feat(serverHandler): output response body only if necessary

For methdos like HEAD, OPTIONS, CONNECT and TRACE,
prevent output response body.

Author: marjune163

src/serverHandler/archiveTar.go

@@ -55,6 +55,10 @@ func (h *handler) tar(w http.ResponseWriter, r *http.Request, pageData *response
 	filename := pageData.ItemName + ".tar"
 	writeArchiveHeader(w, "application/octet-stream", filename)
 
+	if !needResponseBody(r.Method) {
+		return
+	}
+
 	h.visitFs(
 		h.root+pageData.handlerReqPath,
 		pageData.rawReqPath,
@@ -88,6 +92,10 @@ func (h *handler) tgz(w http.ResponseWriter, r *http.Request, pageData *response
 	filename := pageData.ItemName + ".tar.gz"
 	writeArchiveHeader(w, "application/octet-stream", filename)
 
+	if !needResponseBody(r.Method) {
+		return
+	}
+
 	h.visitFs(
 		h.root+pageData.handlerReqPath,
 		pageData.rawReqPath,

src/serverHandler/archiveZip.go

@@ -54,6 +54,10 @@ func (h *handler) zip(w http.ResponseWriter, r *http.Request, pageData *response
 	filename := pageData.ItemName + ".zip"
 	writeArchiveHeader(w, "application/zip", filename)
 
+	if !needResponseBody(r.Method) {
+		return
+	}
+
 	h.visitFs(
 		h.root+pageData.handlerReqPath,
 		pageData.rawReqPath,

src/serverHandler/assert.go

@@ -13,5 +13,7 @@ func (h *handler) assert(w http.ResponseWriter, r *http.Request, assertPath stri
 
 	header := w.Header()
 	header.Set("Content-Type", content.ContentType)
-	http.ServeContent(w, r, assertPath, initTime, content.ReadSeeker)
+	if needResponseBody(r.Method) {
+		http.ServeContent(w, r, assertPath, initTime, content.ReadSeeker)
+	}
 }

src/serverHandler/content.go

@@ -0,0 +1,11 @@
+package serverHandler
+
+import "net/http"
+
+func (h *handler) content(w http.ResponseWriter, r *http.Request, data *responseData) {
+	if needResponseBody(r.Method) {
+		item := data.Item
+		file := data.File
+		http.ServeContent(w, r, item.Name(), item.ModTime(), file)
+	}
+}

src/serverHandler/main.go

@@ -74,9 +74,6 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	if data.CanCors {
 		h.cors(w, r)
-		if r.Method == "OPTIONS" {
-			return
-		}
 	}
 
 	if data.CanArchive && len(r.URL.RawQuery) > 0 {
@@ -95,11 +92,10 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	item := data.Item
 	if file != nil && item != nil && !item.IsDir() {
-		http.ServeContent(w, r, item.Name(), item.ModTime(), file)
-		return
+		h.content(w, r, data)
+	} else {
+		h.page(w, r, data)
 	}
-
-	h.page(w, r, data)
 }
 
 func NewHandler(

src/serverHandler/page.go

@@ -15,6 +15,8 @@ func (h *handler) page(w http.ResponseWriter, r *http.Request, data *responseDat
 		w.WriteHeader(http.StatusOK)
 	}
 
-	err := h.template.Execute(w, data)
-	h.errHandler.LogError(err)
+	if needResponseBody(r.Method) {
+		err := h.template.Execute(w, data)
+		h.errHandler.LogError(err)
+	}
 }

src/serverHandler/util.go

@@ -0,0 +1,5 @@
+package serverHandler
+
+func needResponseBody(method string) bool {
+	return method != "HEAD" && method != "OPTIONS" && method != "CONNECT" && method != "TRACE"
+}