com.mongodb.operation.MapReduceToCollectionOperation Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of mongo-java-driver Show documentation
Show all versions of mongo-java-driver Show documentation
The MongoDB Java Driver uber-artifact, containing the legacy driver, the mongodb-driver, mongodb-driver-core, and bson
/*
* Copyright 2008-present 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.operation;
import com.mongodb.ExplainVerbosity;
import com.mongodb.MongoNamespace;
import com.mongodb.ServerAddress;
import com.mongodb.WriteConcern;
import com.mongodb.async.SingleResultCallback;
import com.mongodb.binding.AsyncWriteBinding;
import com.mongodb.binding.WriteBinding;
import com.mongodb.client.model.Collation;
import com.mongodb.connection.AsyncConnection;
import com.mongodb.connection.Connection;
import com.mongodb.connection.ConnectionDescription;
import com.mongodb.operation.CommandOperationHelper.CommandTransformer;
import org.bson.BsonBoolean;
import org.bson.BsonDocument;
import org.bson.BsonJavaScript;
import org.bson.BsonNull;
import org.bson.BsonString;
import org.bson.BsonValue;
import org.bson.codecs.BsonDocumentCodec;
import java.util.List;
import java.util.concurrent.TimeUnit;
import static com.mongodb.assertions.Assertions.isTrue;
import static com.mongodb.assertions.Assertions.notNull;
import static com.mongodb.internal.async.ErrorHandlingResultCallback.errorHandlingCallback;
import static com.mongodb.operation.CommandOperationHelper.executeWrappedCommandProtocol;
import static com.mongodb.operation.CommandOperationHelper.executeWrappedCommandProtocolAsync;
import static com.mongodb.operation.DocumentHelper.putIfNotZero;
import static com.mongodb.operation.DocumentHelper.putIfTrue;
import static com.mongodb.operation.OperationHelper.AsyncCallableWithConnection;
import static com.mongodb.operation.OperationHelper.LOGGER;
import static com.mongodb.operation.OperationHelper.validateCollation;
import static com.mongodb.operation.OperationHelper.releasingCallback;
import static com.mongodb.internal.operation.ServerVersionHelper.serverIsAtLeastVersionThreeDotTwo;
import static com.mongodb.operation.OperationHelper.withConnection;
import static com.mongodb.internal.operation.WriteConcernHelper.appendWriteConcernToCommand;
import static com.mongodb.internal.operation.WriteConcernHelper.throwOnWriteConcernError;
import static java.util.Arrays.asList;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
/**
* Operation that runs a Map Reduce against a MongoDB instance. This operation does not support "inline" results, i.e. the results will
* be output into the collection represented by the MongoNamespace provided.
*
* To run a map reduce operation and receive the results inline (i.e. as a response to running the command) use {@code
* MapReduceToCollectionOperation}.
*
* @mongodb.driver.manual core/map-reduce Map Reduce
* @since 3.0
*/
public class
MapReduceToCollectionOperation implements AsyncWriteOperation, WriteOperation {
private final MongoNamespace namespace;
private final BsonJavaScript mapFunction;
private final BsonJavaScript reduceFunction;
private final String collectionName;
private final WriteConcern writeConcern;
private BsonJavaScript finalizeFunction;
private BsonDocument scope;
private BsonDocument filter;
private BsonDocument sort;
private int limit;
private boolean jsMode;
private boolean verbose;
private long maxTimeMS;
private String action = "replace";
private String databaseName;
private boolean sharded;
private boolean nonAtomic;
private Boolean bypassDocumentValidation;
private Collation collation;
private static final List VALID_ACTIONS = asList("replace", "merge", "reduce");
/**
* Construct a MapReduceOperation with all the criteria it needs to execute
*
* @param namespace the database and collection namespace for the operation.
* @param mapFunction a JavaScript function that associates or "maps" a value with a key and emits the key and value pair.
* @param reduceFunction a JavaScript function that "reduces" to a single object all the values associated with a particular key.
* @param collectionName the name of the collection to output the results to.
* @mongodb.driver.manual core/map-reduce Map Reduce
*/
public MapReduceToCollectionOperation(final MongoNamespace namespace, final BsonJavaScript mapFunction,
final BsonJavaScript reduceFunction, final String collectionName) {
this(namespace, mapFunction, reduceFunction, collectionName, null);
}
/**
* Construct a MapReduceOperation with all the criteria it needs to execute
*
* @param namespace the database and collection namespace for the operation.
* @param mapFunction a JavaScript function that associates or "maps" a value with a key and emits the key and value pair.
* @param reduceFunction a JavaScript function that "reduces" to a single object all the values associated with a particular key.
* @param collectionName the name of the collection to output the results to.
