Rails 使用 send_file 发送 0 字节文件 [英] Rails sends 0 byte files using send_file
问题描述
我无法让 send_file(Model.attachment.path) 工作.它没有失败，而是向客户端发送一个 0 字节大小的文件，但文件名是正确的.
I can't get send_file(Model.attachment.path) to work. It doesn't fail, instead, it sends a 0 byte size file to the client, the file names are correct though.
这个问题是在我从 Rails 2.3.8 大迁移到 3 之后开始发生的.
This problem started happening after I did a big migration from Rails 2.3.8 to 3.
在这次迁移中还发生了很多其他事情，我会尽力详细说明所有这些.
There were a lot of other things that took place in this migration and I will try my best to detail all of them.
- 分销变更/服务器变更.Rackspace RHEL5 到 Linode Ubuntu 10.04LTS
- Ruby 版本更改，1.8.6 -> 1.9.2
- Rails 版本更改，2.3.8 -> 3.0.0
- httpd 平台更改，apache2 -> nginx(不过我也尝试过 apache2，但没有奏效).
我通过 ftp 移动了附件，因为它们不是我的 git 存储库的一部分，所以它们通过 cap deploy 发布，而不是手动 ftp 远程(RHEL5)到本地(Win7)然后本地(Win7)到远程(Ubuntu10).
I moved the attachments via ftp as they were not part of my git repositories so they were published via cap deploy, instead manual ftp remote(RHEL5) to local(Win7) then local(Win7) to remote(Ubuntu10).
我确实知道 FTPing 不会通过传输保留文件权限，所以我还模仿了我以前服务器上看到的 chmod，因此它们几乎相同.(用户/组不同，设置为 root:root 而不是 olduser:olduser).
I do know that FTPing does not retain the file permissions through the transfers, so what I've also done is mimicked the chmods that were seen on my previous servers so they are almost identical. (users/groups are different, set to root:root instead of olduser:olduser).
从我的生产日志中下载附件的请求片段.
A snippet of the request to download a attachment from my production log.
Started GET "/attachments/replies/1410?1277105698" for 218.102.140.205 at 2010-09-16 09:44:31 +0000
Processing by AttachmentsController#replies as HTML
Parameters: {"1277105698"=>nil, "id"=>"1410"}
Sent file /srv/app/releases/20100916094249/attachments/replies/UE0003-Requisition_For_Compensation_Leave.doc (0.2ms)
Completed 200 OK in 78ms
一切正常.让我也排除本地问题，我尝试在 Win7 和 Ubuntu(在 Vbox 上)上通过 Chrome 下载.
Everything's okay. Let me also rule out local issues, I've tried downloading via Chrome on both Win7 and Ubuntu (on Vbox).
我还要向您保证，路径确实是正确的.
Let me also assure you that the path is indeed correct.
root@li162-41:/srv/app/current# tail /srv/app/releases/20100916094249/attachments/replies/UE0003-Requisition_For_Compensation_Leave.doc
#
#
%17nw
HQ��+1ae����
%33333333333(��QR���HX�"%%��@9
��@�p4��#P@��Unknown������������G��z �Times New Roman5��Symbol3&�
�z �Arial5&�
所以总结一下这个问题，我如何让 send_file 实际发送文件而不是假的 0 字节垃圾.
So to sum up the question, how do I get send_file to actually send files instead of fake 0 byte junk.
推荐答案
send_file 有 :x_sendfile 参数，在 Rails 3 中默认为 true.此功能通过返回带有路径的 X-Sendfile 标头的空响应，将流式下载卸载到前端服务器 - Apache(使用 mod_xsendfile)或 lighttpd.
send_file has :x_sendfile param which defaults to true in Rails 3.
This feature offloads streaming download to front server - Apache (with mod_xsendfile) or lighttpd, by returning empty response with X-Sendfile header with path.
Nginx 使用 X-Accel-Redirect 标头来实现相同的功能，但您必须在适当的环境文件中正确配置 Rails:
Nginx uses X-Accel-Redirect header for same functionality but you have to
configure Rails properly in proper environment file:
config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect'
Rails 3 更新:此行已存在于 production.rb 中，只需取消注释即可.
Rails 3 update: this line already exists in production.rb, just uncomment it.
将 sendfile on; 添加到您的 nginx 配置以利用 Rails 发送的标头.记住必须使用绝对路径并且nginx必须有文件的读权限.
Add sendfile on; to your nginx config to utilize header sent by Rails.
Remember the absolute path must be used and nginx must have read access to file.
别名文件的另一种方法:
为了更好的安全性，我在 nginx 中使用别名而不是绝对路径，但是 send_file 方法会检查是否存在以别名失败的文件.因此，我将我的操作更改为:
For better security I use aliases in nginx instead of absolute paths,
however send_file method checks existence of file which fails with alias.
Thus I changed my action to:
head(
'X-Accel-Redirect'=> file_item.location,
'Content-Type' => file_item.content_type,
'Content-Disposition' => "attachment; filename="#{file_item.name}"");
render :nothing => true;
这篇关于Rails 使用 send_file 发送 0 字节文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
