// NewSession gets the leased session for a client.
func NewSession(client *v3.Client) (*Session, error) {
clientSessions.mu.Lock()
defer clientSessions.mu.Unlock()
if s, ok := clientSessions.sessions[client]; ok {
return s, nil
}
resp, err := client.Create(context.TODO(), sessionTTL)
if err != nil {
return nil, err
}
id := lease.LeaseID(resp.ID)
ctx, cancel := context.WithCancel(context.Background())
keepAlive, err := client.KeepAlive(ctx, id)
if err != nil || keepAlive == nil {
return nil, err
}
donec := make(chan struct{})
s := &Session{client: client, id: id, cancel: cancel, donec: donec}
clientSessions.sessions[client] = s
// keep the lease alive until client error or cancelled context
go func() {
defer func() {
clientSessions.mu.Lock()
delete(clientSessions.sessions, client)
clientSessions.mu.Unlock()
close(donec)
}()
for range keepAlive {
// eat messages until keep alive channel closes
}
}()
return s, nil
}