How to ping remote mysql using golang - mysql

Question

I am using go to ping some Linux machines.
But it is not work accurate, because it always needs almost 10 seconds to connect the remote mysql.
I use this command:
mysql -u USER -p PASSWORD -h REMOTE_IP
So i want to know how to use linux command to know whether it open or not.
Then I will use golang 's exec.Command to do that .
Here is my ping code:
package main
import (
"errors"
"fmt"
"github.com/tatsushid/go-fastping"
"net"
"net/smtp"
"strings"
"time"
)
func main(){
err := ping("192.168.2.1")
if err != nil{
fmt.Println("WARNING!!!!!!")
}
}
func ping(ip string) error {
p := fastping.NewPinger()
ra, err := net.ResolveIPAddr("ip", ip)
if err != nil {
return err
}
p.AddIPAddr(ra)
found := false
p.OnRecv = func(addr *net.IPAddr, rtt time.Duration) {
found = true
}
err = p.Run()
if err != nil {
return err
}
if !found {
return errors.New("response error")
}
return nil
}

Answer 1

I assume you want to know if mysql is reachable or not. You can use following example:
package main
import (
"database/sql"
"flag"
"fmt"
"log"
_ "github.com/go-sql-driver/mysql"
)
func main() {
var (
server = flag.String("mysql", "localhost:3306", "mysql server")
user = flag.String("user", "root", "mysql user")
pass = flag.String("password", "", "mysql password")
)
flag.Parse()
db, err := sql.Open("mysql", fmt.Sprintf("%s:%s#tcp(%s)/", *user, *pass, *server))
if err != nil {
log.Fatalln(err)
}
defer db.Close()
err = db.Ping()
if err != nil {
log.Fatalln(err)
} else {
log.Println("mysqld is alive")
}
}

Answer 2

If you just need to check connection to a specific host & port, you can do this as:
package main
import (
"fmt"
"net"
)
const (
host = "192.168.2.1"
port = "3306" // default MySQL port
)
func main() {
conn, err := net.Dial("tcp", host+":"+port)
if err != nil {
panic(err)
}
defer conn.Close()
fmt.Printf("Connected to %s \n", conn.RemoteAddr().String())
}