I have a very common problem and believe me I am not able to find a apt solution over the internet .

[problem]: Front end application

Here in this current architecture I have tried using

SNS

But not able to figure out do I send data to a particular logged in user from Application A

SQS

Same issue on how do I send data to a particular logged in user

push notification That works for every user but still it requires permission from browser and a lot of other stuff

I have also come up my own solution which became very complicated but this is a very common problem and there is always a very good design for this I am sure but not able to figure out what it is?

The java application is spring boot

The middle one is Nodejs

The front end is JavaScript

Can some one give me some idea on how do I achieve this ,or if someone can guide me into a correct direction is much appreciated .

Thank you.