/*
* Copyright 2015-2016 MongoDB, Inc.
*
* Licensed 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 com.mongodb.async.client;
import com.mongodb.Block;
import com.mongodb.Function;
import com.mongodb.MongoNamespace;
import com.mongodb.ReadConcern;
import com.mongodb.ReadPreference;
import com.mongodb.WriteConcern;
import com.mongodb.async.AsyncBatchCursor;
import com.mongodb.async.SingleResultCallback;
import com.mongodb.client.model.Collation;
import com.mongodb.client.model.FindOptions;
import com.mongodb.operation.AggregateOperation;
import com.mongodb.operation.AggregateToCollectionOperation;
import com.mongodb.operation.AsyncOperationExecutor;
import org.bson.BsonDocument;
import org.bson.BsonValue;
import org.bson.codecs.configuration.CodecRegistry;
import org.bson.conversions.Bson;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.concurrent.TimeUnit;
import static com.mongodb.ReadPreference.primary;
import static com.mongodb.assertions.Assertions.notNull;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
class AggregateIterableImpl<TDocument, TResult> implements AggregateIterable<TResult> {
private final MongoNamespace namespace;
private final Class<TDocument> documentClass;
private final Class<TResult> resultClass;
private final ReadPreference readPreference;
private final ReadConcern readConcern;
private final WriteConcern writeConcern;
private final CodecRegistry codecRegistry;
private final AsyncOperationExecutor executor;
private final List<? extends Bson> pipeline;
private Boolean allowDiskUse;
private Integer batchSize;
private long maxTimeMS;
private Boolean useCursor;
private Boolean bypassDocumentValidation;
private Collation collation;
AggregateIterableImpl(final MongoNamespace namespace, final Class<TDocument> documentClass, final Class<TResult> resultClass,
final CodecRegistry codecRegistry, final ReadPreference readPreference, final ReadConcern readConcern,
final WriteConcern writeConcern, final AsyncOperationExecutor executor, final List<? extends Bson> pipeline) {
this.namespace = notNull("namespace", namespace);
this.documentClass = notNull("documentClass", documentClass);
this.resultClass = notNull("resultClass", resultClass);
this.codecRegistry = notNull("codecRegistry", codecRegistry);
this.readPreference = notNull("readPreference", readPreference);
this.readConcern = notNull("readConcern", readConcern);
this.writeConcern = notNull("writeConcern", writeConcern);
this.executor = notNull("executor", executor);
this.pipeline = notNull("pipeline", pipeline);
}
@Override
public AggregateIterable<TResult> allowDiskUse(final Boolean allowDiskUse) {
this.allowDiskUse = allowDiskUse;
return this;
}
@Override
public AggregateIterable<TResult> batchSize(final int batchSize) {
this.batchSize = batchSize;
return this;
}
@Override
public AggregateIterable<TResult> maxTime(final long maxTime, final TimeUnit timeUnit) {
notNull("timeUnit", timeUnit);
this.maxTimeMS = TimeUnit.MILLISECONDS.convert(maxTime, timeUnit);
return this;
}
@Override
@Deprecated
public AggregateIterable<TResult> useCursor(final Boolean useCursor) {
this.useCursor = useCursor;
return this;
}
@Override
public void toCollection(final SingleResultCallback<Void> callback) {
List<BsonDocument> aggregateList = createBsonDocumentList();
BsonValue outCollection = getAggregateOutCollection(aggregateList);
if (outCollection == null) {
throw new IllegalStateException("The last stage of the aggregation pipeline must be $out");
}
executor.execute(new AggregateToCollectionOperation(namespace, aggregateList, writeConcern)
.maxTime(maxTimeMS, MILLISECONDS)
.allowDiskUse(allowDiskUse)
.collation(collation), callback);
}
@Override
public void first(final SingleResultCallback<TResult> callback) {
notNull("callback", callback);
execute().first(callback);
}
@Override
public void forEach(final Block<? super TResult> block, final SingleResultCallback<Void> callback) {
notNull("block", block);
notNull("callback", callback);
execute().forEach(block, callback);
}
@Override
public <A extends Collection<? super TResult>> void into(final A target, final SingleResultCallback<A> callback) {
notNull("target", target);
notNull("callback", callback);
execute().into(target, callback);
}
@Override
public <U> MongoIterable<U> map(final Function<TResult, U> mapper) {
return new MappingIterable<TResult, U>(this, mapper);
}
@Override
public void batchCursor(final SingleResultCallback<AsyncBatchCursor<TResult>> callback) {
notNull("callback", callback);
execute().batchCursor(callback);
}
@Override
public AggregateIterable<TResult> bypassDocumentValidation(final Boolean bypassDocumentValidation) {
this.bypassDocumentValidation = bypassDocumentValidation;
return this;
}
@Override
public AggregateIterable<TResult> collation(final Collation collation) {
this.collation = collation;
return this;
}
@SuppressWarnings("deprecation")
private MongoIterable<TResult> execute() {
List<BsonDocument> aggregateList = createBsonDocumentList();
BsonValue outCollection = getAggregateOutCollection(aggregateList);
if (outCollection != null) {
AggregateToCollectionOperation operation = new AggregateToCollectionOperation(namespace, aggregateList, writeConcern)
.maxTime(maxTimeMS, MILLISECONDS)
.allowDiskUse(allowDiskUse)
.bypassDocumentValidation(bypassDocumentValidation)
.collation(collation);
MongoIterable<TResult> delegated = new FindIterableImpl<TDocument, TResult>(new MongoNamespace(namespace.getDatabaseName(),
outCollection.asString().getValue()), documentClass, resultClass, codecRegistry, primary(), readConcern,
executor, new BsonDocument(), new FindOptions().collation(collation));
if (batchSize != null) {
delegated.batchSize(batchSize);
}
return new AwaitingWriteOperationIterable<TResult, Void>(operation, executor, delegated);
} else {
return new OperationIterable<TResult>(new AggregateOperation<TResult>(namespace, aggregateList, codecRegistry.get(resultClass))
.maxTime(maxTimeMS, MILLISECONDS)
.allowDiskUse(allowDiskUse)
.batchSize(batchSize)
.useCursor(useCursor)
.readConcern(readConcern)
.collation(collation),
readPreference,
executor);
}
}
private BsonValue getAggregateOutCollection(final List<BsonDocument> aggregateList) {
return aggregateList.size() == 0 ? null : aggregateList.get(aggregateList.size() - 1).get("$out");
}
private List<BsonDocument> createBsonDocumentList() {
List<BsonDocument> aggregateList = new ArrayList<BsonDocument>(pipeline.size());
for (Bson document : pipeline) {
if (document == null) {
throw new IllegalArgumentException("pipeline can not contain a null value");
}
aggregateList.add(document.toBsonDocument(documentClass, codecRegistry));
}
return aggregateList;
}
}