Greetings!
I need to make a user-to-user chat within my application.
basic functionality - sending messages, sending pictures.
I’ve seen various samples using the socket.io or firebase. Prefer to use firebase, as i already use it in my app for social authentication. But don’t really know what exactly to use it for 
in the open source samples i’ve seen it’s simply used for DB func.
However, generally this app is a part of bigger product - we have own back-end on Spring / Django.
I didn’t find a clear algorithmic / structural description of what do i need to make a proper user-to-user chat.
The question is - what are the steps to make the user-to-user chat? what tools to use for listening for new messages on client/server side? do i have to use socket.io?
For now my understanding of ‘parts’ is:
- messages are stored in my DB. simply in one table, with the schema like (from, to, message, image, timestamp)
- chat page - showing an interface, listening to new messages(how?) , sending messages.
- firebase push notifications in send message events.
looks pretty simple, but i just want to confirm that this is the right understanding 