Queryable State Python

[Martin Eden <ma...@gmail.com>]

Hi,

Our team is looking at replacing Redis with Flink's own queryable state
mechanism. However our clients are using python.

1. Is there a python integration with the Flink queryable state mechanism?
Cannot seem to be able to find one.

2. If not, is it on the roadmap?

3. Our current solution is to write a Java RPC proxy and query that from
python. The whole point of using queryable state was to get rid of an extra
service (Redis) but now it seems we need to add another one. Is there an
easier way to call queryable state from Python without requiring an extra
service?

4. Is queryable state used in production by anyone? Can anyone share
numbers, experiences, case studies?

5. What is the direction that queryable state is going in for the next
Flink release? Features, api?

6. Is the Flink queryable state going to be supported/developed going
forward with the advent of Pravega which has caching like capabilities as
well?

Thanks,
M

Re: Queryable State Python

[Kostas Kloudas <k....@data-artisans.com>]

Hi Martin,

I will try to reply to your questions inline:

> On Nov 10, 2017, at 1:59 PM, Martin Eden <ma...@gmail.com> wrote:
> 
> Hi,
> 
> Our team is looking at replacing Redis with Flink's own queryable state mechanism. However our clients are using python.
> 
> 1. Is there a python integration with the Flink queryable state mechanism?
> Cannot seem to be able to find one.

There is no Python API for queryable state. Currently only Java is supported.

> 2. If not, is it on the roadmap?

I am not aware of any efforts towards that direction, although there are discussions about porting queryable state to REST, so 
that more clients (in any language) can be written.
> 
> 3. Our current solution is to write a Java RPC proxy and query that from python. The whole point of using queryable state was to get rid of an extra service (Redis) but now it seems we need to add another one. Is there an easier way to call queryable state from Python without requiring an extra service?

Unfortunately for now I am not aware of any easier way to do so.

> 
> 4. Is queryable state used in production by anyone? Can anyone share numbers, experiences, case studies?

Queryable state is currently under heavy development. So APIs may change and features may be added. 
For queryable state users, I would recommend checking out the talks in previous Flink Forward editions. They are all on-line. 

> 
> 5. What is the direction that queryable state is going in for the next Flink release? Features, api?

The next release is going to come soon (it is currently under testing), so you can already have a look on how Queryable State
is going to look like if you check out the current release-1.4 branch of Flink on GitHub.

> 
> 6. Is the Flink queryable state going to be supported/developed going forward with the advent of Pravega which has caching like capabilities as well?

For this I am cc’ing Stephan. Probably he is more informed.

Hope this helps,
Kostas

> Thanks,
> M