wrouter/router.go

package wrouter

import (
	"fmt"
	"net/http"
	"strings"

	"git.aiterp.net/gisle/notebook3/session"

	"git.aiterp.net/gisle/wrouter/auth"
)

type Route interface {
	Handle(path string, w http.ResponseWriter, req *http.Request, user *auth.User) bool
}

type Router struct {
	paths  map[Route]string
	routes []Route
}

func (router *Router) Route(path string, route Route) {
	if router.paths == nil {
		router.paths = make(map[Route]string, 16)
	}

	router.paths[route] = path
	router.routes = append(router.routes, route)
}

func (router *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
	defer req.Body.Close()

	// Allow REST for clients of yore
	if req.Header.Get("X-Method") != "" {
		req.Method = strings.ToUpper(req.Header.Get("X-Method"))
	}

	// Resolve session cookies
	var user *auth.User
	cookie, err := req.Cookie(session.CookieName)
	if cookie != nil && err == nil {
		sess := auth.FindSession(cookie.Value)
		if sess != nil {
			user = auth.FindUser(sess.UserID)
		}
	}

	for index, route := range router.routes {
		path := router.paths[route]

		if strings.HasPrefix(strings.ToLower(req.URL.Path), path) {
			// Just so the handler can replace the path properly in case of case
			// insensitive clients getting fancy on it.
			path = req.URL.Path[:len(path)]

			// Attach a little something for testing
			w.Header().Set("X-Route-Path", path)
			w.Header().Set("X-Route-Index", fmt.Sprint(index))

			if route.Handle(path, w, req, user) {
				return
			}
		}
	}

	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
	w.WriteHeader(404)
}

func (router *Router) Listen(host string, port int) error {
	return http.ListenAndServe(fmt.Sprintf("%s:%d", host, port), router)
}