internal/lume: start work on dynamically replacing the zip filesystem for XeDN serving

Signed-off-by: Xe Iaso <me@xeiaso.net>

2 files changed, 73 insertions, 1 deletions

diff --git a/internal/headerparams.go b/internal/headerparams.go
new file mode 100644
index 0000000..ff4e78b
--- /dev/null
+++ b/internal/headerparams.go
@@ -0,0 +1,22 @@
+package internal
+
+import (
+	"strings"
+)
+
+func ParseValueAndParams(value string) map[string]string {
+	parts := strings.Split(value, ",")
+	vals := make(map[string]string)
+
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part == "" {
+			continue
+		}
+
+		parts := strings.Split(part, ";")
+		vals[parts[0]] = strings.Join(parts[1:], ";")
+	}
+
+	return vals
+}
diff --git a/internal/lume/zip.go b/internal/lume/zip.go
index cecfb38..90513fc 100644
--- a/internal/lume/zip.go
+++ b/internal/lume/zip.go
@@ -10,9 +10,14 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
+
+	"xeiaso.net/v4/internal"
 )
 
-const compressionGZIP = 0x69
+const (
+	compressionGZIP = 0x69
+)
 
 func init() {
 	zip.RegisterCompressor(compressionGZIP, func(w io.Writer) (io.WriteCloser, error) {
@@ -163,3 +168,48 @@ func isCompressible(fname string) (bool, error) {
 	// The file is compressible by both its header and name
 	return true, nil
 }
+
+type ZipServer struct {
+	lock sync.RWMutex
+	zip  *zip.ReadCloser
+}
+
+func NewZipServer(zipPath string) (*ZipServer, error) {
+	file, err := zip.OpenReader(zipPath)
+	if err != nil {
+		return nil, err
+	}
+
+	result := &ZipServer{
+		zip: file,
+	}
+
+	return result, nil
+}
+
+func (zs *ZipServer) Update(fname string) error {
+	zs.lock.Lock()
+	defer zs.lock.Unlock()
+
+	old := zs.zip
+
+	file, err := zip.OpenReader(fname)
+	if err != nil {
+		return err
+	}
+
+	zs.zip = file
+
+	old.Close()
+	return nil
+}
+
+func (zs *ZipServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	zs.lock.RLock()
+	defer zs.lock.RUnlock()
+
+	vals := internal.ParseValueAndParams(r.Header.Get("Accept-Encoding"))
+	slog.Info("accept-encoding", "vals", vals)
+
+	http.FileServer(http.FS(zs.zip)).ServeHTTP(w, r)
+}