feat(serverHandler): add downloadfile param

Author: marjune163

doc/en-US/api.md

@@ -39,6 +39,7 @@ curl 'http://localhost/ghfs/?json'
 # Render page for downloading
 ```
 GET <path>?download[&sort=key]
+GET <path>?downloadfile[&sort=key]
 ```
 Similar to regular page rendering, but hide path list,
 sortable list header,
@@ -50,10 +51,14 @@ Example:
 wget --recursive -nc -nH -np 'http://localhost/dir/?download'
 ```
 
+Option `downloadfile` makes file links downloadable instead of displaying content.
+
 # Download a file
-Notify user agent download a file rather than display its content.
+Notify user agent download a file rather than displaying its content,
+by outputting `Content-Disposition` header.
 ```
 GET <path/to/file>?download
+GET <path/to/file>?downloadfile
 ```
 
 Example:

doc/zh-CN/api.md

@@ -39,6 +39,7 @@ curl 'http://localhost/ghfs/?json'
 # 显示用于下载的页面
 ```
 GET <path>?download[&sort=key]
+GET <path>?downloadfile[&sort=key]
 ```
 类似于常规显示的页面，但隐藏路径列表、可排序的表头和上级目录链接。
 这为“wget”之类的工具递归下载提供了方便。
@@ -48,10 +49,13 @@ GET <path>?download[&sort=key]
 wget --recursive -nc -nH -np 'http://localhost/dir/?download'
 ```
 
+选项`downloadfile`使文件链接可被下载，而不是显示其内容。
+
 # 下载文件
-通知用户代理下载文件而不是显示其内容。
+通过输出`Content-Disposition`头，通知用户代理下载文件而不是显示其内容。
 ```
 GET <path/to/file>?download
+GET <path/to/file>?downloadfile
 ```
 
 举例：

src/serverHandler/pathContext.go

@@ -1,17 +1,21 @@
 package serverHandler
 
 type pathContext struct {
-	download    bool
-	sort        *string // keep different for param is not specified or is empty
-	defaultSort string
+	download     bool
+	downloadfile bool
+	sort         *string // keep different for param is not specified or is empty
+	defaultSort  string
 }
 
 func (ctx pathContext) QueryString() string {
-	// ?download&sort=x/
-	buffer := make([]byte, 1, 18)
+	// ?downloadfile&sort=x/&
+	buffer := make([]byte, 1, 22)
 	buffer[0] = '?'
 
-	if ctx.download {
+	switch {
+	case ctx.downloadfile:
+		buffer = append(buffer, []byte("downloadfile&")...) // 13 bytes
+	case ctx.download:
 		buffer = append(buffer, []byte("download&")...) // 9 bytes
 	}
 
@@ -26,8 +30,8 @@ func (ctx pathContext) QueryString() string {
 }
 
 func (ctx pathContext) FileQueryString() string {
-	if ctx.download {
-		return "?download"
+	if ctx.downloadfile {
+		return "?downloadfile"
 	}
 
 	return ""

src/serverHandler/responseData.go

@@ -38,12 +38,13 @@ type responseData struct {
 
 	Headers [][2]string
 
-	IsDownload bool
-	IsUpload   bool
-	IsMkdir    bool
-	IsDelete   bool
-	IsMutate   bool
-	WantJson   bool
+	IsDownload     bool
+	IsDownloadFile bool
+	IsUpload       bool
+	IsMkdir        bool
+	IsDelete       bool
+	IsMutate       bool
+	WantJson       bool
 
 	CanUpload    bool
 	CanMkdir     bool
@@ -322,11 +323,15 @@ func (h *aliasHandler) getResponseData(r *http.Request) (data *responseData, fsP
 
 	rawQuery := r.URL.RawQuery
 	isDownload := false
+	isDownloadFile := false
 	isUpload := false
 	isMkdir := false
 	isDelete := false
 	isMutate := false
 	switch {
+	case strings.HasPrefix(rawQuery, "downloadfile"):
+		isDownload = true
+		isDownloadFile = true
 	case strings.HasPrefix(rawQuery, "download"):
 		isDownload = true
 	case strings.HasPrefix(rawQuery, "upload") && r.Method == http.MethodPost:
@@ -420,9 +425,10 @@ func (h *aliasHandler) getResponseData(r *http.Request) (data *responseData, fsP
 	canCors := h.getCanCors(rawReqPath, reqFsPath)
 
 	context := pathContext{
-		download:    isDownload,
-		sort:        rawSortBy,
-		defaultSort: h.defaultSort,
+		download:     isDownload,
+		downloadfile: isDownloadFile,
+		sort:         rawSortBy,
+		defaultSort:  h.defaultSort,
 	}
 
 	return &responseData{
@@ -439,12 +445,13 @@ func (h *aliasHandler) getResponseData(r *http.Request) (data *responseData, fsP
 
 		Headers: headers,
 
-		IsDownload: isDownload,
-		IsUpload:   isUpload,
-		IsMkdir:    isMkdir,
-		IsDelete:   isDelete,
-		IsMutate:   isMutate,
-		WantJson:   wantJson,
+		IsDownload:     isDownload,
+		IsDownloadFile: isDownloadFile,
+		IsUpload:       isUpload,
+		IsMkdir:        isMkdir,
+		IsDelete:       isDelete,
+		IsMutate:       isMutate,
+		WantJson:       wantJson,
 
 		CanUpload:    canUpload,
 		CanMkdir:     canMkdir,

src/tpl/frontend/index.html

@@ -96,7 +96,7 @@
 {{end}}
 {{end}}
 <ul class="item-list{{if .HasDeletable}} has-deletable{{end}}">
-	{{if not .IsDownload}}
+	{{if not $isDownload}}
 	<li class="header">{{$dirSort := .SortState.DirSort}}{{$sortKey := .SortState.Key}}
 		<span class="detail">
 		<a class="field dir" href="{{.SubItemPrefix}}{{.Context.QueryStringOfSort .SortState.NextDirSort}}">{{.Trans.ListDirLabel}}{{if eq $dirSort -1}}&uarr;{{else if eq $dirSort 1}}&darr;{{end}}</a>