perf(serverHandler/responseData): provide status instead of detail errors

Providing response status directly, instead of giving out errors
information and calculate response status according to them.

BREAKING CHANGE:

Root fields passing to template changed.

before:

```
{{if .HasForbiddenError}}...{{end}}
{{if .HasNotFoundError}}...{{end}}
{{if .HasInternalError}}...{{end}}
```

after:

```
{{if eq .Status 403}}...{{end}}
{{if eq .Status 404}}...{{end}}
{{if eq .Status 500}}...{{end}}
```

Author: marjune163

src/serverHandler/content.go

@@ -42,10 +42,9 @@ func (h *handler) content(w http.ResponseWriter, r *http.Request, data *response
 		header.Set("Content-Length", strconv.FormatInt(item.Size(), 10))
 		header.Set("Date", time.Now().UTC().Format(http.TimeFormat))
 		header.Set("Last-Modified", item.ModTime().UTC().Format(http.TimeFormat))
-	} else {
-		// take effect only if (!HasForbiddenError && !HasNotFoundError)
-		data.HasInternalError = true
+	} else if data.Status == http.StatusOK {
+		data.Status = http.StatusInternalServerError
 	}
 
-	writeHeader(w, r, data)
+	w.WriteHeader(data.Status)
 }

src/serverHandler/json.go

@@ -15,10 +15,6 @@ type jsonItem struct {
 }
 
 type jsonResponseData struct {
-	ForbiddenError bool `json:"forbiddenError"`
-	NotFoundError  bool `json:"notFoundError"`
-	InternalError  bool `json:"internalError"`
-
 	Item     *jsonItem   `json:"item"`
 	SubItems []*jsonItem `json:"subItems"`
 }
@@ -48,11 +44,8 @@ func getJsonData(data *responseData) *jsonResponseData {
 	}
 
 	return &jsonResponseData{
-		ForbiddenError: data.HasForbiddenError,
-		NotFoundError:  data.HasNotFoundError,
-		InternalError:  data.HasInternalError,
-		Item:           item,
-		SubItems:       subItems,
+		Item:     item,
+		SubItems: subItems,
 	}
 }
 
@@ -61,7 +54,7 @@ func (h *handler) json(w http.ResponseWriter, r *http.Request, data *responseDat
 	header.Set("Content-Type", "application/json; charset=utf-8")
 	header.Set("Cache-Control", "public, max-age=0")
 
-	writeHeader(w, r, data)
+	w.WriteHeader(data.Status)
 
 	if needResponseBody(r.Method) {
 		jsonData := getJsonData(data)

src/serverHandler/page.go

@@ -7,7 +7,7 @@ func (h *handler) page(w http.ResponseWriter, r *http.Request, data *responseDat
 	header.Set("Content-Type", "text/html; charset=utf-8")
 	header.Set("Cache-Control", "public, max-age=0")
 
-	writeHeader(w, r, data)
+	w.WriteHeader(data.Status)
 
 	if needResponseBody(r.Method) {
 		updateSubsItemHtml(data.SubItems)

src/serverHandler/responseData.go

@@ -40,10 +40,8 @@ type responseData struct {
 	rawReqPath     string
 	handlerReqPath string
 
-	errors            []error
-	HasForbiddenError bool
-	HasNotFoundError  bool
-	HasInternalError  bool
+	errors []error
+	Status int
 
 	IsRoot        bool
 	Path          string
@@ -259,6 +257,18 @@ func sortSubItems(subItems []*subItem) {
 		},
 	)
 }
+func getStatusByErr(err error) int {
+	switch {
+	case os.IsPermission(err):
+		return http.StatusForbidden
+	case os.IsNotExist(err):
+		return http.StatusNotFound
+	case err != nil:
+		return http.StatusInternalServerError
+	default:
+		return http.StatusOK
+	}
+}
 
 func (h *handler) getResponseData(r *http.Request) (data *responseData) {
 	requestUri := r.URL.Path
@@ -267,10 +277,7 @@ func (h *handler) getResponseData(r *http.Request) (data *responseData) {
 	rawReqPath := util.CleanUrlPath(requestUri)
 	reqPath := util.CleanUrlPath(rawReqPath[len(h.urlPrefix):]) // strip url prefix path
 	errs := []error{}
-	forbidden := false
-	notFound := false
-	internalError := false
-
+	status := http.StatusOK
 	isRoot := rawReqPath == "/"
 
 	pathEntries := getPathEntries(rawReqPath, tailSlash)
@@ -289,28 +296,21 @@ func (h *handler) getResponseData(r *http.Request) (data *responseData) {
 	file, item, _statErr := stat(reqFsPath, !h.emptyRoot)
 	if _statErr != nil {
 		errs = append(errs, _statErr)
-		switch {
-		case os.IsPermission(_statErr):
-			forbidden = true
-		case os.IsNotExist(_statErr):
-			notFound = true
-		default:
-			internalError = true
-		}
+		status = getStatusByErr(_statErr)
 	}
 
 	itemName := getItemName(item, r)
 
 	subInfos, _readdirErr := readdir(file, item, needResponseBody(r.Method))
 	if _readdirErr != nil {
 		errs = append(errs, _readdirErr)
-		internalError = true
+		status = http.StatusInternalServerError
 	}
 
 	_mergeErrs := h.mergeAlias(rawReqPath, &subInfos)
 	if len(_mergeErrs) > 0 {
 		errs = append(errs, _mergeErrs...)
-		internalError = true
+		status = http.StatusInternalServerError
 	}
 
 	subInfos = h.FilterItems(subInfos)
@@ -329,10 +329,8 @@ func (h *handler) getResponseData(r *http.Request) (data *responseData) {
 		rawReqPath:     rawReqPath,
 		handlerReqPath: reqPath,
 
-		errors:            errs,
-		HasForbiddenError: forbidden,
-		HasNotFoundError:  notFound,
-		HasInternalError:  internalError,
+		errors: errs,
+		Status: status,
 
 		IsRoot:        isRoot,
 		Path:          rawReqPath,

src/serverHandler/writeHeader.go

@@ -56,11 +56,11 @@
 	{{end}}{{end}}
 </ul>
 
-{{if .HasForbiddenError}}
+{{if eq .Status 403}}
 	<div class="error">403 resource is forbidden</div>
-{{else if .HasNotFoundError}}
+{{else if eq .Status 404}}
 	<div class="error">404 resource not found</div>
-{{else if .HasInternalError}}
+{{else if eq .Status 500}}
 	<div class="error">500 potential issue occurred</div>
 {{end}}
 

src/tpl/page.html

@@ -60,11 +60,11 @@ const pageTplStr = `
 </li>
 {{end}}{{end}}
 </ul>
-{{if .HasForbiddenError}}
+{{if eq .Status 403}}
 <div class="error">403 resource is forbidden</div>
-{{else if .HasNotFoundError}}
+{{else if eq .Status 404}}
 <div class="error">404 resource not found</div>
-{{else if .HasInternalError}}
+{{else if eq .Status 500}}
 <div class="error">500 potential issue occurred</div>
 {{end}}
 <script type="text/javascript" src="{{.RootRelPath}}?assert=main.js"></script>