Hi Alex, Thanks for your reply. The application is streaming. The issue with using messaging channels for such kind of communication is the 'race condition'. I mean, when you have parallel channels of communication (one for the main flow of your streaming application and one for bringing 'stated/current' objects to desired processing nodes), then the order of messages are not preserved and it might lead to incorrect result of your application. That was the reason why I was wondering if there is any 'synchronous' way of accessing the Flink state.
BR, Moe On 06/08/2019 13:25, Протченко Алексей wrote: Hi Mohammad, which types of applications do you mean? Streaming or batch ones? In terms of streaming ones queues like Kafka or RabbitMq between applications should be the best way I think. Best regards, Alex Вторник, 6 августа 2019, 12:21 +02:00 от Mohammad Hosseinian <mohammad.hossein...@id1.de><mailto:mohammad.hossein...@id1.de>: Hi all, We have a network of Flink applications. The whole cluster receives 'state-update' messages from the outside, and there is one Flink application in our cluster that 'merges' these updates and creates the actual, most up-to-date, state of the 'data-objects' and passes it to the next process. It does this, using a stateful stream processing with a `KeyedProcessFunction` object. In our processing logic, there are nodes that require to access the actual state of the objects when they receive one or more 'object-id's from the previous Flink application. We do not propagate the actual-state of the objects since, not all types of the objects are relevant to all processes in the cluster, so we saved some network/storage overhead there. The question is: for such scenario, what is the best way to expose the Flink state to another Flink application? I am aware of 'Queryable states', but I am not sure if this feature has been designed and is suitable for our use-case or not? Thank you very much in advance. BR, Moe -- Mohammad Hosseinian Software Developer Information Design One AG Phone +49-69-244502-0 Fax +49-69-244502-10 Web www.id1.de<http://www.id1.de> Information Design One AG, Baseler Strasse 10, 60329 Frankfurt am Main, Germany Registration: Amtsgericht Frankfurt am Main, HRB 52596 Executive Board: Robert Peters, Benjamin Walther, Supervisory Board: Christian Hecht -- Протченко Алексей -- Mohammad Hosseinian Software Developer Information Design One AG Phone +49-69-244502-0 Fax +49-69-244502-10 Web www.id1.de<http://www.id1.de> Information Design One AG, Baseler Strasse 10, 60329 Frankfurt am Main, Germany Registration: Amtsgericht Frankfurt am Main, HRB 52596 Executive Board: Robert Peters, Benjamin Walther, Supervisory Board: Christian Hecht
