Sessions

[mig824]

Can there be more than one Session (with the same lease) running at the same time?

[SimFG]

maybe you can try concurrency.NewSession(cli, concurrency.WithLease(leaseId)), like:

session, err := concurrency.NewSession(cli)
newSession, nerr := concurrency.NewSession(cli, concurrency.WithLease(session.Lease()))

see more detail:

etcd/tests/integration/v3_election_test.go

Lines 239 to 282 in 248f072

	func TestElectionOnSessionRestart(t *testing.T) {
	integration.BeforeTest(t)
	clus := integration.NewCluster(t, &integration.ClusterConfig{Size: 1})
	defer clus.Terminate(t)
	cli := clus.RandClient()
	session, err := concurrency.NewSession(cli)
	if err != nil {
	t.Fatal(err)
	}
	e := concurrency.NewElection(session, "test-elect")
	if cerr := e.Campaign(context.TODO(), "abc"); cerr != nil {
	t.Fatal(cerr)
	}
	// ensure leader is not lost to waiter on fail-over
	waitSession, werr := concurrency.NewSession(cli)
	if werr != nil {
	t.Fatal(werr)
	}
	defer waitSession.Orphan()
	waitCtx, waitCancel := context.WithTimeout(context.TODO(), 5*time.Second)
	defer waitCancel()
	go concurrency.NewElection(waitSession, "test-elect").Campaign(waitCtx, "123")
	// simulate restart by reusing the lease from the old session
	newSession, nerr := concurrency.NewSession(cli, concurrency.WithLease(session.Lease()))
	if nerr != nil {
	t.Fatal(nerr)
	}
	defer newSession.Orphan()
	newElection := concurrency.NewElection(newSession, "test-elect")
	if ncerr := newElection.Campaign(context.TODO(), "def"); ncerr != nil {
	t.Fatal(ncerr)
	}
	ctx, cancel := context.WithTimeout(context.TODO(), 5*time.Second)
	defer cancel()
	if resp := <-newElection.Observe(ctx); len(resp.Kvs) == 0 || string(resp.Kvs[0].Value) != "def" {
	t.Errorf("expected value=%q, got response %v", "def", resp)
	}
	}