
final ShardRouting shard = shardIt.nextOrNull();
if (shard != null) {
performFirstPhase(shardIndex, shardIt, shard);
} else {
// really, no shards active in this group
onFirstPhaseResult(shardIndex, null, null, shardIt, new NoShardAvailableActionException(shardIt.shardId()));
}
}
}
void performFirstPhase(final int shardIndex, final ShardIterator shardIt, final ShardRouting shard) {
if (shard == null) {
// no more active shards... (we should not really get here, but just for safety)
onFirstPhaseResult(shardIndex, null, null, shardIt, new NoShardAvailableActionException(shardIt.shardId()));
} else {
final DiscoveryNode node = nodes.get(shard.currentNodeId());
if (node == null) {
onFirstPhaseResult(shardIndex, shard, null, shardIt, new NoShardAvailableActionException(shardIt.shardId()));
} else {
String[] filteringAliases = indexNameExpressionResolver.filteringAliases(clusterState, shard.index(), request.indices());
sendExecuteFirstPhase(node, internalSearchRequest(shard, shardsIts.size(), request, filteringAliases, startTime()), new ActionListener<FirstResult>() {
@Override
public void onResponse(FirstResult result) {
onFirstPhaseResult(shardIndex, shard, result, shardIt);
}
@Override
public void onFailure(Throwable t) {
onFirstPhaseResult(shardIndex, shard, node.id(), shardIt, t);
}
});
}
}
}
void onFirstPhaseResult(int shardIndex, ShardRouting shard, FirstResult result, ShardIterator shardIt) {
result.shardTarget(new SearchShardTarget(shard.currentNodeId(), shard.index(), shard.id()));
processFirstPhaseResult(shardIndex, result);
// we need to increment successful ops first before we compare the exit condition otherwise if we
// are fast we could concurrently update totalOps but then preempt one of the threads which can
// cause the successor to read a wrong value from successfulOps if second phase is very fast ie. count etc.
successfulOps.incrementAndGet();
// increment all the "future" shards to update the total ops since we some may work and some may not...
// and when that happens, we break on total ops, so we must maintain them
final int xTotalOps = totalOps.addAndGet(shardIt.remaining() + 1);
if (xTotalOps == expectedTotalOps) {
try {
innerMoveToSecondPhase();
} catch (Throwable e) {
if (logger.isDebugEnabled()) {
logger.debug(shardIt.shardId() + ": Failed to execute [" + request + "] while moving to second phase", e);
}
raiseEarlyFailure(new ReduceSearchPhaseException(firstPhaseName(), "", e, buildShardFailures()));
}
} else if (xTotalOps > expectedTotalOps) {
raiseEarlyFailure(new IllegalStateException("unexpected higher total ops [" + xTotalOps + "] compared to expected [" + expectedTotalOps + "]"));
}
}
void onFirstPhaseResult(final int shardIndex, @Nullable ShardRouting shard, @Nullable String nodeId, final ShardIterator shardIt, Throwable t) {
// we always add the shard failure for a specific shard instance
// we do make sure to clean it on a successful response from a shard
SearchShardTarget shardTarget = new SearchShardTarget(nodeId, shardIt.shardId().getIndex(), shardIt.shardId().getId());
addShardFailure(shardIndex, shardTarget, t);
if (totalOps.incrementAndGet() == expectedTotalOps) {
if (logger.isDebugEnabled()) {
if (t != null && !TransportActions.isShardNotAvailableException(t)) {
if (shard != null) {
logger.debug(shard.shortSummary() + ": Failed to execute [" + request + "]", t);
} else {
logger.debug(shardIt.shardId() + ": Failed to execute [" + request + "]", t);
}
} else if (logger.isTraceEnabled()) {
logger.trace("{}: Failed to execute [{}]", t, shard, request);
}
}
if (successfulOps.get() == 0) {
if (logger.isDebugEnabled()) {
logger.debug("All shards failed for phase: [{}]", t, firstPhaseName());
}
// no successful ops, raise an exception
raiseEarlyFailure(new SearchPhaseExecutionException(firstPhaseName(), "all shards failed", buildShardFailures()));
} else {
try {
innerMoveToSecondPhase();
} catch (Throwable e) {
raiseEarlyFailure(new ReduceSearchPhaseException(firstPhaseName(), "", e, buildShardFailures()));
}
}
} else {
final ShardRouting nextShard = shardIt.nextOrNull();
final boolean lastShard = nextShard == null;
// trace log this exception
if (logger.isTraceEnabled()) {
logger.trace(executionFailureMsg(shard, shardIt, request, lastShard), t);
}
if (!lastShard) {
try {
performFirstPhase(shardIndex, shardIt, nextShard);
} catch (Throwable t1) {
onFirstPhaseResult(shardIndex, shard, shard.currentNodeId(), shardIt, t1);
}
} else {
// no more shards active, add a failure
if (logger.isDebugEnabled() && !logger.isTraceEnabled()) { // do not double log this exception
if (t != null && !TransportActions.isShardNotAvailableException(t)) {
logger.debug(executionFailureMsg(shard, shardIt, request, lastShard), t);
}
}
}
}
}
private String executionFailureMsg(@Nullable ShardRouting shard, final ShardIterator shardIt, SearchRequest request, boolean lastShard) {
