Add custom middleware to strip slashes

CHANGELOG.md

@@ -32,6 +32,7 @@
 - Dev: Don't use `stampede` for link resolver links. (#394)
 - Dev: Update to Twitter's v2 API. (#414)
 - Dev: Add HTTP Caching headers. (#417)
+- Dev: Add custom middleware to strip trailing slashes. (#422)
 - Dev: Make cache timeout durations configurable. (#419)
 
 ## 1.2.3

cmd/api/main.go

@@ -20,7 +20,6 @@ import (
 	"github.com/Chatterino/api/pkg/resolver"
 	"github.com/Chatterino/api/pkg/thumbnail"
 	"github.com/go-chi/chi/v5"
-	"github.com/go-chi/chi/v5/middleware"
 	"go.uber.org/zap"
 )
 
@@ -119,7 +118,7 @@ func main() {
 	router := chi.NewRouter()
 
 	// Strip trailing slashes from API requests
-	router.Use(middleware.StripSlashes)
+	router.Use(StripSlashes)
 
 	var helixUsernameCache cache.Cache
 
@@ -145,3 +144,18 @@ func main() {
 
 	listen(ctx, cfg.BindAddress, mountRouter(router, cfg, log), log)
 }
+
+// StripSlashes strips slashes at the end of a request.
+// The StripSlashes middleware provided in chi has a bug, so a custom solution has to be used
+// TODO: can be switched to chi middleware,
+// if bug described in https://github.com/Chatterino/api/pull/422 is fixed
+func StripSlashes(next http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+		path := r.URL.Path
+		if len(path) > 1 && path[len(path)-1] == '/' {
+			r.URL.Path = path[:len(path)-1]
+		}
+		next.ServeHTTP(w, r)
+	}
+	return http.HandlerFunc(fn)
+}