kafka.server.BrokerMetadataCheckpoint.scala Maven / Gradle / Ivy
/**
* 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 kafka.server
import java.io._
import java.util.Properties
import kafka.utils._
import org.apache.kafka.common.utils.Utils
case class BrokerMetadata(brokerId: Int)
/**
* This class saves broker's metadata to a file
*/
class BrokerMetadataCheckpoint(val file: File) extends Logging {
private val lock = new Object()
new File(file + ".tmp").delete() // try to delete any existing temp files for cleanliness
def write(brokerMetadata: BrokerMetadata) = {
lock synchronized {
try {
val brokerMetaProps = new Properties()
brokerMetaProps.setProperty("version", 0.toString)
brokerMetaProps.setProperty("broker.id", brokerMetadata.brokerId.toString)
val temp = new File(file.getAbsolutePath + ".tmp")
val fileOutputStream = new FileOutputStream(temp)
brokerMetaProps.store(fileOutputStream,"")
fileOutputStream.flush()
fileOutputStream.getFD().sync()
fileOutputStream.close()
Utils.atomicMoveWithFallback(temp.toPath, file.toPath)
} catch {
case ie: IOException =>
error("Failed to write meta.properties due to", ie)
throw ie
}
}
}
def read(): Option[BrokerMetadata] = {
lock synchronized {
try {
val brokerMetaProps = new VerifiableProperties(Utils.loadProps(file.getAbsolutePath()))
val version = brokerMetaProps.getIntInRange("version", (0, Int.MaxValue))
version match {
case 0 =>
val brokerId = brokerMetaProps.getIntInRange("broker.id", (0, Int.MaxValue))
return Some(BrokerMetadata(brokerId))
case _ =>
throw new IOException("Unrecognized version of the server meta.properties file: " + version)
}
} catch {
case e: FileNotFoundException =>
warn("No meta.properties file under dir %s".format(file.getAbsolutePath()))
None
case e1: Exception =>
error("Failed to read meta.properties file under dir %s due to %s".format(file.getAbsolutePath(), e1.getMessage))
throw e1
}
}
}
}