create session failed

[m20082008m]

when my client request nebula server for long time, it return error for session

fail to authenticate, error: Create session failed: Unknown error!

nebula-storaged v2.6.1
nebula-graphd v2.6.1
nebula-metad v2.6.1
nebula-graph-studio v3.1.0
nebula-http-gateway v2.1.1
nebula-go v2.6.0

metad warning logs

W0614 05:04:45.844468   107 SessionManagerProcessor.cpp:56] Session id `1655183124722335' not found
W0614 05:09:06.080336   105 SessionManagerProcessor.cpp:56] Session id `1655183384989427' not found
W0614 05:19:56.704413   108 SessionManagerProcessor.cpp:56] Session id `1655184035640282' not found
W0614 05:21:06.777271   106 SessionManagerProcessor.cpp:56] Session id `1655184105714553' not found
W0614 05:21:46.824519   105 SessionManagerProcessor.cpp:56] Session id `1655184145761765' not found
W0614 05:24:47.016147   108 SessionManagerProcessor.cpp:56] Session id `1655184325959818' not found
W0614 05:25:07.037206   105 SessionManagerProcessor.cpp:56] Session id `1655184345977612' not found
W0614 05:27:07.169456   107 SessionManagerProcessor.cpp:56] Session id `1655184466088790' not found
W0614 05:34:07.615229   107 SessionManagerProcessor.cpp:56] Session id `1655184886565665' not found
W0614 05:36:17.764503   108 SessionManagerProcessor.cpp:56] Session id `1655185016713685' not found

graphd warning logs

E0614 05:24:47.016408    16 GraphSessionManager.cpp:205] Update sessions failed: Session not existed!
E0614 05:24:47.016480    18 GraphSessionManager.cpp:229] Update sessions failed: Update sessions failed: Session not existed!
E0614 05:25:07.037410    13 GraphSessionManager.cpp:205] Update sessions failed: Session not existed!
E0614 05:25:07.037528    18 GraphSessionManager.cpp:229] Update sessions failed: Update sessions failed: Session not existed!
E0614 05:27:07.169734    15 GraphSessionManager.cpp:205] Update sessions failed: Session not existed!
E0614 05:27:07.169849    18 GraphSessionManager.cpp:229] Update sessions failed: Update sessions failed: Session not existed!
E0614 05:34:07.615523    15 GraphSessionManager.cpp:205] Update sessions failed: Session not existed!
E0614 05:34:07.615622    18 GraphSessionManager.cpp:229] Update sessions failed: Update sessions failed: Session not existed!
E0614 05:36:17.764770    15 GraphSessionManager.cpp:205] Update sessions failed: Session not existed!
E0614 05:36:17.764878    18 GraphSessionManager.cpp:229] Update sessions failed: Update sessions failed: Session not existed!

i restart my client can solve the problem,

[wey-gu]

@Aiee could you please help advise on this? Did the session expire or?

[Aiee]

@m20082008m Could you show us the code on how you use the client? It seems you create a new session for each query. The error is caused by the inconsistency session info of graph layer and meta layer.

[m20082008m]

#184
i can't share global session for every request, so now i create a new session for each request

[m20082008m]

// NewSession for db
func NewSession(cfg module.Config) (*nebula.Session, error) {
	// Create session
	session, err := GraphPool.GetSession(cfg.GraphDB.User, cfg.GraphDB.Password)
	if err != nil {
		return nil, common.GeneralDetailError("Init graph db session error",
			codes.Internal, pb.ServiceCode_GRAPHDB_SESSION_INIT)
	}
	// Prepare the query
	initSchema := "USE " + cfg.GraphDB.Database + " ; "
	// Excute a query
	if err := tryToExecute(session, initSchema, func(resp *nebula.ResultSet) error {
		if !resp.IsSucceed() {
			return fmt.Errorf("%d %s", resp.GetErrorCode(), resp.GetErrorMsg())
		}

		return nil
	}); err != nil {
		return nil, transformError(err)
	}

	return session, err
}

	session, err := model.NewSession(module.DefaultConfig)
	if err != nil {
		return common.GeneralError("init graph db session error"+err.Error(), codes.Internal)
	}
	// Release session and return connection back to connection pool
	defer session.Release()
        gql := fmt.Sprintf(`FETCH PROP ON * '%s' yield id($$)`, strings.Join(stations, "','"))
	data := make([]struct {
		VID string `json:"VertexID"`
	}, 0)
	_, err = model.QueryGQL(session, gql, &data)
	if err != nil {
		return common.GeneralError(err.Error(), codes.Internal)
	}

[HarrisChu]

if every query create a new session, there may be two same session in meta, and if one release session, the other doesn't work well.

[m20082008m]

oh, i see. how to solve the problem? such as init a session pool?

[HarrisChu]

yes, session pool could

[QingZ11]

@m20082008m hi, I have noticed that the issue you created hasn’t been updated for nearly a month, is this issue been resolved? If not resolved, can you provide some more information? If solved, can you close this issue?

Thanks a lot for your contribution anyway 😊