server.go

package remote

import (
	"context"
	"net"
	"net/http"
	"time"

	"github.com/creativeprojects/clog"
)

const (
	timeout = 5
)

var (
	listener *net.TCPListener
	port     int
	server   *http.Server
)

// StartServer starts a http server
func StartServer(done chan interface{}) error {
	// let the system chose a port
	addr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:0")
	if err != nil {
		return err
	}
	listener, err = net.ListenTCP("tcp", addr)
	if err != nil {
		return err
	}
	port = listener.Addr().(*net.TCPAddr).Port
	clog.Debugf("listening on port %d", port)

	server = &http.Server{
		Handler:           getServeMux(),
		ReadHeaderTimeout: 30 * time.Second,
	}
	go func() {
		err := server.Serve(listener)
		if err != http.ErrServerClosed {
			clog.Errorf("error starting server: %v", err)
		}
		close(done)
	}()

	return nil
}

// GetPort returns the port chosen by the system
func GetPort() int {
	return port
}

// StopServer gracefully asks the http server to shutdown
func StopServer(ctx context.Context) {
	if server != nil {
		// gracefully stop the http server
		err := server.Shutdown(ctx)
		if err != nil {
			clog.Warningf("error shutting down server: %v", err)
		}
	}
	server = nil
	if listener != nil {
		listener.Close()
	}
	listener = nil
}