DMAC/cmd/reactor/main.go

package main

import (
    "fmt"
    "os"
    "flag"
    "log"
    "strings"
    "strconv"
    "FRMS/internal/pkg/reactor"
)

type coordinator interface {
    Start()
}

func NewCoordinator(ip string,port int,ch chan error) coordinator {
    // allows interface checking as opposed to calling directly
    return reactor.NewCoordinator(ip,port,ch)
}

func main() {
    var ip string
    var port int

    flag.Usage = func() {
        w := flag.CommandLine.Output()
        fmt.Fprintf(w, "Usage: %s ip_addr port \n",os.Args[0])
    }
    flag.Parse()
    if flag.NArg() != 2 {
        flag.Usage()
        os.Exit(1)
    }
    args := flag.Args()
    if s := strings.Split(args[0],"."); len(s) != 4 {
        flag.Usage()
        log.Fatal("second arguement must be an ip address of type x.x.x.x")
    }
    if p, err := strconv.Atoi(args[1]);p < 1024 || p > 65535 {
        flag.Usage()
        log.Fatal("Port must be between [1023,65535]")
    } else if err != nil {
        log.Fatal(err)
    }
    ip = args[0]
    port, err := strconv.Atoi(args[1])
    if err != nil {
        log.Fatal(err)
    }
    ch := make(chan error)
    rlc := NewCoordinator(ip,port,ch) // host port
    go rlc.Start()
    err = <-ch
    if err != nil {
        log.Fatal(err)
    }
}