在flink（scala）中使用kryo在某种类型上注册protobuf序列化程序时出现问题

Question

I have a code snippet as follows:

env.getConfig.registerTypeWithKryoSerializer(classOf[EventMeta], classOf[ProtobufSerializer[EventMeta]])

where EventMeta is a case class generated from proto message by scalaPB. We use flink 1.10.1 and scala 2.11.

I tried to translate the Java code from the doc: env.getConfig.registerTypeWithKryoSerializer(EventMeta.class, ProtobufSerializer.class) , but the compiler keeps telling me:

 overloaded method value registerTypeWithKryoSerializer with alternatives:
[error]   (x$1: Class[_],x$2: Class[_ <: com.esotericsoftware.kryo.Serializer[_]])Unit <and>
[error]   [T <: com.esotericsoftware.kryo.Serializer[_] with java.io.Serializable](x$1: Class[_], x$2: T)Unit
[error]  cannot be applied to (Class[com.here.lanes.laneroadreference.derivation.statefun.state.EventMeta.EventMeta], Class[org.apache.flink.statefun.flink.common.protobuf.ProtobufSerializer[com.here.lanes.laneroadreference.derivation.statefun.state.EventMeta.EventMeta]])
[error]     env.getConfig.registerTypeWithKryoSerializer(classOf[EventMeta], classOf[ProtobufSerializer[EventMeta]])

Apparently, ProtobufSerializer doesn't extend Serializer in our version of flink. Is there an error in doc or ProtobufSerializer ? How do I fix this?

Answer 1

Are you importing this:

import com.twitter.chill.protobuf.ProtobufSerializer;