investigate pub-sub libraries

[r2rstep]

Expectations:

• splitting events delivery into publishing and dispatching
• support both for synchronous and asynchronous methods
• does not impose any architecture/code design but on the contrary should be easy to fit in any architecture
• supports in-memory bus
• supports commands and queries

Nice to have:

• support for a middleware
• automatic handlers registration (but should support manual registration)
• can fit not-in-memory buses

[r2rstep]

1. https://akhundmurad.github.io/diator/
   • imposes specific design
   • does not support in-memory bus (officially)
2. https://github.com/mcfletch/pydispatcher
   • very minimal
   • does not support splitting events delivery into publishing and dispatching
3. https://github.com/jfhbrook/pyee
   • minimialistic
   • does not support splitting events delivery into publishing and dispatching
4. https://github.com/iunary/aioemit
   • created only recently, not stable
   • very minimal right now
   • does not support splitting events delivery into publishing and dispatching
5. https://github.com/ReactiveX/RxPY
   • not intended as event or command bus library but seems to meet the requirements
   • because of the above it introduces some abundant code
   • it's only possible to subscribe to some initialized objects? So when using as event bus an event would need to be published, then subscriptions configured and then dispatched. That means it doesn't really offload developer from additional work
6. https://github.com/erdewit/eventkit
   • confusing interface
   • early stage of development of the lib

[r2rstep]

no available, up to date library provides required functionalities