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https://issues.apache.org/jira/browse/FLINK-3231?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15348280#comment-15348280
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ASF GitHub Bot commented on FLINK-3231:
---------------------------------------

Github user rmetzger commented on a diff in the pull request:

    https://github.com/apache/flink/pull/2131#discussion_r68399454
  
    --- Diff: 
flink-streaming-connectors/flink-connector-kinesis/src/main/java/org/apache/flink/streaming/connectors/kinesis/proxy/KinesisProxy.java
 ---
    @@ -122,29 +173,36 @@ public GetRecordsResult getRecords(String 
shardIterator, int maxRecordsToGet) {
        }
     
        /**
    -    * Get the list of shards associated with multiple Kinesis streams
    +    * Get the complete shard list of multiple Kinesis streams.
         *
    -    * @param streamNames the list of Kinesis streams
    -    * @return a list of {@link KinesisStreamShard}s
    +    * @param streamNames Kinesis streams to retrieve the shard list for
    +    * @return shard list result
         */
    -   public List<KinesisStreamShard> getShardList(List<String> streamNames) {
    -           List<KinesisStreamShard> shardList = new ArrayList<>();
    +   public GetShardListResult getShardList(List<String> streamNames) throws 
InterruptedException {
    --- End diff --
    
    Missing `@Override` annotation


> Handle Kinesis-side resharding in Kinesis streaming consumer
> ------------------------------------------------------------
>
>                 Key: FLINK-3231
>                 URL: https://issues.apache.org/jira/browse/FLINK-3231
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Kinesis Connector, Streaming Connectors
>    Affects Versions: 1.1.0
>            Reporter: Tzu-Li (Gordon) Tai
>            Assignee: Tzu-Li (Gordon) Tai
>             Fix For: 1.1.0
>
>
> A big difference between Kinesis shards and Kafka partitions is that Kinesis 
> users can choose to "merge" and "split" shards at any time for adjustable 
> stream throughput capacity. This article explains this quite clearly: 
> https://brandur.org/kinesis-by-example.
> This will break the static shard-to-task mapping implemented in the basic 
> version of the Kinesis consumer 
> (https://issues.apache.org/jira/browse/FLINK-3229). The static shard-to-task 
> mapping is done in a simple round-robin-like distribution which can be 
> locally determined at each Flink consumer task (Flink Kafka consumer does 
> this too).
> To handle Kinesis resharding, we will need some way to let the Flink consumer 
> tasks coordinate which shards they are currently handling, and allow the 
> tasks to ask the coordinator for a shards reassignment when the task finds 
> out it has found a closed shard at runtime (shards will be closed by Kinesis 
> when it is merged and split).
> We need a centralized coordinator state store which is visible to all Flink 
> consumer tasks. Tasks can use this state store to locally determine what 
> shards it can be reassigned. Amazon KCL uses a DynamoDB table for the 
> coordination, but as described in 
> https://issues.apache.org/jira/browse/FLINK-3211, we unfortunately can't use 
> KCL for the implementation of the consumer if we want to leverage Flink's 
> checkpointing mechanics. For our own implementation, Zookeeper can be used 
> for this state store, but that means it would require the user to set up ZK 
> to work.
> Since this feature introduces extensive work, it is opened as a separate 
> sub-task from the basic implementation 
> https://issues.apache.org/jira/browse/FLINK-3229.



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