Package org.apache.flink.runtime.asyncprocessing.operators

Class AbstractAsyncStateStreamOperatorV2<OUT>

    • Constructor Detail

      • AbstractAsyncStateStreamOperatorV2

        public AbstractAsyncStateStreamOperatorV2​(StreamOperatorParameters<OUT> parameters,
                                          int numberOfInputs)

    • Method Detail

      • newKeySelected

        public void newKeySelected​(Object newKey)
        A hook that will be invoked after a new key is selected. It is not recommended to perform async state here. Only some synchronous logic is suggested.
        Parameters:
        newKey - the new key selected.

      • getRecordProcessor

        public final <T> org.apache.flink.util.function.ThrowingConsumer<StreamRecord<T>,​Exception> getRecordProcessor​(int inputId)
        Description copied from interface: AsyncKeyOrderedProcessing
        Get the record processor that could process record from input, which is the only entry for async processing.
        Specified by:
        getRecordProcessor in interface AsyncKeyOrderedProcessing
        Parameters:
        inputId - the input identifier, start from 1. Borrow the design from org.apache.flink.streaming.api.operators.AbstractInput#inputId. This is only relevant if there is multiple inputs for the instance.

      • processNonRecord

        protected void processNonRecord​(@Nullable
                                org.apache.flink.util.function.ThrowingRunnable<? extends Exception> triggerAction,
                                @Nullable
                                org.apache.flink.util.function.ThrowingRunnable<? extends Exception> finalAction)
        Process a non-record event. This method is used to process events that are not related to records, such as watermarks or latency markers. It is used to ensure that the async state processing is performed in the correct order. Subclasses could override this method to inject some async state processing logic.
        Parameters:
        triggerAction - the action that will be performed when the event is triggered.
        finalAction - the action that will be performed when the event is finished considering the epoch control.

      • getOrCreateKeyedState

        protected <N,​S extends org.apache.flink.api.common.state.v2.State,​T> S getOrCreateKeyedState​(@Nonnull
                                                                                                         N defaultNamespace,
                                                                                                         @Nonnull
                                                                                                         org.apache.flink.api.common.typeutils.TypeSerializer<N> namespaceSerializer,
                                                                                                         @Nonnull
                                                                                                         org.apache.flink.api.common.state.v2.StateDescriptor<T> stateDescriptor)
                                                                                                  throws Exception
        Create new state (v2) based on new state descriptor.
        Throws:
        Exception

      • prepareSnapshotPreBarrier

        public void prepareSnapshotPreBarrier​(long checkpointId)
                               throws Exception
        Description copied from interface: StreamOperator
        This method is called when the operator should do a snapshot, before it emits its own checkpoint barrier.

        This method is intended not for any actual state persistence, but only for emitting some data before emitting the checkpoint barrier. Operators that maintain some small transient state that is inefficient to checkpoint (especially when it would need to be checkpointed in a re-scalable way) but can simply be sent downstream before the checkpoint. An example are opportunistic pre-aggregation operators, which have small the pre-aggregation state that is frequently flushed downstream.

        Important: This method should not be used for any actual state snapshot logic, because it will inherently be within the synchronous part of the operator's checkpoint. If heavy work is done within this method, it will affect latency and downstream checkpoint alignments.

        Specified by:
        prepareSnapshotPreBarrier in interface StreamOperator<OUT>
        Overrides:
        prepareSnapshotPreBarrier in class AbstractStreamOperatorV2<OUT>
        Parameters:
        checkpointId - The ID of the checkpoint.
        Throws:
        Exception - Throwing an exception here causes the operator to fail and go into recovery.

      • getInternalTimerService

        public <K,​N> InternalTimerService<N> getInternalTimerService​(String name,
                                                                   org.apache.flink.api.common.typeutils.TypeSerializer<N> namespaceSerializer,
                                                                   Triggerable<K,​N> triggerable)
        Description copied from class: AbstractStreamOperatorV2
        Returns a InternalTimerService that can be used to query current processing time and event time and to set timers. An operator can have several timer services, where each has its own namespace serializer. Timer services are differentiated by the string key that is given when requesting them, if you call this method with the same key multiple times you will get the same timer service instance in subsequent requests.

        Timers are always scoped to a key, the currently active key of a keyed stream operation. When a timer fires, this key will also be set as the currently active key.

        Each timer has attached metadata, the namespace. Different timer services can have a different namespace type. If you don't need namespace differentiation you can use VoidNamespaceSerializer as the namespace serializer.

        Overrides:
        getInternalTimerService in class AbstractStreamOperatorV2<OUT>
        N - The type of the timer namespace.
        Parameters:
        name - The name of the requested timer service. If no service exists under the given name a new one will be created and returned.
        namespaceSerializer - TypeSerializer for the timer namespace.
        triggerable - The Triggerable that should be invoked when timers fire

      • preProcessWatermark

        public Watermark preProcessWatermark​(Watermark watermark)
                              throws Exception
        A hook that will be triggered when receiving a watermark. Some async state can safely go within this method. Return the watermark that should be normally processed.
        Parameters:
        watermark - the receiving watermark.
        Returns:
        the watermark that should be processed. Null if there is no need for following processing.
        Throws:
        Exception

      • postProcessWatermark

        public void postProcessWatermark​(Watermark watermark)
                          throws Exception
        A hook that will be invoked after finishing advancing the watermark. It is not recommended to perform async state here. Only some synchronous logic is suggested.
        Parameters:
        watermark - the advanced watermark.
        Throws:
        Exception

      • getCurrentProcessingContext

        @VisibleForTesting
public RecordContext getCurrentProcessingContext()

      • finish

        public void finish()
            throws Exception
        Description copied from interface: StreamOperator
        This method is called at the end of data processing.

        The method is expected to flush all remaining buffered data. Exceptions during this flushing of buffered data should be propagated, in order to cause the operation to be recognized as failed, because the last data items are not processed properly.

        After this method is called, no more records can be produced for the downstream operators.

        WARNING: It is not safe to use this method to commit any transactions or other side effects! You can use this method to flush any buffered data that can later on be committed e.g. in a CheckpointListener.notifyCheckpointComplete(long).

        NOTE:This method does not need to close any resources. You should release external resources in the StreamOperator.close() method.

        Specified by:
        finish in interface StreamOperator<OUT>
        Overrides:
        finish in class AbstractStreamOperatorV2<OUT>
        Throws:
        Exception - An exception in this method causes the operator to fail.

      • close

        public void close()
           throws Exception
        Description copied from interface: StreamOperator
        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.

        This method is expected to make a thorough effort to release all resources that the operator has acquired.

        NOTE:It can not emit any records! If you need to emit records at the end of processing, do so in the StreamOperator.finish() method.

        Specified by:
        close in interface StreamOperator<OUT>
        Overrides:
        close in class AbstractStreamOperatorV2<OUT>
        Throws:
        Exception