[
https://issues.apache.org/jira/browse/FLINK-5991?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15928011#comment-15928011
]
ASF GitHub Bot commented on FLINK-5991:
---------------------------------------
Github user StephanEwen commented on the issue:
https://github.com/apache/flink/pull/3508
Looks good in general. Some thoughts on refinement:
- I think we should not really encourage the use of Java Serialization,
so I would suggest to remove the serializable shortcut for broadcast state. We
have it for the default operator state only as a bridge to mimick the previous
behavior (easier migration)
- Since broadcast state already defines its redistribution pattern
(broadcast), the shape of the datastructure is orthogonal. We can for example
also have broadcast map state, broadcast value state, etc. Hence, I would
suggest to take "list" somewhere into the name of the methods.
> Expose Broadcast Operator State through public APIs
> ---------------------------------------------------
>
> Key: FLINK-5991
> URL: https://issues.apache.org/jira/browse/FLINK-5991
> Project: Flink
> Issue Type: New Feature
> Components: DataStream API, State Backends, Checkpointing
> Reporter: Tzu-Li (Gordon) Tai
> Assignee: Tzu-Li (Gordon) Tai
> Fix For: 1.3.0
>
>
> The broadcast operator state functionality was added in FLINK-5265, it just
> hasn't been exposed through any public APIs yet.
> Currently, we have 2 streaming connector features for 1.3 that are pending on
> broadcast state: rescalable Kinesis / Kafka consumers with shard / partition
> discovery (FLINK-4821 & FLINK-4022). We should consider exposing broadcast
> state for the 1.3 release also.
> This JIRA also serves the purpose to discuss how we want to expose it.
> To initiate the discussion, I propose:
> 1. For the more powerful {{CheckpointedFunction}}, add the following to the
> {{OperatorStateStore}} interface:
> {code}
> <S> ListState<S> getBroadcastOperatorState(ListStateDescriptor<S>
> stateDescriptor);
> <T extends Serializable> ListState<T>
> getBroadcastSerializableListState(String stateName);
> {code}
> 2. For a simpler {{ListCheckpointed}} variant, we probably should have a
> separate {{BroadcastListCheckpointed}} interface.
> Extending {{ListCheckpointed}} to let the user define either the list state
> type of either {{PARTITIONABLE}} or {{BROADCAST}} might also be possible, if
> we can rely on a contract that the value doesn't change. Or we expose a
> defining method (e.g. {{getListStateType()}}) that is called only once in the
> operator. This would break user code, but can be considered because it is
> marked as {{PublicEvolving}}.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
