Golang Session.Ping方法代码示例

func FetchStatus(s *Status, ms *mgo.Session, enc encoder.Encoder, r *http.Request) (int, []byte) {
	s.Log["MongoDB"] = NewLog(true, "")
	if err := ms.Ping(); err != nil {
		s.Log["MongoDB"] = NewLog(false, err.Error())
	}
	return http.StatusOK, encoder.Must(enc.Encode(s))
}

func newServer() (*coretesting.MgoInstance, error) {
	inst := &coretesting.MgoInstance{Params: []string{"--replSet", name}}

	err := inst.Start(true)
	if err != nil {
		return nil, fmt.Errorf("Error starting mongo server: %s", err.Error())
	}

	// by dialing right now, we'll wait until it's running
	strategy := utils.AttemptStrategy{Total: time.Second * 5, Delay: time.Millisecond * 100}
	attempt := strategy.Start()
	for attempt.Next() {
		var session *mgo.Session
		session, err = inst.DialDirect()
		if err != nil {
			err = fmt.Errorf("Error dialing mongo server %q: %s", inst.Addr(), err.Error())
		} else {
			session.SetMode(mgo.Monotonic, true)
			err = session.Ping()
			if err != nil {
				err = fmt.Errorf("Error pinging mongo server %q: %s", inst.Addr(), err.Error())
			}
			session.Close()
		}
		if err == nil || !attempt.HasNext() {
			break
		}
	}
	return inst, err
}

// TODO remove dead session from freecon
func (this *Client) checkServerStatus(wg *sync.WaitGroup, sess *mgo.Session) {
	defer wg.Done()
	err := sess.Ping()
	if err != nil {
		log.Error("mongodb err: %v %s", sess.LiveServers(), err)
		sess.Close()
	}
}

// test whether session closed
//
// PS: sometimes it's not corrected
func IsSessionClosed(s *mgo.Session) (res bool) {
	defer func() {
		if err := recover(); err != nil {
			log.Print("[MGO2_IS_SESSION_CLOSED] check session closed panic:", err)
		}
	}()
	res = true
	return s.Ping() != nil
}

func (this *Client) checkServerStatus(wg *sync.WaitGroup, sess *mgo.Session) {
	defer wg.Done()
	err := sess.Ping()
	if err != nil {
		// TODO show mongodb uri in log
		log.Error("mongodb killed for: %s", err)

		sess.Close()
		this.killConn(sess)
	}
}

// applyRelSetConfig applies the new config to the mongo session. It also logs
// what the changes are. It checks if the replica set changes cause the DB
// connection to be dropped. If so, it Refreshes the session and tries to Ping
// again.
func applyRelSetConfig(cmd string, session *mgo.Session, oldconfig, newconfig *Config) error {
	logger.Debugf("%s() changing replica set\nfrom %s\n  to %s",
		cmd, fmtConfigForLog(oldconfig), fmtConfigForLog(newconfig))
	err := session.Run(bson.D{{"replSetReconfig", newconfig}}, nil)
	// We will only try to Ping 2 times
	for i := 0; i < 2; i++ {
		if err == io.EOF {
			// If the primary changes due to replSetReconfig, then all
			// current connections are dropped.
			// Refreshing should fix us up.
			logger.Debugf("got EOF while running %s(), calling session.Refresh()", cmd)
			session.Refresh()
		} else if err != nil {
			// For all errors that aren't EOF, return immediately
			return err
		}
		// err is either nil or EOF and we called Refresh, so Ping to
		// make sure we're actually connected
		err = session.Ping()
		// Change the command because it is the new command we ran
		cmd = "Ping"
	}
	return err
}

func checkSession(s *mgo.Session) (err error) {
	return s.Ping()
}