OUT
- The output type of the operator.@Internal public class SourceOperator<OUT,SplitT extends SourceSplit> extends AbstractStreamOperator<OUT> implements OperatorEventHandler, PushingAsyncDataInput<OUT>
PushingAsyncDataInput
for naturally compatible with one input
processing in runtime stack.
Important Note on Serialization: The SourceOperator inherits the Serializable
interface from the StreamOperator, but is in fact NOT serializable. The
operator must only be instantiates in the StreamTask from its factory.
PushingAsyncDataInput.DataOutput<T>
AvailabilityProvider.AvailabilityHelper
chainingStrategy, config, latencyStats, LOG, metrics, output, processingTimeService
AVAILABLE
Constructor and Description |
---|
SourceOperator(FunctionWithException<SourceReaderContext,SourceReader<OUT,SplitT>,Exception> readerFactory,
OperatorEventGateway operatorEventGateway,
SimpleVersionedSerializer<SplitT> splitSerializer,
WatermarkStrategy<OUT> watermarkStrategy,
ProcessingTimeService timeService,
Configuration configuration,
String localHostname,
boolean emitProgressiveWatermarks) |
Modifier and Type | Method and Description |
---|---|
void |
close()
This method is called after all records have been added to the operators via the methods
Input.processElement(StreamRecord) , or TwoInputStreamOperator.processElement1(StreamRecord) and TwoInputStreamOperator.processElement2(StreamRecord) . |
void |
dispose()
This method is called at the very end of the operator's life, both in the case of a
successful completion of the operation, and in the case of a failure and canceling.
|
InputStatus |
emitNext(PushingAsyncDataInput.DataOutput<OUT> output)
Pushes the next element to the output from current data input, and returns the input status
to indicate whether there are more available data in current input.
|
CompletableFuture<?> |
getAvailableFuture() |
SourceReader<OUT,SplitT> |
getSourceReader() |
void |
handleOperatorEvent(OperatorEvent event) |
void |
initializeState(StateInitializationContext context)
Stream operators with state which can be restored need to override this hook method.
|
void |
initReader()
Initializes the reader.
|
void |
notifyCheckpointAborted(long checkpointId)
This method is called as a notification once a distributed checkpoint has been aborted.
|
void |
notifyCheckpointComplete(long checkpointId)
Notifies the listener that the checkpoint with the given
checkpointId completed and
was committed. |
void |
open()
This method is called immediately before any elements are processed, it should contain the
operator's initialization logic, e.g.
|
void |
snapshotState(StateSnapshotContext context)
Stream operators with state, which want to participate in a snapshot need to override this
hook method.
|
getChainingStrategy, getContainingTask, getCurrentKey, getExecutionConfig, getInternalTimerService, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getTimeServiceManager, getUserCodeClassloader, initializeState, isUsingCustomRawKeyedState, prepareSnapshotPreBarrier, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processWatermark, processWatermark1, processWatermark2, reportOrForwardLatencyMarker, setChainingStrategy, setCurrentKey, setKeyContextElement1, setKeyContextElement2, setProcessingTimeService, setup, snapshotState
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
and, isApproximatelyAvailable, isAvailable, or
public SourceOperator(FunctionWithException<SourceReaderContext,SourceReader<OUT,SplitT>,Exception> readerFactory, OperatorEventGateway operatorEventGateway, SimpleVersionedSerializer<SplitT> splitSerializer, WatermarkStrategy<OUT> watermarkStrategy, ProcessingTimeService timeService, Configuration configuration, String localHostname, boolean emitProgressiveWatermarks)
public void initReader() throws Exception
Calling this method explicitly is an optional way to have the reader initialization a bit
earlier than in open(), as needed by the SourceOperatorStreamTask
This code should move to the constructor once the metric groups are available at task setup time.
Exception
public void open() throws Exception
AbstractStreamOperator
The default implementation does nothing.
open
in interface StreamOperator<OUT>
open
in class AbstractStreamOperator<OUT>
Exception
- An exception in this method causes the operator to fail.public void close() throws Exception
AbstractStreamOperator
Input.processElement(StreamRecord)
, or TwoInputStreamOperator.processElement1(StreamRecord)
and TwoInputStreamOperator.processElement2(StreamRecord)
.