* @param writeConcern the write concern
* @mongodb.driver.manual core/map-reduce Map Reduce
*
* @since 3.4
*/
public MapReduceToCollectionOperation(final MongoNamespace namespace, final BsonJavaScript mapFunction,
final BsonJavaScript reduceFunction, final String collectionName,
final WriteConcern writeConcern) {
this.namespace = notNull("namespace", namespace);
this.mapFunction = notNull("mapFunction", mapFunction);
this.reduceFunction = notNull("reduceFunction", reduceFunction);
this.collectionName = notNull("collectionName", collectionName);
this.writeConcern = writeConcern;
}
/**
* Gets the namespace.
*
* @return the namespace
* @since 3.4
*/
public MongoNamespace getNamespace() {
return namespace;
}
/**
* Gets the JavaScript function that associates or "maps" a value with a key and emits the key and value pair.
*
* @return the JavaScript function that associates or "maps" a value with a key and emits the key and value pair.
*/
public BsonJavaScript getMapFunction() {
return mapFunction;
}
/**
* Gets the JavaScript function that "reduces" to a single object all the values associated with a particular key.
*
* @return the JavaScript function that "reduces" to a single object all the values associated with a particular key.
*/
public BsonJavaScript getReduceFunction() {
return reduceFunction;
}
/**
* Gets the name of the collection to output the results to.
*
* @return the name of the collection to output the results to.
*/
public String getCollectionName() {
return collectionName;
}
/**
* Gets the write concern.
*
* @return the write concern, which may be null
*
* @since 3.4
*/
public WriteConcern getWriteConcern() {
return writeConcern;
}
/**
* Gets the JavaScript function that follows the reduce method and modifies the output. Default is null
*
* @return the JavaScript function that follows the reduce method and modifies the output.
* @mongodb.driver.manual reference/command/mapReduce/#mapreduce-finalize-cmd Requirements for the finalize Function
*/
public BsonJavaScript getFinalizeFunction() {
return finalizeFunction;
}
/**
* Sets the JavaScript function that follows the reduce method and modifies the output.
*
* @param finalizeFunction the JavaScript function that follows the reduce method and modifies the output.
* @return this
* @mongodb.driver.manual reference/command/mapReduce/#mapreduce-finalize-cmd Requirements for the finalize Function
*/
public MapReduceToCollectionOperation finalizeFunction(final BsonJavaScript finalizeFunction) {
this.finalizeFunction = finalizeFunction;
return this;
}
/**
* Gets the global variables that are accessible in the map, reduce and finalize functions.
*
* @return the global variables that are accessible in the map, reduce and finalize functions.
* @mongodb.driver.manual reference/command/mapReduce Scope
*/
public BsonDocument getScope() {
return scope;
}
/**
* Sets the global variables that are accessible in the map, reduce and finalize functions.
*
* @param scope the global variables that are accessible in the map, reduce and finalize functions.
* @return this
* @mongodb.driver.manual reference/command/mapReduce mapReduce
*/
public MapReduceToCollectionOperation scope(final BsonDocument scope) {
this.scope = scope;
return this;
}
/**
* Gets the query filter.
*
* @return the query filter
* @mongodb.driver.manual reference/method/db.collection.find/ Filter
*/
public BsonDocument getFilter() {
return filter;
}
/**
* Sets the filter to apply to the query.
*
* @param filter the filter to apply to the query.
* @return this
* @mongodb.driver.manual reference/method/db.collection.find/ Filter
*/
public MapReduceToCollectionOperation filter(final BsonDocument filter) {
this.filter = filter;
return this;
}
/**
* Gets the sort criteria to apply to the query. The default is null, which means that the documents will be returned in an undefined
* order.
*
* @return a document describing the sort criteria
* @mongodb.driver.manual reference/method/cursor.sort/ Sort
*/
public BsonDocument getSort() {
return sort;
}
/**
* Sets the sort criteria to apply to the query.
*
* @param sort the sort criteria, which may be null.
* @return this
* @mongodb.driver.manual reference/method/cursor.sort/ Sort
*/
public MapReduceToCollectionOperation sort(final BsonDocument sort) {
this.sort = sort;
return this;
}
/**
* Gets the limit to apply. The default is null.
*
* @return the limit
* @mongodb.driver.manual reference/method/cursor.limit/#cursor.limit Limit
*/
public int getLimit() {
return limit;
}
/**
* Sets the limit to apply.
*
* @param limit the limit, which may be null
* @return this
* @mongodb.driver.manual reference/method/cursor.limit/#cursor.limit Limit
*/
public MapReduceToCollectionOperation limit(final int limit) {
this.limit = limit;
return this;
}
/**
* Gets the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and reduce
* functions. Defaults to false.
