movies/cmd/movies/main.go

package main

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"time"

	"gogs.gildas.ch/gildas/movies"
	"gogs.gildas.ch/gildas/movies/api"
)

const (
	dataFile = "movies.json"
)

func main() {
	var collection *movies.Collection
	if _, err := os.Stat(dataFile); !os.IsNotExist(err) {
		c, err := movies.Import(dataFile)
		if err != nil {
			log.Fatal(err)
		}
		collection = c
	} else {
		collection = &movies.Collection{}
	}

	http.Handle("/add-movie", api.AddMovieHandler(collection))

	port := "8080"
	if p := os.Getenv("PORT"); p != "" {
		port = p
	}

	stopExport := make(chan bool)
	go export(collection, stopExport)
	defer func() { stopExport <- true }()

	fmt.Println("Listening...")
	err := http.ListenAndServe(":"+port, nil)
	fmt.Println("Server stopped with error:", err)
}

func export(c *movies.Collection, stop <-chan bool) {
	for {
		select {
		case <-time.After(30 * time.Second):
			if c.HasChanged() {
				err := c.Export(dataFile)
				if err != nil {
					log.Fatal(err)
					return
				}
				fmt.Printf("Exported fresh data to %q.\n", dataFile)
			}
		case <-stop:
			return
		}
	}
}