go-captiveportal/middleware.go

package captiveportal

import (
	"net/http"

	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
)

func (s *Service) Middleware() func(next http.Handler) http.Handler {
	registry := s.registry
	matcher := s.options.Matcher
	liar := s.options.Liar

	return func(next http.Handler) http.Handler {
		fn := func(w http.ResponseWriter, r *http.Request) {
			ctx := r.Context()

			matches, os, err := matcher.Match(r)
			if err != nil {
				panic(errors.WithStack(err))
			}

			logger.Debug(
				ctx, "applied captive portal matching",
				logger.F("os", os),
				logger.F("url", r.URL.String()),
				logger.F("host", r.Host),
				logger.F("matches", matches),
			)

			if !matches {
				next.ServeHTTP(w, r)

				return
			}

			id, err := s.identifier.Identify(r)
			if err != nil {
				panic(errors.Wrap(err, ErrClientIdentificationFailed.Error()))
			}

			logger.Debug(
				ctx, "identified captive portal client",
				logger.F("remoteAddr", r.RemoteAddr),
				logger.F("id", id),
			)

			registry.Touch(id, os)

			if registry.IsLying(id) {
				logger.Debug(
					ctx, "lying to captive portal client",
					logger.F("remoteAddr", r.RemoteAddr),
					logger.F("id", id),
				)

				liar.Handle(os, w, r)

				return
			}

			if registry.IsCaptive(id) {
				logger.Debug(
					ctx, "capture captive portal client",
					logger.F("remoteAddr", r.RemoteAddr),
					logger.F("id", id),
				)

				// Redirect to configured URL
				http.Redirect(w, r, s.redirectURL, http.StatusTemporaryRedirect)

				return
			}

			next.ServeHTTP(w, r)
		}

		return http.HandlerFunc(fn)
	}
}