org.apache.spark.sql.kafka010.JsonUtils.scala Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.spark.sql.kafka010
import scala.collection.mutable.HashMap
import scala.util.control.NonFatal
import org.apache.kafka.common.TopicPartition
import org.json4s.NoTypeHints
import org.json4s.jackson.Serialization
/**
* Utilities for converting Kafka related objects to and from json.
*/
private object JsonUtils {
private implicit val formats = Serialization.formats(NoTypeHints)
/**
* Read TopicPartitions from json string
*/
def partitions(str: String): Array[TopicPartition] = {
try {
Serialization.read[Map[String, Seq[Int]]](str).flatMap { case (topic, parts) =>
parts.map { part =>
new TopicPartition(topic, part)
}
}.toArray
} catch {
case NonFatal(x) =>
throw new IllegalArgumentException(
s"""Expected e.g. {"topicA":[0,1],"topicB":[0,1]}, got $str""")
}
}
/**
* Write TopicPartitions as json string
*/
def partitions(partitions: Iterable[TopicPartition]): String = {
val result = new HashMap[String, List[Int]]
partitions.foreach { tp =>
val parts: List[Int] = result.getOrElse(tp.topic, Nil)
result += tp.topic -> (tp.partition::parts)
}
Serialization.write(result)
}
/**
* Read per-TopicPartition offsets from json string
*/
def partitionOffsets(str: String): Map[TopicPartition, Long] = {
try {
Serialization.read[Map[String, Map[Int, Long]]](str).flatMap { case (topic, partOffsets) =>
partOffsets.map { case (part, offset) =>
new TopicPartition(topic, part) -> offset
}
}.toMap
} catch {
case NonFatal(x) =>
throw new IllegalArgumentException(
s"""Expected e.g. {"topicA":{"0":23,"1":-1},"topicB":{"0":-2}}, got $str""")
}
}
/**
* Write per-TopicPartition offsets as json string
*/
def partitionOffsets(partitionOffsets: Map[TopicPartition, Long]): String = {
val result = new HashMap[String, HashMap[Int, Long]]()
implicit val ordering = new Ordering[TopicPartition] {
override def compare(x: TopicPartition, y: TopicPartition): Int = {
Ordering.Tuple2[String, Int].compare((x.topic, x.partition), (y.topic, y.partition))
}
}
val partitions = partitionOffsets.keySet.toSeq.sorted // sort for more determinism
partitions.foreach { tp =>
val off = partitionOffsets(tp)
val parts = result.getOrElse(tp.topic, new HashMap[Int, Long])
parts += tp.partition -> off
result += tp.topic -> parts
}
Serialization.write(result)
}
}