//在连接池取一个新连接
//
// 返回 client，一个新的连接
// 返回 err，可能的错误，操作成功返回 nil
func (this *Connectors) NewClient() (*Client, error) {
if err := this.checkNew(); err != nil {
return nil, err
}
this.lock.Lock()
this.WaitCount += 1
this.lock.Unlock()
timeout := time.After(time.Duration(this.cfg.GetClientTimeout) * time.Second)
select {
case <-timeout:
return nil, goerr.New("ssdb pool is busy,can not get new client in %d seconds", this.cfg.GetClientTimeout)
case c := <-this.pool:
if c == nil {
return nil, goerr.New("the Connectors is Closed, can not get new client.")
}
this.lock.Lock()
this.WaitCount -= 1
this.ActiveCount += 1
this.Size -= 1
this.poolMap[c] = true
this.lock.Unlock()
return c, nil
}
}
//检查是否可以创建新连接，是否需要增加连接数
//
// 返回 err，可能的错误，操作成功返回 nil
func (this *Connectors) checkNew() error {
this.lock.Lock()
defer this.lock.Unlock()
switch this.Status {
case PoolStop:
return goerr.New("the Connectors is Closed, can not get new client.")
case PoolInit:
return goerr.New("the Connectors is not inited, can not get new client.")
}
if this.WaitCount >= this.cfg.MaxWaitSize {
return goerr.New("ssdb pool is busy,Wait for connection creation has reached %d", this.WaitCount)
}
if this.Size < this.cfg.MinPoolSize && this.Size+this.ActiveCount < this.cfg.MaxPoolSize { //如果没有连接了，检查是否可以自动增加
for i := 0; i < this.cfg.AcquireIncrement; i++ {
c := this.createClient()
if err := c.Start(); err == nil {
this.pool <- c
this.poolMap[c] = false
this.Size += 1
} else {
return err
}
}
}
return nil
}
//生成通过的错误信息，已经确定是有错误
func makeError(resp []string, errKey ...interface{}) error {
if len(resp) < 1 {
return goerr.New("ssdb respone error")
}
//正常返回的不存在不报错，如果要捕捉这个问题请使用exists
if resp[0] == "not_found" {
return nil
}
if len(errKey) > 0 {
return goerr.New("access ssdb error, code is %v, parameter is %v", resp, errKey)
} else {
return goerr.New("access ssdb error, code is %v", resp)
}
}