go ssh 执行命令

package main

import (
   "fmt"
   gossh "golang.org/x/crypto/ssh"
   "net"
)

type Cli struct {
   user    string
   pwd     string
   addr    string
   client  *gossh.Client
   session *gossh.Session
   LastResult string     
}

func (c *Cli) Connect() (*Cli,error) {
   config := &gossh.ClientConfig{}
   config.SetDefaults()
   config.User = c.user
   config.Auth = []gossh.AuthMethod{gossh.Password(c.pwd)}
   config.HostKeyCallback = func(hostname string,remote net.Addr,key gossh.PublicKey) error { return nil }
   client,err := gossh.Dial("tcp",c.addr,config)
   if nil != err {
      return c,err
   }
   c.client = client
   return c,nil
}

func (c Cli) Run(shell string) (string,error) {
   if c.client == nil {
      if _,err := c.Connect(); err != nil {
         return "",err
      }
   }
   session,err := c.client.NewSession()
   if err != nil {
      return "",err
   }
   defer session.Close()
   buf,err := session.CombinedOutput(shell)

   c.LastResult = string(buf)
   return c.LastResult,err
}

func main() {
   cli := Cli{
      user:"root",pwd: "xxxxxxxxxxxxxxxxxxxxx",addr: "192.168.100.50:22",}
   output,err := cli.Run("pwd")
   fmt.Printf("%vn%v",output,err)
}