C# IXenConnection.DuplicateSession方法代码示例

        /// <summary>
        /// Try and run the delegate.
        /// If it fails with a web exception or invalid session, try again.
        /// Only retry 60 times. 
        /// </summary>
        /// <param name="connection"></param>
        /// <param name="session"></param>
        /// <param name="f"></param>
        /// <param name="p"></param>
        /// <returns></returns>
        public static Object DoWithSessionRetry(IXenConnection connection, ref Session session, Delegate f, params object[] p)
        {
            int retries = 60;

            while (true)
            {
                try
                {
                    object[] ps = new object[p.Length + 1];

                    ps[0] = session;

                    for (int i = 0; i < p.Length; i++)
                    {
                        ps[i + 1] = p[i];
                    }

                    try
                    {
                        return f.DynamicInvoke(ps);
                    }
                    catch (TargetInvocationException exn)
                    {
                        throw exn.InnerException;
                    }
                }
                catch (WebException we)
                {
                    log.ErrorFormat("WebException in DoWithSessionRetry, retry {0}", retries);
                    log.Error(we, we);

                    if (retries <= 0)
                        throw;
                }
                catch (Failure failure)
                {
                    log.ErrorFormat("Failure in DoWithSessionRetry, retry {0}", retries);
                    log.Error(failure, failure);

                    if (retries <= 0)
                        throw;

                    if (failure.ErrorDescription.Count < 1 || failure.ErrorDescription[0] != XenAPI.Failure.SESSION_INVALID)
                        throw;
                }

                Session newSession = connection.DuplicateSession();

                try
                {
                    // Try and logout the old session using the new session
                    newSession.proxy.session_logout(session.uuid);
                }
                catch
                {
                }

                session = newSession;

                retries--;

                Thread.Sleep(connection.ExpectDisruption ? 500 : 100);
            }
        }

        private Session GetSession(IXenConnection conn)
        {
            // First we look at this.Session. This allows us to sudo if we have only one connection.
            if (Session != null && Session.Connection == conn)
                return Session;

            // Otherwise we dig into our dictionary of sessions for other connections. These cannot be sudo'ed,
            // because there is no good way to make a sudo dialog (or a series of dialogs) for several connections.
            if (Sessions.ContainsKey(conn))
                return Sessions[conn];
            Session s = conn.DuplicateSession();
            Sessions[conn] = s;
            return s;
        }

        /// <summary>
        /// Used for cross connection actions (e.g adding a host to a pool, we need to get a session from the connection we are joining)
        /// Checks to see if we are using elevated credentials for this action. Returns a session using them if they exist, otherwise
        /// using the basic credentials of the _supplied_ IXenConnection. Important - will throw exceptions similar to connection.NewSession
        /// </summary>
        /// <param name="xc"></param>
        /// <returns></returns>
        public Session NewSession(IXenConnection xc)
        {
            if (Connection == null)
                return null;

            if (String.IsNullOrEmpty(sudoPassword) || String.IsNullOrEmpty(sudoUsername))
                return xc.DuplicateSession();

            return xc.ElevatedSession(sudoUsername, sudoPassword);
        }