com.mongodb.spark.rdd.partitioner.DefaultMongoPartitioner.scala Maven / Gradle / Ivy
/*
* Copyright 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.spark.rdd.partitioner
import org.bson.BsonDocument
import com.mongodb.spark.MongoConnector
import com.mongodb.spark.config.ReadConfig
/**
* The default collection partitioner implementation
*
* Wraps the [[MongoSamplePartitioner]] and provides in-depth information for users of older MongoDBs.
*
* @since 1.0
*/
class DefaultMongoPartitioner extends MongoPartitioner {
override def partitions(connector: MongoConnector, readConfig: ReadConfig, pipeline: Array[BsonDocument]): Array[MongoPartition] = {
connector.hasSampleAggregateOperator(readConfig) match {
case true => MongoSamplePartitioner.partitions(connector, readConfig, pipeline)
case false =>
logError(
"""
|----------------------------------------
|WARNING: MongoDB version < 3.2 detected.
|----------------------------------------
|
|With legacy MongoDB installations you will need to explicitly configure the Spark Connector with a partitioner.
|
|This can be done by:
| * Setting a "spark.mongodb.input.partitioner" in SparkConf.
| * Setting in the "partitioner" parameter in ReadConfig.
| * Passing the "partitioner" option to the DataFrameReader.
|
|The following Partitioners are available:
|
| * MongoShardedPartitioner - for sharded clusters, requires read access to the config database.
| * MongoSplitVectorPartitioner - for single nodes or replicaSets. Utilises the SplitVector command on the primary.
| * MongoPaginateByCountPartitioner - creates a specific number of partitions. Slow as requires a query for every partition.
| * MongoPaginateBySizePartitioner - creates partitions based on data size. Slow as requires a query for every partition.
|
""".stripMargin
)
throw new UnsupportedOperationException("The DefaultMongoPartitioner requires MongoDB >= 3.2")
}
}
}
case object DefaultMongoPartitioner extends DefaultMongoPartitioner