From 38fb02f470c32cf2a3f4cb9bef540840d85f9254 Mon Sep 17 00:00:00 2001
From: Alan Pearce
Date: Sun, 23 Jun 2024 19:32:40 +0200
Subject: fix and simplify content-encoding negotiation

---
 internal/website/filemap.go | 18 +++++++++++++-----
 internal/website/mux.go     |  6 ++----
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/internal/website/filemap.go b/internal/website/filemap.go
index 126b67f..1ca242e 100644
--- a/internal/website/filemap.go
+++ b/internal/website/filemap.go
@@ -16,12 +16,19 @@ import (
 )
 
 type File struct {
-	filename     string
 	contentType  string
 	etag         string
 	alternatives map[string]string
 }
 
+func (f *File) AvailableEncodings() []string {
+	encs := []string{}
+	for enc := range f.alternatives {
+		encs = append(encs, enc)
+	}
+	return encs
+}
+
 var files = map[string]*File{}
 
 func hashFile(filename string) (string, error) {
@@ -49,10 +56,11 @@ func registerFile(urlpath string, fp string) error {
 		return err
 	}
 	f := File{
-		filename:     fp,
-		contentType:  mime.TypeByExtension(filepath.Ext(fp)),
-		etag:         hash,
-		alternatives: map[string]string{},
+		contentType: mime.TypeByExtension(filepath.Ext(fp)),
+		etag:        hash,
+		alternatives: map[string]string{
+			"identity": fp,
+		},
 	}
 	for enc, suffix := range encodings {
 		_, err := os.Stat(fp + suffix)
diff --git a/internal/website/mux.go b/internal/website/mux.go
index 2d0a830..4cc013e 100644
--- a/internal/website/mux.go
+++ b/internal/website/mux.go
@@ -80,15 +80,13 @@ func NewMux(cfg *config.Config, root string) (mux *http.ServeMux, err error) {
 		for k, v := range cfg.Extra.Headers {
 			w.Header().Add(k, v)
 		}
-		enc := nego.NegotiateContentEncoding(r, "br", "gzip")
+		enc := nego.NegotiateContentEncoding(r, file.AvailableEncodings()...)
 		switch enc {
-		case "", "identity":
-			http.ServeFile(w, r, files[urlPath].filename)
 		case "br", "gzip":
 			w.Header().Add("Content-Encoding", enc)
 			w.Header().Add("Content-Type", file.contentType)
-			http.ServeFile(w, r, files[urlPath].alternatives[enc])
 		}
+		http.ServeFile(w, r, files[urlPath].alternatives[enc])
 
 		return nil
 	}))
-- 
cgit 1.4.1