router.go

package main

import (
	"context"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/chainreaction/api"
	"github.com/chainreaction/datastore"
	"github.com/gin-gonic/gin"
)

func setupRouter() *gin.Engine {
	router := gin.Default()
	router.GET("/new", api.CreateNewGame)
	// here it is /games/:name due to limitation of httprouter used by gin because
	// it doesn't support wildcard and static route at the same position
	// i.e no support for /login and /:userid as they conflict
	router.GET("/games/:name/join", api.JoinExistingGame)
	router.GET("/games/:name/play", api.StartGamePlay)

	return router
}

func main() {
	router := setupRouter()
	go datastore.Cleanup()
	s := &http.Server{
		Addr:           ":8080",
		Handler:        router,
		ReadTimeout:    10 * time.Second,
		WriteTimeout:   10 * time.Second,
		MaxHeaderBytes: 1 << 20,
	}
	// Initializing the server in a goroutine so that
	// it won't block the graceful shutdown handling below
	go func() {
		if err := s.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("listen: %s\n", err)
		}
	}()

	// Wait for interrupt signal to gracefully shutdown the server with
	// a timeout of 5 seconds.
	quit := make(chan os.Signal)
	// kill (no param) default send syscall.SIGTERM
	// kill -2 is syscall.SIGINT
	// kill -9 is syscall.SIGKILL but can't be catch, so don't need add it
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit
	log.Println("Shutting down server...")

	// The context is used to inform the server it has 5 seconds to finish
	// the request it is currently handling
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if err := s.Shutdown(ctx); err != nil {
		log.Fatal("Server forced to shutdown:", err)
	}

	log.Println("Server exiting")

}