🚧 Trying to setup redirect middleware for Telegram IV

main.go

@@ -13,8 +13,10 @@ import (
 	"log"
 	"net"
 	"net/http"
+	"net/url"
 	"os"
 	"os/signal"
+	"path"
 	"path/filepath"
 	"runtime"
 	"runtime/pprof"
@@ -28,6 +30,7 @@ import (
 
 	"source.toby3d.me/toby3d/home/internal/common"
 	"source.toby3d.me/toby3d/home/internal/domain"
+	"source.toby3d.me/toby3d/home/internal/middleware"
 	"source.toby3d.me/toby3d/home/internal/page"
 	pagefsrepo "source.toby3d.me/toby3d/home/internal/page/repository/fs"
 	pageucase "source.toby3d.me/toby3d/home/internal/page/usecase"
@@ -80,13 +83,10 @@ func NewApp(ctx context.Context, config *domain.Config) (*App, error) {
 	pages := pagefsrepo.NewFileSystemPageRepository(contentDir)
 	pager := pageucase.NewPageUseCase(pages, resources)
 
-	server := &http.Server{
-		Addr: config.AddrPort().String(),
-		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// TODO(toby3d): use exists static use case or split that on static and resource modules?
-			// INFO(toby3d): any static file is public and unprotected by design, so it's safe to search it
-			// first before deep down to any page or it's resource which might be secured by middleware or
-			// something else.
+		// INFO(toby3d): any static file is public and unprotected by design, so it's safe to search it first
+		// before deep down to any page or it's resource which might be secured by middleware or something else.
 		static, err := statics.Get(r.Context(), strings.TrimPrefix(r.URL.Path, "/"))
 		if err == nil {
 			http.ServeContent(w, r, static.Name(), domain.ResourceModTime(static), static)
@@ -190,7 +190,44 @@ func NewApp(ctx context.Context, config *domain.Config) (*App, error) {
 		}); err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 		}
+	})
+
+	mw := middleware.Chain{
+		middleware.Redirect(middleware.RedirectConfig{
+			Code: http.StatusSeeOther,
+			Skipper: func(r *http.Request) bool {
+				return r.UserAgent() != "TelegramBot (like TwitterBot)"
+			},
+		}, func(u *url.URL) (string, bool) {
+			s, err := siter.Do(ctx, domain.LanguageUnd)
+			if err != nil {
+				return "", false
+			}
+
+			if ivHash, ok := s.Params["instantViewHash"].(string); ok {
+				target := &url.URL{
+					Scheme: "https",
+					Host:   "t.me",
+					Path:   path.Join("/share", "url"),
+				}
+
+				q := target.Query()
+
+				q.Set("url", u.String())
+				q.Set("hash", ivHash)
+
+				target.RawQuery = q.Encode()
+
+				return target.String(), ok
+			}
+
+			return "", false
 		}),
+	}
+
+	server := &http.Server{
+		Addr:         config.AddrPort().String(),
+		Handler:      mw.Handler(handler),
 		ErrorLog:     logger,
 		BaseContext:  func(ln net.Listener) context.Context { return ctx },
 		WriteTimeout: 500 * time.Millisecond,