docker-nginx-restarter/hupper.go

package main

import (
	"flag"
	"fmt"
	"golang.org/x/exp/inotify"
	"strings"
)

type arrayFlags []string

func (i *arrayFlags) String() string {
	return strings.Join(*i, ", ")
}

func (i *arrayFlags) Set(value string) error {
	*i = append(*i, value)
	return nil
}

func main() {
	var paths arrayFlags
	var container string

	flag.Var(&paths, "path", "Path to monitor for changes (may be specified multiple times)")
	flag.StringVar(&container, "container", "nginx", "Name of the container in which nginx is running")
	flag.Parse()

	fmt.Printf("Hello, world.\nPaths: %v\nContainer: %v\n", paths, container)

	if len(paths) == 0 {
		panic("No paths specified")
	}

	watch_for_changes(paths)
}

func watch_for_changes(paths []string) {
	watcher, err := inotify.NewWatcher()
	if err != nil {
		panic(err)
	}

	defer watcher.Close()

	for _, path := range paths {
		watcher.Watch(path)
	}

	for {
		select {
		case event := <-watcher.Event:
			panic(event)
		case err := <-watcher.Error:
			panic(err)
		}
	}
}