[jira] [Commented] (FLINK-7552) Extend SinkFunction interface with SinkContext

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-7552?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16145339#comment-16145339 ] 

ASF GitHub Bot commented on FLINK-7552:
---------------------------------------

GitHub user aljoscha opened a pull request:

    https://github.com/apache/flink/pull/4616

    [FLINK-7552] [FLINK-7553] Enhance SinkInterface / Use in FlinkKafkaProducer

    ## What is the purpose of the change
    
    Enhance `SinkFunction` with a way of retrieving the element timestamp. This allows us to get rid of the hybrid nature of `FlinkKafkaProducer010`.
    
    This is keeping the legacy static "convenience" methods à la `FlinkKafkaProducer010.writeToKafkaWithTimestamps` for backwards compatibility.
    
    ## Brief change log
    
      - Enhance Sink interface
      - Use new interface in Kafka Producer
    
    ## Verifying this change
    
    This change is already covered by existing tests, such as *(please describe tests)*.
    
    ## Does this pull request potentially affect one of the following parts:
    
      - Dependencies (does it add or upgrade a dependency): no
      - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: no
      - The serializers: no
      - The runtime per-record code paths (performance sensitive): yes, call stack of KafkaProducer with writing timestamps is changed slightly, also, `StreamSink` operator now has a context object.
      - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: no
    
    ## Documentation
    
      - Does this pull request introduce a new feature? no
      - If yes, how is the feature documented? not applicable


You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/aljoscha/flink jira-7553-fix-kafka010-producer

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/flink/pull/4616.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #4616
    
----
commit 0b5bea36247736a0160ce584b94050d7b676d091
Author: Aljoscha Krettek <al...@gmail.com>
Date:   2017-08-29T13:50:56Z

    [FLINK-7552] Extend SinkFunction interface with SinkContext

commit d3a7b294542ea40287290ff4970715ead621d398
Author: Aljoscha Krettek <al...@gmail.com>
Date:   2017-08-29T13:53:16Z

    [FLINK-7553] Use new SinkFunction interface in FlinkKafkaProducer010

----


> Extend SinkFunction interface with SinkContext
> ----------------------------------------------
>
>                 Key: FLINK-7552
>                 URL: https://issues.apache.org/jira/browse/FLINK-7552
>             Project: Flink
>          Issue Type: Bug
>          Components: DataStream API
>            Reporter: Aljoscha Krettek
>            Assignee: Aljoscha Krettek
>             Fix For: 1.4.0
>
>
> Now that we require Java 8 we can extend the {{SinkFunction}} interface without breaking backwards compatibility. I'm proposing this:
> {code}
> /**
>  * Interface for implementing user defined sink functionality.
>  *
>  * @param <IN> Input type parameter.
>  */
> @Public
> public interface SinkFunction<IN> extends Function, Serializable {
> 	/**
> 	 * Function for standard sink behaviour. This function is called for every record.
> 	 *
> 	 * @param value The input record.
> 	 * @throws Exception
> 	 * @deprecated Use {@link #invoke(SinkContext, Object)}.
> 	 */
> 	@Deprecated
> 	default void invoke(IN value) throws Exception {
> 	}
> 	/**
> 	 * Writes the given value to the sink. This function is called for every record.
> 	 *
> 	 * @param context Additional context about the input record.
> 	 * @param value The input record.
> 	 * @throws Exception
> 	 */
> 	default void invoke(SinkContext context, IN value) throws Exception {
> 		invoke(value);
> 	}
> 	/**
> 	 * Context that {@link SinkFunction SinkFunctions } can use for getting additional data about
> 	 * an input record.
> 	 *
> 	 * @param <T> The type of elements accepted by the sink.
> 	 */
> 	@Public // Interface might be extended in the future with additional methods.
> 	interface SinkContext<T> {
> 		/**
> 		 * Returns the timestamp of the current input record.
> 		 */
> 		long timestamp();
> 	}
> }
> {code}
> For now, this only allows access to the element timestamp. This would allow us to fix the abomination that is {{FlinkKafkaProducer010}}, which is a hybrid {{SinkFunction}}/{{StreamOperator}} only because it needs access to timestamps.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)