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README.md

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 # user-presence-service
 
-Part of chat-application microservices: Enables real time user-presence functionality which marks user active/inactive or online/offline based on last user activity received from the client timestamp (here: mouse-up mouse-down movements) and comparing it with a threshold time quantum.
+Part of chat-application microservices: Enables real time user-presence functionality which marks user active/inactive or online/offline using HEARTBEAT mechanism based on last user activity received from the client timestamp (here: mouse-up mouse-down movements) and comparing it with a threshold time quantum.
 
 - Worker running infinitely, checking for user's last timestamp and if found more than the threshold time quantum (~10 mins) mark them as inactive in the user-presence database (here: postgres)
+- Utilizes heartbeat mechinism to query for user status using pooling
 - utilized redis cluster to store the last active timestamp; evicition pollicy: LRU and cache size: 100mb
 - has enpoints for:
   - updating user's last active timestmap in the redis cluster