if (shard != null) {
return shard.shortSummary() + ": Failed to execute [" + request + "] lastShard [" + lastShard + "]";
} else {
return shardIt.shardId() + ": Failed to execute [" + request + "] lastShard [" + lastShard + "]";
}
}
protected final ShardSearchFailure[] buildShardFailures() {
AtomicArray<ShardSearchFailure> shardFailures = this.shardFailures;
if (shardFailures == null) {
return ShardSearchFailure.EMPTY_ARRAY;
}
List<AtomicArray.Entry<ShardSearchFailure>> entries = shardFailures.asList();
ShardSearchFailure[] failures = new ShardSearchFailure[entries.size()];
for (int i = 0; i < failures.length; i++) {
failures[i] = entries.get(i).value;
}
return failures;
}
protected final void addShardFailure(final int shardIndex, @Nullable SearchShardTarget shardTarget, Throwable t) {
// we don't aggregate shard failures on non active shards (but do keep the header counts right)
if (TransportActions.isShardNotAvailableException(t)) {
return;
}
// lazily create shard failures, so we can early build the empty shard failure list in most cases (no failures)
if (shardFailures == null) {
synchronized (shardFailuresMutex) {
if (shardFailures == null) {
shardFailures = new AtomicArray<>(shardsIts.size());
}
}
}
ShardSearchFailure failure = shardFailures.get(shardIndex);
if (failure == null) {
shardFailures.set(shardIndex, new ShardSearchFailure(t, shardTarget));
} 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(t)) {
shardFailures.set(shardIndex, new ShardSearchFailure(t, shardTarget));
}
}
}
private void raiseEarlyFailure(Throwable t) {
for (AtomicArray.Entry<FirstResult> entry : firstResults.asList()) {
try {
DiscoveryNode node = nodes.get(entry.value.shardTarget().nodeId());
sendReleaseSearchContext(entry.value.id(), node);
} catch (Throwable t1) {
logger.trace("failed to release context", t1);
}
}
listener.onFailure(t);
}
/**
* Releases shard targets that are not used in the docsIdsToLoad.
*/
protected void releaseIrrelevantSearchContexts(AtomicArray<? extends QuerySearchResultProvider> queryResults,
AtomicArray<IntArrayList> docIdsToLoad) {
if (docIdsToLoad == null) {
return;
}
// we only release search context that we did not fetch from if we are not scrolling
if (request.scroll() == null) {
for (AtomicArray.Entry<? extends QuerySearchResultProvider> entry : queryResults.asList()) {
final TopDocs topDocs = entry.value.queryResult().queryResult().topDocs();
if (topDocs != null && topDocs.scoreDocs.length > 0 // the shard had matches
&& docIdsToLoad.get(entry.index) == null) { // but none of them made it to the global top docs
try {
DiscoveryNode node = nodes.get(entry.value.queryResult().shardTarget().nodeId());
sendReleaseSearchContext(entry.value.queryResult().id(), node);
} catch (Throwable t1) {
logger.trace("failed to release context", t1);
}
}
}
}
}
protected void sendReleaseSearchContext(long contextId, DiscoveryNode node) {
if (node != null) {
searchService.sendFreeContext(node, contextId, request);
}
}
protected ShardFetchSearchRequest createFetchRequest(QuerySearchResult queryResult, AtomicArray.Entry<IntArrayList> entry, ScoreDoc[] lastEmittedDocPerShard) {
if (lastEmittedDocPerShard != null) {
ScoreDoc lastEmittedDoc = lastEmittedDocPerShard[entry.index];
return new ShardFetchSearchRequest(request, queryResult.id(), entry.value, lastEmittedDoc);
} else {
return new ShardFetchSearchRequest(request, queryResult.id(), entry.value);
}
}
protected abstract void sendExecuteFirstPhase(DiscoveryNode node, ShardSearchTransportRequest request, ActionListener<FirstResult> listener);
protected final void processFirstPhaseResult(int shardIndex, FirstResult result) {
firstResults.set(shardIndex, result);
if (logger.isTraceEnabled()) {
logger.trace("got first-phase result from {}", result != null ? result.shardTarget() : null);
}
// clean a previous error on this shard group (note, this code will be serialized on the same shardIndex value level
// so its ok concurrency wise to miss potentially the shard failures being created because of another failure
// in the #addShardFailure, because by definition, it will happen on *another* shardIndex
AtomicArray<ShardSearchFailure> shardFailures = this.shardFailures;
if (shardFailures != null) {
shardFailures.set(shardIndex, null);
}
}
final void innerMoveToSecondPhase() throws Exception {
if (logger.isTraceEnabled()) {
StringBuilder sb = new StringBuilder();
boolean hadOne = false;
for (int i = 0; i < firstResults.length(); i++) {
FirstResult result = firstResults.get(i);
if (result == null) {
continue; // failure
}
if (hadOne) {
sb.append(",");
} else {
hadOne = true;
}
sb.append(result.shardTarget());
}
logger.trace("Moving to second phase, based on results from: {} (cluster state version: {})", sb, clusterState.version());
}
moveToSecondPhase();
}
protected abstract void moveToSecondPhase() throws Exception;
protected abstract String firstPhaseName();
}