*
* @return jsMode
* @mongodb.driver.manual reference/command/mapReduce mapReduce
*/
public boolean isJsMode() {
return jsMode;
}
/**
* Sets the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and reduce
* functions. Defaults to false.
*
* @param jsMode the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and
* reduce functions
* @return jsMode
* @mongodb.driver.manual reference/command/mapReduce mapReduce
*/
public MapReduceToCollectionOperation jsMode(final boolean jsMode) {
this.jsMode = jsMode;
return this;
}
/**
* Gets whether to include the timing information in the result information. Defaults to true.
*
* @return whether to include the timing information in the result information
*/
public boolean isVerbose() {
return verbose;
}
/**
* Sets whether to include the timing information in the result information.
*
* @param verbose whether to include the timing information in the result information.
* @return this
*/
public MapReduceToCollectionOperation verbose(final boolean verbose) {
this.verbose = verbose;
return this;
}
/**
* Gets the maximum execution time on the server for this operation. The default is 0, which places no limit on the execution time.
*
* @param timeUnit the time unit to return the result in
* @return the maximum execution time in the given time unit
* @mongodb.driver.manual reference/method/cursor.maxTimeMS/#cursor.maxTimeMS Max Time
*/
public long getMaxTime(final TimeUnit timeUnit) {
notNull("timeUnit", timeUnit);
return timeUnit.convert(maxTimeMS, TimeUnit.MILLISECONDS);
}
/**
* Sets the maximum execution time on the server for this operation.
*
* @param maxTime the max time
* @param timeUnit the time unit, which may not be null
* @return this
* @mongodb.driver.manual reference/method/cursor.maxTimeMS/#cursor.maxTimeMS Max Time
*/
public MapReduceToCollectionOperation maxTime(final long maxTime, final TimeUnit timeUnit) {
notNull("timeUnit", timeUnit);
this.maxTimeMS = TimeUnit.MILLISECONDS.convert(maxTime, timeUnit);
return this;
}
/**
* Gets the output action, one of: "replace", "merge", "reduce". Defaults to "replace".
*
* @return the output action
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public String getAction() {
return action;
}
/**
* Sets the output action one of: "replace", "merge", "reduce"
*
* @param action the output action
* @return this
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public MapReduceToCollectionOperation action(final String action) {
notNull("action", action);
isTrue("action must be one of: \"replace\", \"merge\", \"reduce\"", VALID_ACTIONS.contains(action));
this.action = action;
return this;
}
/**
* Gets the name of the database to output into.
*
* @return the name of the database to output into.
*/
public String getDatabaseName() {
return databaseName;
}
/**
* Sets the name of the database to output into.
*
* @param databaseName the name of the database to output into.
* @return this
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public MapReduceToCollectionOperation databaseName(final String databaseName) {
this.databaseName = databaseName;
return this;
}
/**
* True if the output database is sharded
*
* @return true if the output database is sharded
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public boolean isSharded() {
return sharded;
}
/**
* Sets if the output database is sharded
*
* @param sharded if the output database is sharded
* @return this
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public MapReduceToCollectionOperation sharded(final boolean sharded) {
this.sharded = sharded;
return this;
}
/**
* True if the post-processing step will prevent MongoDB from locking the database.
*
* @return if true the post-processing step will prevent MongoDB from locking the database.
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public boolean isNonAtomic() {
return nonAtomic;
}
/**
* Sets if the post-processing step will prevent MongoDB from locking the database.
*
* Valid only with {@code "merge"} or {@code "reduce"} actions.
*
* @param nonAtomic if the post-processing step will prevent MongoDB from locking the database.
* @return this
* @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
*/
public MapReduceToCollectionOperation nonAtomic(final boolean nonAtomic) {
this.nonAtomic = nonAtomic;
return this;
}
/**
* Gets the bypass document level validation flag
*
* @return the bypass document level validation flag
* @since 3.2
* @mongodb.server.release 3.2
*/
public Boolean getBypassDocumentValidation() {
return bypassDocumentValidation;
}
/**
* Sets the bypass document level validation flag.
*
* Note: This only applies when an $out stage is specified
.
*
* @param bypassDocumentValidation If true, allows the write to opt-out of document level validation.
* @return this
* @since 3.2
* @mongodb.server.release 3.2
*/
public MapReduceToCollectionOperation bypassDocumentValidation(final Boolean bypassDocumentValidation) {
this.bypassDocumentValidation = bypassDocumentValidation;
return this;
}
/**
* Returns the collation options
*
* @return the collation options
* @since 3.4
* @mongodb.server.release 3.4
*/
public Collation getCollation() {
return collation;
}
/**
* Sets the collation options
*
* A null value represents the server default.
