the http output chain is empty bug (nginx-lua-module)

kirimedia · 2014-06-05T06:55:35+00:00

Bug them about it on the forums http://forum.nginx.org/On Wednesday, June 4, 2014 2:57:57 PM UTC+2, Михаил Ки...

the http output chain is empty bug (nginx-lua-module)

kirimedia

nginx >= 1.5.7
lua module >= 0.9.8 (possibly older version)

# ./sbin/nginx -V
nginx version: nginx/1.5.7
built by gcc 4.4.7 20120313 (Red Hat 4.4.7-3) (GCC)
configure arguments: --add-module=../lua-nginx-module

Config file

user nginx;
worker_processes 1;

error_log /var/log/nginx/nginx-error.log error;

events {
  use epoll;
}

http {
  gzip on;

  server {
    listen 80;
    root /usr/local/nginx/html;

    location = /empty/ {
      empty_gif;
    }

    location = /include/ {
      content_by_lua '
        ngx.location.capture("/empty/")
        ngx.location.capture("/empty/")
      ';
    }

    location = /ssi.html {
      ssi on;
    }
  }
}

Content of /usr/local/nginx/html/ssi.html

HEADER
<!--#include virtual="/include/" wait="yes" -->

On request http://localhost/ssi.html (with header Accept-Encoding: gzip) get a blank response (without headers and no body)

And in the log

[alert] 20457 # 0 : * 1 the http output chain is empty, client: 127.0.0.1, server:, request: "GET / ssi.html HTTP/1.1", subrequest: "/ include /"

How can I fix it?

PS: Sorry for my English.

agentzh

Hello!

On Wed, Jun 4, 2014 at 1:16 AM,  kirimedia wrote:
>     location = /include/ {
>       content_by_lua '
>         ngx.location.capture("/empty/")
>         ngx.location.capture("/empty/")
>       ';
>     }
>
>     location = /ssi.html {
>       ssi on;
>     }
>   }
> }
>
> Content of /usr/local/nginx/html/ssi.html
> HEADER
> <!--#include virtual="/include/" wait="yes" -->
>

Do not mix ngx_lua's subrequests with SSI's subrequests in a single
main request! It just won't work because ngx_lua uses an adjusted
(enhanced) subrequest model that is incompatible with nginx's standard
subrequests. So do not mix them in a single main request otherwise SSI
will get confused and do bad things.

This is actually documented:
https://github.com/openresty/lua-nginx-module#mixing-with-ssi-not-supported

It is recommended to replace your SSI templates with proper Lua-land
templates, which is more flexible and often more efficient than SSI
(keep in mind that ngx_ssi works on the output filter level).

BTW, please do not send the same post multiple times to the list; it
is annoying.

Regards,
-agentzh

brian

> BTW, please do not send the same post multiple times to the list; it is annoying.

This may be my fault. I've been lax in approving/rejecting suspected spam posts - I try to do it once a day, but skipped a couple of days.