org.apache.flink.runtime.LeaderSessionMessageFilter.scala Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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* 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
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package org.apache.flink.runtime
import java.util.UUID
import org.apache.flink.runtime.messages.JobManagerMessages.LeaderSessionMessage
import org.apache.flink.runtime.messages.RequiresLeaderSessionID
/** Mixin to filter out [[LeaderSessionMessage]] which contain an invalid leader session id.
* Messages which contain a valid leader session ID are unwrapped and forwarded to the actor.
*
*/
trait LeaderSessionMessageFilter extends FlinkActor {
protected def leaderSessionID: Option[UUID]
abstract override def receive: Receive = {
case leaderMessage @ LeaderSessionMessage(msgID, msg) =>
leaderSessionID match {
case Some(leaderId) =>
if (leaderId.equals(msgID)) {
super.receive(msg)
} else {
handleDiscardedMessage(leaderId, leaderMessage)
}
case None =>
handleNoLeaderId(leaderMessage)
}
case msg: RequiresLeaderSessionID =>
throw new Exception(s"Received a message $msg without a leader session ID, even though" +
s" the message requires a leader session ID.")
case msg =>
super.receive(msg)
}
private def handleDiscardedMessage(
expectedLeaderSessionID: UUID,
msg: LeaderSessionMessage)
: Unit = {
log.warn(s"Discard message $msg because the expected leader session ID " +
s"$expectedLeaderSessionID did not equal the received leader session ID " +
s"${msg.leaderSessionID}.")
}
private def handleNoLeaderId(msg: LeaderSessionMessage): Unit = {
log.warn(s"Discard message $msg because there is currently no valid leader id known.")
}
/** Wrap [[RequiresLeaderSessionID]] messages in a [[LeaderSessionMessage]]
*
* @param message The message to decorate
* @return The decorated message
*/
override def decorateMessage(message: Any): Any = {
message match {
case msg: RequiresLeaderSessionID =>
LeaderSessionMessage(leaderSessionID.orNull, super.decorateMessage(msg))
case msg => super.decorateMessage(msg)
}
}
}