You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: run_server.go
    path of file: ./repos/go-oauth2-server/cmd
    
    the code of the file until where you have to start completion: package cmd

import (
	"net/http"
	"time"

	"github.com/RichardKnop/go-oauth2-server/services"
	"github.com/gorilla/mux"
	"github.com/phyber/negroni-gzip/gzip"
	"github.com/urfave/negroni"
	"gopkg.in/tylerb/graceful.v1"
)

// RunServer runs the app
func RunServer(configBackend string) error {
	cnf, db, err := initConfigDB(true, true, configBackend)
	if err != nil {
		return err
	}
	defer db.Close()

	// start the services
	if err := services.Init(cnf, db); err != nil {
		
    
func RunServer(configBackend string) error {
	cnf, db, err := initConfigDB(true, true, configBackend)
	if err != nil {
		return err
	}
	defer db.Close()

	// start the services
	if err := services.Init(cnf, db); err != nil {
		return err
	}
	defer services.Close()

	// Start a classic negroni app
	app := negroni.New()
	app.Use(negroni.NewRecovery())
	app.Use(negroni.NewLogger())
	app.Use(gzip.Gzip(gzip.DefaultCompression))
	app.Use(negroni.NewStatic(http.Dir("public")))

	// Create a router instance
	router := mux.NewRouter()

	// Add routes
	services.HealthService.RegisterRoutes(router, "/v1")
	services.OauthService.RegisterRoutes(router, "/v1/oauth")
	services.WebService.RegisterRoutes(router, "/web")

	// Set the router
	app.UseHandler(router)

	// Run the server on port 8080, gracefully stop on SIGTERM signal
	graceful.Run(":8080", 5*time.Second, app)

	return nil
}