design patterns - state sharing with push & pull via redis -

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i share state via redis following requirements:

  1. decoupling: uncoupled publishers , subscribers
  2. single ownership: each state set single publisher
  3. push: once state changes relevant subscribers must notified
  4. pull: once subscriber initializes should pull relevant states

if push required without pull pub\sub optimal
if pull required without push simple redis key , value work well

what best design pattern support requirements?

one solution use both pub\sub publish (push) state changes , hash keep latest published state of each kind subscriber can read (pull)

the hurdle need handle race conditions follows:

  • publisher should notify , update state
  • subscriber should first subscribe , read state

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