org.apache.flink.api.connector.sink2

Interface SupportsWriterState<InputT,WriterStateT>

Type Parameters:

InputT - The type of the sink's input

WriterStateT - The type of the sink writer's state

All Known Subinterfaces:

StatefulSink<InputT,WriterStateT>

All Known Implementing Classes:

AsyncSinkBase, FileSink

@Public
public interface SupportsWriterState<InputT,WriterStateT>

A mixin interface for a Sink which supports a stateful StatefulSinkWriter.

The Sink needs to be serializable. All configuration should be validated eagerly. The respective sink writers are transient and will only be created in the subtasks on the taskmanagers.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	SupportsWriterState.WithCompatibleState A mix-in for SupportsWriterState that allows users to migrate from a sink with a compatible state to this sink.

Method Summary

Modifier and Type	Method and Description
SimpleVersionedSerializer<WriterStateT>	getWriterStateSerializer() Any stateful sink needs to provide this state serializer and implement StatefulSinkWriter.snapshotState(long) properly.
StatefulSinkWriter<InputT,WriterStateT>	restoreWriter(WriterInitContext context, Collection<WriterStateT> recoveredState) Create a StatefulSinkWriter from a recovered state.

Method Detail

restoreWriter

StatefulSinkWriter<InputT,WriterStateT> restoreWriter(WriterInitContext context,
                                                      Collection<WriterStateT> recoveredState)
                                               throws IOException

Create a StatefulSinkWriter from a recovered state.

Parameters:

context - the runtime context.

recoveredState - the state to recover from.

Returns:

A sink writer.

Throws:

IOException - for any failure during creation.

getWriterStateSerializer

SimpleVersionedSerializer<WriterStateT> getWriterStateSerializer()

Any stateful sink needs to provide this state serializer and implement StatefulSinkWriter.snapshotState(long) properly. The respective state is used in restoreWriter(WriterInitContext, Collection) on recovery.

Returns:

the serializer of the writer's state type.