(sessionId string)
| 28 | SessionExist(sessionId string) bool |
| 29 | SessionUpdate(state *SessionState) error |
| 30 | SessionRemove(sessionId string) error |
| 31 | SessionCount() int // get all active session length |
| 32 | SessionGC() int // gc session and return out of date state num |
| 33 | } |