restart an upstart script when there is an inotify event

watchfiles.go

// this is almost complete :)
// name: watchfiles.go
// purpose: emit a restart
package main

import (
  "log"                               // printing
  "code.google.com/p/go.exp/inotify"  // inotify events
  "os"                                // argument handling
  "os/exec"                           // used to call initctl restart process name
)

func main() {
  args := os.Args[:]
  if len(args) == 3 {
    file := args[1]
    job  := args[2]
    log.Printf("Gophers now Watching your file:\033[35m %s \033[0m\nWhen Changed,\033[34m %s, \033[0m will be restarted\n", file, job)
    watch(file, job)
  } else {
    log.Printf("usage: \033[34mwatchfiles\033[0m file_to_watch upstart_job\n")
  }
}

func restartJob(file string, job string) {
  out, err := exec.Command("restart", job).Output()
  if err != nil {
    log.Println("ERR: restart job failed")
    log.Println(out)
    log.Fatal(err)
  }
  log.Printf("Result Of Command:\n%s\n", out)
}

func watch(file string, job string) {
  watcher, err := inotify.NewWatcher()
  if err != nil {
    log.Fatal(err)
  }
  err = watcher.Watch(file)
  if err != nil {
    log.Fatal(err)
  }
  for {
    select {
      case ev := <-watcher.Event:
        log.Println("Event:", ev)
        restartJob(file, job)
      case  err := <-watcher.Error:
        log.Println("Error:", err)
    }
  }
}

Usage: sudo watchfiles /path/to/project/.git upstart_job_name