From 2c75c73886f09843881a1853ba74fdf04d18641a Mon Sep 17 00:00:00 2001
From: HFO4 <912394456@qq.com>
Date: Sat, 14 Dec 2019 15:06:30 +0800
Subject: [PATCH] Modify: preview should use login session to enable http-range

---
 routers/controllers/file.go | 16 +++++++++-------
 routers/router.go           |  4 ++--
 service/explorer/file.go    | 24 +++++++++++++++++++++++-
 3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/routers/controllers/file.go b/routers/controllers/file.go
index 3f6fcd4..79ae686 100644
--- a/routers/controllers/file.go
+++ b/routers/controllers/file.go
@@ -137,20 +137,22 @@ func Thumb(c *gin.Context) {
 
 }
 
-// RedirectToDownload 创建下载会话并重定向至下载地址
-func RedirectToDownload(c *gin.Context) {
+// Preview 预览文件
+func Preview(c *gin.Context) {
 	// 创建上下文
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
 	var service explorer.FileDownloadCreateService
 	if err := c.ShouldBindUri(&service); err == nil {
-		res := service.CreateDownloadSession(ctx, c)
-		if res.Code == 0 {
+		res := service.PreviewContent(ctx, c)
+		// 是否需要重定向
+		if res.Code == -301 {
 			c.Redirect(301, res.Data.(string))
-			return
 		}
-		c.JSON(200, res)
+		if res.Code != 0 {
+			c.JSON(200, res)
+		}
 	} else {
 		c.JSON(200, ErrorResponse(err))
 	}
@@ -171,7 +173,7 @@ func CreateDownloadSession(c *gin.Context) {
 	}
 }
 
-// DownloadArchived 文件下载
+// Download 文件下载
 func Download(c *gin.Context) {
 	// 创建上下文
 	ctx, cancel := context.WithCancel(context.Background())
diff --git a/routers/router.go b/routers/router.go
index 928fa68..ccea9cf 100644
--- a/routers/router.go
+++ b/routers/router.go
@@ -106,8 +106,8 @@ func InitRouter() *gin.Engine {
 				file.POST("upload", controllers.FileUploadStream)
 				// 创建文件下载会话
 				file.PUT("download/*path", controllers.CreateDownloadSession)
-				// 创建文件下载并重定向到下载地址
-				file.GET("redirect/*path", controllers.RedirectToDownload)
+				// 预览文件
+				file.GET("preview/*path", controllers.Preview)
 				// 获取缩略图
 				file.GET("thumb/:id", controllers.Thumb)
 				// 取得文件外链
diff --git a/service/explorer/file.go b/service/explorer/file.go
index a51a6c0..f68654d 100644
--- a/service/explorer/file.go
+++ b/service/explorer/file.go
@@ -112,7 +112,7 @@ func (service *FileDownloadCreateService) CreateDownloadSession(ctx context.Cont
 	}
 }
 
-// Download 文件下载
+// Download 通过签名URL的文件下载，无需登录
 func (service *DownloadService) Download(ctx context.Context, c *gin.Context) serializer.Response {
 	// 创建文件系统
 	fs, err := filesystem.NewFileSystemFromContext(c)
@@ -150,3 +150,25 @@ func (service *DownloadService) Download(ctx context.Context, c *gin.Context) se
 		Code: 0,
 	}
 }
+
+// PreviewContent 预览文件，需要登录会话
+func (service *FileDownloadCreateService) PreviewContent(ctx context.Context, c *gin.Context) serializer.Response {
+	// 创建文件系统
+	fs, err := filesystem.NewFileSystemFromContext(c)
+	if err != nil {
+		return serializer.Err(serializer.CodePolicyNotAllowed, err.Error(), err)
+	}
+
+	// 获取文件流
+	rs, err := fs.GetDownloadContent(ctx, service.Path)
+	if err != nil {
+		return serializer.Err(serializer.CodeNotSet, err.Error(), err)
+	}
+	defer rs.Close()
+
+	http.ServeContent(c.Writer, c.Request, fs.FileTarget[0].Name, fs.FileTarget[0].UpdatedAt, rs)
+
+	return serializer.Response{
+		Code: 0,
+	}
+}