* @param collation the collation options to use
* @return this
* @since 3.4
* @mongodb.server.release 3.4
*/
public MapReduceToCollectionOperation collation(final Collation collation) {
this.collation = collation;
return this;
}
/**
* Executing this will return a cursor with your results in.
*
* @param binding the binding
* @return a MongoCursor that can be iterated over to find all the results of the Map Reduce operation.
*/
@Override
public MapReduceStatistics execute(final WriteBinding binding) {
return withConnection(binding, new OperationHelper.CallableWithConnection() {
@Override
public MapReduceStatistics call(final Connection connection) {
validateCollation(connection, collation);
return executeWrappedCommandProtocol(binding, namespace.getDatabaseName(), getCommand(connection.getDescription()),
connection, transformer());
}
});
}
@Override
public void executeAsync(final AsyncWriteBinding binding, final SingleResultCallback callback) {
withConnection(binding, new AsyncCallableWithConnection() {
@Override
public void call(final AsyncConnection connection, final Throwable t) {
SingleResultCallback errHandlingCallback = errorHandlingCallback(callback, LOGGER);
if (t != null) {
errHandlingCallback.onResult(null, t);
} else {
final SingleResultCallback wrappedCallback = releasingCallback(errHandlingCallback, connection);
validateCollation(connection, collation, new AsyncCallableWithConnection() {
@Override
public void call(final AsyncConnection connection, final Throwable t) {
if (t != null) {
wrappedCallback.onResult(null, t);
} else {
executeWrappedCommandProtocolAsync(binding, namespace.getDatabaseName(),
getCommand(connection.getDescription()), connection, transformer(), wrappedCallback);
}
}
});
}
}
});
}
/**
* Gets an operation whose execution explains this operation.
*
* @param explainVerbosity the explain verbosity
* @return a read operation that when executed will explain this operation
*/
public ReadOperation asExplainableOperation(final ExplainVerbosity explainVerbosity) {
return createExplainableOperation(explainVerbosity);
}
/**
* Gets an operation whose execution explains this operation.
*
* @param explainVerbosity the explain verbosity
* @return a read operation that when executed will explain this operation
*/
public AsyncReadOperation asExplainableOperationAsync(final ExplainVerbosity explainVerbosity) {
return createExplainableOperation(explainVerbosity);
}
private CommandReadOperation createExplainableOperation(final ExplainVerbosity explainVerbosity) {
return new CommandReadOperation(namespace.getDatabaseName(),
ExplainHelper.asExplainCommand(getCommand(null), explainVerbosity),
new BsonDocumentCodec());
}
private CommandTransformer transformer() {
return new CommandTransformer() {
@SuppressWarnings("unchecked")
@Override
public MapReduceStatistics apply(final BsonDocument result, final ServerAddress serverAddress) {
throwOnWriteConcernError(result, serverAddress);
return MapReduceHelper.createStatistics(result);
}
};
}
private BsonDocument getCommand(final ConnectionDescription description) {
BsonDocument outputDocument = new BsonDocument(getAction(), new BsonString(getCollectionName()));
outputDocument.append("sharded", BsonBoolean.valueOf(isSharded()));
outputDocument.append("nonAtomic", BsonBoolean.valueOf(isNonAtomic()));
if (getDatabaseName() != null) {
outputDocument.put("db", new BsonString(getDatabaseName()));
}
BsonDocument commandDocument = new BsonDocument("mapreduce", new BsonString(namespace.getCollectionName()))
.append("map", getMapFunction())
.append("reduce", getReduceFunction())
.append("out", outputDocument)
.append("query", asValueOrNull(getFilter()))
.append("sort", asValueOrNull(getSort()))
.append("finalize", asValueOrNull(getFinalizeFunction()))
.append("scope", asValueOrNull(getScope()))
.append("verbose", BsonBoolean.valueOf(isVerbose()));
putIfNotZero(commandDocument, "limit", getLimit());
putIfNotZero(commandDocument, "maxTimeMS", getMaxTime(MILLISECONDS));
putIfTrue(commandDocument, "jsMode", isJsMode());
if (bypassDocumentValidation != null && description != null && serverIsAtLeastVersionThreeDotTwo(description)) {
commandDocument.put("bypassDocumentValidation", BsonBoolean.valueOf(bypassDocumentValidation));
}
if (description != null) {
appendWriteConcernToCommand(writeConcern, commandDocument, description);
}
if (collation != null) {
commandDocument.put("collation", collation.asDocument());
}
return commandDocument;
}
private static BsonValue asValueOrNull(final BsonValue value) {
return value == null ? BsonNull.VALUE : value;
}
}