HAProxy Agent

haproxy-agent.go

package main

import (
	// "bytes"
	"bufio"
	_ "database/sql"
	"fmt"
	_ "github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
	"github.com/tanji/mariadb-tools/dbhelper"
	"log"
	"net"
)

var (
	db    *sqlx.DB
	delay int64
)

const port string = "6789"

func main() {
	srv, err := net.Listen("tcp", ":"+port)
	if err != nil {
		log.Fatal(err)
	}
	log.Println("Listening on port", port)
	for {
		conn, err := srv.Accept()
		if err != nil {
			log.Fatal(err)
		}
		go handleRequest(conn)
	}
}

func handleRequest(conn net.Conn) {
	writer := bufio.NewWriter(conn)
	fmt.Fprintln(writer, setWeight())
	writer.Flush()
}

func setWeight() string {
	db, err := sqlx.Connect("mysql", "haproxy_agent:SlaveMonitor@tcp(127.0.0.1:3306)/")
	if err != nil {
		log.Println(err)
		return ""
	}
	defer db.Close()
	ss, err := dbhelper.GetSlaveStatus(db)
	if err != nil {
		log.Fatalln("Slave not configured")
	}
	if ss.Seconds_Behind_Master.Valid == false {
		log.Println("Slave stopped or not setup")
		return "down #slavestopped"
	} else {
		delay = ss.Seconds_Behind_Master.Int64
	}
	log.Printf("Delay: %d", delay)
	if delay < 15 {
		return "up 100%"
	} else if delay >= 15 && delay <= 60 {
		return "up 5%"
	} else {
		return "down #slavedelay"
	}
}