Session represents a user’s connection to Parrot. It is exposed to the Parrot frontend API and is manually created and deleted by the user.
Overall, managing Sessions is quite similar to managing the Engines, with the following key similarities:
- Both of them are created explicitly.
- Both of them have an expiration mechanism.
There is still a little difference between Session's expiration mechanism and Engines. The latter one is based on the heartbeat, while Session updates their last seen time by each API call in this session. Everytime the ServeCore receives a request with its session_id, the core resets the session's expiration time.
A Session has its own ComputeGraph, GraphExecutor. And when the Session is freed, the Semantic Variables and Contexts belonging to the session's namespace are accordingly freed. For the concept of "namespace", see Semantic Variable Management.