eth-healthcheck/src/cmd/main.go

package main

import (
	"fmt"
	"strings"
	log "github.com/inconshreveable/log15"
	"github.com/pborman/getopt/v2"
	"github.com/onrik/ethrpc"
	"github.com/eosswedenorg-go/haproxy"
	"github.com/eosswedenorg-go/tcp_server"
)

var logger log.Logger

func onConnect(c *tcp_server.Client) {
	logger.Info("Client connected", "addr", c.Addr.String())
}

func onTcpMessage(c *tcp_server.Client, message string) {

	status := haproxy.HealthCheckDown
	client := ethrpc.New(strings.TrimSpace(message))

	resp, err := client.EthSyncing()
	if err == nil {
		if resp.IsSyncing == false {
			status = haproxy.HealthCheckUp
		}
	} else {
		logger.Warn(err.Error())
	}

	logger.Info("Node status", "status", status)

	// Report status to HAproxy
	c.WriteString(fmt.Sprintln(status))
	c.Close()
}

func onDisconnect(c *tcp_server.Client, err error) {
	if err == nil {
		logger.Info("Client disconnected", "addr", c.Addr.String())
	} else {
		logger.Warn("Client disconnected", "addr", c.Addr.String(), "err", err)
	}
}

func argv_listen_addr() string {

	var addr string

	argv := getopt.Args()
	if len(argv) > 0 {
		addr = argv[0]
	} else {
		addr = "127.0.0.1"
	}

	addr += ":"
	if len(argv) > 1 {
		addr += argv[1]
	} else {
		addr += "1301"
	}

	return addr
}

func main() {

    var printVersion bool;
    var printUsage bool;

    getopt.FlagLong(&printUsage, "help", 'h', "Print this help text")
    getopt.FlagLong(&printVersion, "version", 'v', "Print version")

	getopt.Parse()

    if printUsage {
        getopt.Usage()
        return
    }

    if printVersion {
        print("Version: v0.1.0\n")
        return
    }

    logger = log.New()

	addr := argv_listen_addr()
	server := tcp_server.New(argv_listen_addr())

	logger.Info(fmt.Sprintf("Listening on: %s", addr))

	// TCP Client sends message.
	server.OnConnect(onConnect)
	server.OnMessage(onTcpMessage)
	server.OnDisconnect(onDisconnect)

	err := server.Listen()

	if err != nil {
		logger.Error(err.Error())
	}
}