(a) It is by design. For keyed state, you can only access state for that
key, not others. If you want one value per key, ValueState fits more
appropriate that MapState.
(b) state-processor-api aims to access/create/modify/upgrade offline
savepoint but not running state. Queryable state may meet your requirement,
but it is not actively developed for a while according to my observation
and still beta.

Queryable state:
https://ci.apache.org/projects/flink/flink-docs-release-1.12/dev/stream/state/queryable_state.html


On February 9, 2021 at 22:09:29, Sandeep khanzode (sand...@shiftright.ai)
wrote:

Hello,

I am creating a class that extends RichCoFlatMapFunction. I need to
connect() two streams to basically share the state of one stream in
another.

This is what I do:

private transient MapState<KeyClass, ValueClass> state;

@Override

public void open(Configuration parameters) throws Exception {
    MapStateDescriptor<KeyClass, ValueClass> stateDescriptor =
            new MapStateDescriptor<>(“abc-saved-state",
                    Types.POJO(KeyClass.class), Types.POJO(ValueClass.class));
    state = getRuntimeContext().getMapState(stateDescriptor);


This works correctly.


I have two questions:
(a) Whenever I debug, I can only see the current key in the MapState, not
all the possible keys that were created before and saved. Next time, I get
a hit for another key, I will only see the other key and not the rest of
previous keys. Is it by design or am I missing something?

(b) Can I somehow access this state beyond the class that holds the state?
I.e. can I access the state in some other class? If not, can I use the
https://ci.apache.org/projects/flink/flink-docs-release-1.9/dev/libs/state_processor_api.html
to
do this? Is that the correct way to access the running state of one stream
elsewhere in the program without corrupting it?


Your response will be greatly appreciated. I will be happy to add more
details if required.

Thanks,
Sandeep Ramesh Khanzode

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