Serve precompressed files

backend/internal/api/static_handler.go

@@ -0,0 +1,70 @@
+package api
+
+import (
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// StaticHandler serves static files with support for SPA routing and pre-compressed files
+type StaticHandler struct {
+	staticPath string
+}
+
+func NewStaticHandler(staticPath string) *StaticHandler {
+	return &StaticHandler{
+		staticPath: staticPath,
+	}
+}
+
+func (h *StaticHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Get the requested path
+	requestedPath := r.URL.Path
+	fullPath := filepath.Join(h.staticPath, requestedPath)
+	cleanPath := filepath.Clean(fullPath)
+
+	// Security check to prevent directory traversal
+	if !strings.HasPrefix(cleanPath, h.staticPath) {
+		http.Error(w, "Invalid path", http.StatusBadRequest)
+		return
+	}
+
+	// Set cache headers for assets
+	if strings.HasPrefix(requestedPath, "/assets/") {
+		w.Header().Set("Cache-Control", "public, max-age=31536000") // 1 year
+	}
+
+	// Check if file exists (not counting .gz files)
+	stat, err := os.Stat(cleanPath)
+	if err != nil || stat.IsDir() {
+		// Serve index.html for SPA routing
+		indexPath := filepath.Join(h.staticPath, "index.html")
+		http.ServeFile(w, r, indexPath)
+		return
+	}
+
+	// Check for pre-compressed version
+	if strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
+		gzPath := cleanPath + ".gz"
+		if _, err := os.Stat(gzPath); err == nil {
+			w.Header().Set("Content-Encoding", "gzip")
+
+			// Set proper content type based on original file
+			switch filepath.Ext(cleanPath) {
+			case ".js":
+				w.Header().Set("Content-Type", "application/javascript")
+			case ".css":
+				w.Header().Set("Content-Type", "text/css")
+			case ".html":
+				w.Header().Set("Content-Type", "text/html")
+			}
+
+			http.ServeFile(w, r, gzPath)
+			return
+		}
+	}
+
+	// Serve original file
+	http.ServeFile(w, r, cleanPath)
+}