package httpserver

import (

"context"

"net"

"net/http"

"os"

"sync"

"time"

"github.com/inconshreveable/log15"

"github.com/sourcegraph/sourcegraph/internal/goroutine"

)

type server struct {

server *http.Server

makeListener func() (net.Listener, error)

once sync.Once

preShutdownPause time.Duration

}

type ServerOptions func(s *server)

func WithPreShutdownPause(d time.Duration) ServerOptions {

return func(s *server) { s.preShutdownPause = d }

}

// New returns a BackgroundRoutine that serves the given server on the given listener.

func New(listener net.Listener, httpServer *http.Server, options ...ServerOptions) goroutine.BackgroundRoutine {

makeListener := func() (net.Listener, error) { return listener, nil }

return newServer(httpServer, makeListener, options...)

}

// New returns a BackgroundRoutine that serves the given handler on the given address.

func NewFromAddr(addr string, httpServer *http.Server, options ...ServerOptions) goroutine.BackgroundRoutine {

makeListener := func() (net.Listener, error) { return NewListener(addr) }

return newServer(httpServer, makeListener, options...)

}

func newServer(httpServer *http.Server, makeListener func() (net.Listener, error), options ...ServerOptions) goroutine.BackgroundRoutine {

s := &server{

server: httpServer,

makeListener: makeListener,

}

for _, option := range options {

option(s)

}

return s

}

func (s *server) Start() {

listener, err := s.makeListener()

if err != nil {

log15.Error("Failed to create listener", "error", err)

os.Exit(1)

}

if err := s.server.Serve(listener); err != http.ErrServerClosed {

log15.Error("Failed to start server", "error", err)

os.Exit(1)

}

}

func (s *server) Stop() {

s.once.Do(func() {

if s.preShutdownPause > 0 {

time.Sleep(s.preShutdownPause)

}

ctx, cancel := context.WithTimeout(context.Background(), goroutine.GracefulShutdownTimeout)

defer cancel()

if err := s.server.Shutdown(ctx); err != nil {

log15.Error("Failed to shutdown server", "error", err)

}

})

}