httpserver/http.go

package httpserver

import (
	"context"
	"crypto/tls"
	"html/template"
	"net"
	"net/http"
	"sync"

	"github.com/gin-gonic/gin"
	"github.com/phuslu/log"
	"go.sebtobie.de/httpserver/auth"
	"go.sebtobie.de/httpserver/menus"
	"go.sebtobie.de/httpserver/templates"
)

func init() {
	gin.DebugPrintRouteFunc = func(httpMethod, absolutePath, handlerName string, nuHandlers int) {
		log.Trace().Msgf("%-4s(%02d): %-20s %s", httpMethod, nuHandlers, absolutePath, handlerName)
	}
}

// Config that is used to map the toml config to the settings that are used.
type Config struct {
	Addr      []string
	TLSAddr   []string
	TLSconfig *tls.Config
	Certfile  string
	Keyfile   string
	Sites     map[string]SiteConfig
}

// MarshalObject adds the information over the object to the *log.Entry
func (c *Config) MarshalObject(e *log.Entry) {
	e.Strs("Address", c.Addr).Bool("TLS", c.TLSconfig != nil)
	if c.TLSconfig != nil {
		e.Str("Certfile", c.Certfile)
		e.Str("Keyfile", c.Keyfile)
	}
}

var _ log.ObjectMarshaler = &Config{}

// Server is an wrapper for the *http.Server and *gin.Engine
type Server struct {
	http            *http.Server
	Conf            *Config
	mrouter         map[string]*gin.Engine
	sites           map[string]Site
	menu            []menus.Menu
	template        template.Template
	NotFoundHandler http.Handler
	routines        sync.WaitGroup
	setup           bool
	authh           auth.AuthenticationHandler
}

// CreateServer creates an server that can be run in a coroutine.
func CreateServer() *Server {
	log.Info().Msg("Redirect logging output to phuslu/log")
	gin.DefaultErrorWriter = log.DefaultLogger.Std(log.ErrorLevel, log.Context{}, "GIN", 0).Writer()
	gin.DefaultWriter = log.DefaultLogger.Std(log.DebugLevel, log.Context{}, "GIN", 0).Writer()
	log.Info().Msg("Creating HTTP-Server")
	var server = &Server{
		Conf:            &Config{},
		mrouter:         map[string]*gin.Engine{},
		authh:           &auth.AnonAccountHandler{},
		menu:            []menus.Menu{},
		NotFoundHandler: http.NotFoundHandler(),
	}
	server.http = &http.Server{
		ErrorLog: log.DefaultLogger.Std(log.ErrorLevel, log.Context{}, "", 0),
		Handler:  http.HandlerFunc(server.DomainRouter),
	}
	return server
}

// runPort runs a listener on the port. his enables th server to serve more than a address.
func (s *Server) runPort(address string, tls bool) {
	var socket net.Listener
	var err error
	if net.ParseIP(address) != nil {
		socket, err = net.Listen("tcp", address)
	} else {
		socket, err = net.Listen("unix", address)
	}
	if err != nil {
		log.Error().Err(err).Msgf("failed to open socket on %s", address)
	}
	if tls {
		err = s.http.ServeTLS(socket, s.Conf.Certfile, s.Conf.Keyfile)
	} else {
		err = s.http.Serve(socket)
	}
	if err != http.ErrServerClosed {
		log.Error().Err(err).Msg("Socket unexpected exited")
	}
	s.routines.Done()
}

// SetAuthentication sets the handler that is responsible for authentication
func (s *Server) SetAuthentication(a auth.AuthenticationHandler) {
	s.authh = a
}

// StartServer starts the server as configured and sends the errormessage to the log.
// it blocks until all ports are closed.
func (s *Server) StartServer() {
	if !s.setup {
		log.Error().Msg("Server not set up")
		return
	}
	log.Info().Msg("Starting server")
	s.http.TLSConfig = s.Conf.TLSconfig
	var err error
	if s.Conf.Certfile != "" && s.Conf.Keyfile != "" {
		for _, addr := range s.Conf.TLSAddr {
			s.routines.Add(1)
			go s.runPort(addr, true)
		}
	}
	for _, addr := range s.Conf.Addr {
		go s.runPort(addr, false)
	}
	if err != http.ErrServerClosed {
		log.Error().Err(err).Msg("Server unexpected exited")
	}
	s.routines.Wait()
}

// DomainRouter redirects the requests to the routers of the domains
func (s *Server) DomainRouter(w http.ResponseWriter, r *http.Request) {
	var domain string
	if r.URL.Host != "" {
		domain = r.URL.Host
	} else if r.Host != "" {
		domain = r.Host
	} else if r.Header.Get("X-Original-Host") != "" {
		domain = r.Header.Get("X-Original-Host")
	}
	r.Host = domain
	r.URL.Host = domain
	for header, value := range map[string][]string(r.Header) {
		log.Trace().Strs(header, value).Msg("Headers")
	}
	if router, found := s.mrouter[domain]; found {
		router.NoMethod(gin.WrapH(s.NotFoundHandler))
		router.NoRoute(gin.WrapH(s.NotFoundHandler))
		router.ServeHTTP(w, r)
		return
	}
	var entrys []string
	for d := range s.mrouter {
		entrys = append(entrys, d)
	}
	log.Trace().Strs("reqistred domains", entrys).Msg("domain not found")
	s.NotFoundHandler.ServeHTTP(w, r)
}

// Use installs the middleware into the router.
// The Middleware must be able to detect multiple calls byy itself. Deduplication is not performed.
func (s *Server) Use(m ...gin.HandlerFunc) {
	for _, router := range s.mrouter {
		router.Use(m...)
	}
}

// Stop Shuts the Server down
func (s *Server) Stop(ctx context.Context) {
	log.Info().Err(s.http.Shutdown(ctx)).Msg("Server Shut down.")
	for _, s := range s.sites {
		s.Teardown()
	}
}

func (s *Server) menus() []menus.Menu {
	return s.menu
}

// Setup ets the server up. It loads the sites and prepare the server for startup.
// The sites get their config in this step.
func (s *Server) Setup() {
	var router *gin.Engine
	var found bool
	for cfg, site := range s.sites {
		config := s.Conf.Sites[cfg]
		if router, found = s.mrouter[config.Domain()]; !found {
			router = gin.New()
			mw := []gin.HandlerFunc{
				func(c *gin.Context) {
					c.Set(Menus, s.menus)
					c.Set(Domain, config.Domain())
				},
			}
			mw = append(mw, func(c *gin.Context) { s.authh.Account(c) })
			router.Use(mw...)
			s.mrouter[config.Domain()] = router
		}
		site.Init(router.Group(config.Path()))
		if ms, ok := site.(menus.MenuSite); ok {
			menus := ms.Menu(config.Domain())
			log.Debug().Msgf("%d menus are added", len(menus))
			s.menu = append(s.menu, menus...)
		}
		if ts, ok := site.(templates.TemplateSite); ok {
			templates := ts.Templates()
			log.Debug().Msgf("Templates for %s%s are added", config.Domain(), config.Path())
			s.template.AddParseTree(templates.Name(), templates.Tree)
			s.template.Funcs(ts.Funcs())
		}
	}
	s.setup = true
}

// RegisterSite adds an site to the engine as its own grouo
// it registers the defaults so that the application can load/dump it from/into an configfile or commandline options
func (s *Server) RegisterSite(cfg string, site Site) {
	var config = site.Defaults()
	s.Conf.Sites[cfg] = config
	s.sites[cfg] = site
}