The method is expected to flush all remaining buffered data. Exceptions during this flushing of buffered should be propagated, in order to cause the operation to be recognized asa failed, because the last data items are not processed properly.
close
in interface StreamOperator<OUT>
close
in class AbstractStreamOperator<OUT>
Exception
- An exception in this method causes the operator to fail.public void dispose() throws Exception
AbstractStreamOperator
This method is expected to make a thorough effort to release all resources that the operator has acquired.
dispose
in interface StreamOperator<OUT>
dispose
in interface Disposable
dispose
in class AbstractStreamOperator<OUT>
Exception
- if something goes wrong during disposal.public InputStatus emitNext(PushingAsyncDataInput.DataOutput<OUT> output) throws Exception
PushingAsyncDataInput
This method should be non blocking.
emitNext
in interface PushingAsyncDataInput<OUT>
Exception
public void snapshotState(StateSnapshotContext context) throws Exception
AbstractStreamOperator
snapshotState
in interface StreamOperatorStateHandler.CheckpointedStreamOperator
snapshotState
in class AbstractStreamOperator<OUT>
context
- context that provides information and means required for taking a snapshotException
public CompletableFuture<?> getAvailableFuture()
getAvailableFuture
in interface AvailabilityProvider
public void initializeState(StateInitializationContext context) throws Exception
AbstractStreamOperator
initializeState
in interface StreamOperatorStateHandler.CheckpointedStreamOperator
initializeState
in class AbstractStreamOperator<OUT>
context
- context that allows to register different states.Exception
public void notifyCheckpointComplete(long checkpointId) throws Exception
CheckpointListener
checkpointId
completed and
was committed.
These notifications are "best effort", meaning they can sometimes be skipped. To behave
properly, implementers need to follow the "Checkpoint Subsuming Contract". Please see the
class-level JavaDocs
for details.
Please note that checkpoints may generally overlap, so you cannot assume that the notifyCheckpointComplete()
call is always for the latest prior checkpoint (or snapshot) that
was taken on the function/operator implementing this interface. It might be for a checkpoint
that was triggered earlier. Implementing the "Checkpoint Subsuming Contract" (see above)
properly handles this situation correctly as well.
Please note that throwing exceptions from this method will not cause the completed checkpoint to be revoked. Throwing exceptions will typically cause task/job failure and trigger recovery.
notifyCheckpointComplete
in interface CheckpointListener
notifyCheckpointComplete
in class AbstractStreamOperator<OUT>
checkpointId
- The ID of the checkpoint that has been completed.Exception
- This method can propagate exceptions, which leads to a failure/recovery for
the task. Not that this will NOT lead to the checkpoint being revoked.public void notifyCheckpointAborted(long checkpointId) throws Exception
CheckpointListener
Important: The fact that a checkpoint has been aborted does NOT mean that the data
and artifacts produced between the previous checkpoint and the aborted checkpoint are to be
discarded. The expected behavior is as if this checkpoint was never triggered in the first
place, and the next successful checkpoint simply covers a longer time span. See the
"Checkpoint Subsuming Contract" in the class-level JavaDocs
for
details.
These notifications are "best effort", meaning they can sometimes be skipped.
This method is very rarely necessary to implement. The "best effort" guarantee, together with the fact that this method should not result in discarding any data (per the "Checkpoint Subsuming Contract") means it is mainly useful for earlier cleanups of auxiliary resources. One example is to pro-actively clear a local per-checkpoint state cache upon checkpoint failure.
notifyCheckpointAborted
in interface CheckpointListener
notifyCheckpointAborted
in class AbstractStreamOperator<OUT>
checkpointId
- The ID of the checkpoint that has been aborted.Exception
- This method can propagate exceptions, which leads to a failure/recovery for
the task or job.public void handleOperatorEvent(OperatorEvent event)
handleOperatorEvent
in interface OperatorEventHandler
@VisibleForTesting public SourceReader<OUT,SplitT> getSourceReader()
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