what is the difference between ngx.header and ngx.resp.add_header?

hrpenf · 2016-05-05T15:36:19+00:00

You may also want to look at storing these as lua module members (see https://github.com/openresty/lua-nginx-module#data-sharing-within-an-nginx-worker)...

what is the difference between ngx.header and ngx.resp.add_header?

hrpenf

I want to do something for open source, and I found lua-nginx-module. I read the todo list, which contain this "add new API function ngx.resp.add_header to emulate the standard add_header config directive.", but I don't know what is the difference between ngx.header and ngx.resp.add_header?

agentzh

Hello!

On Thu, May 5, 2016 at 12:36 AM, rako9000 wrote:
> I want to do something for open source, and I found lua-nginx-module. I read
> the todo list,  which contain this "add new API function ngx.resp.add_header
> to emulate the standard add_header config directive.",  but I don't know
> what is the difference between ngx.header and ngx.resp.add_header?
>

Writing to ngx.header[name] overrides any existing headers of the same
name while ngx.resp.add_header() leave all the existing headers
intact.

Regards,
-agentzh

hrpenf

Thanks for your reply. But what is the result if some one call ngx.resp.add_header("Content-Type: text/html") twice? Return an duplicated error or just output duplicated headers?

On Sunday, May 8, 2016 at 1:32:17 AM UTC+8, agentzh wrote:

Hello!

On Thu, May 5, 2016 at 12:36 AM, rako9000 wrote:
> I want to do something for open source, and I found lua-nginx-module. I read
> the todo list, which contain this "add new API function ngx.resp.add_header
> to emulate the standard add_header config directive.", but I don't know
> what is the difference between ngx.header and ngx.resp.add_header?
>

Writing to ngx.header[name] overrides any existing headers of the same
name while ngx.resp.add_header() leave all the existing headers
intact.

Regards,
-agentzh

agentzh

Hello!

On Sun, May 8, 2016 at 10:29 PM, rako9000 wrote:
> Thanks for your reply. But what is the result if some one call
> ngx.resp.add_header("Content-Type: text/html") twice? Return an duplicated
> error or just output duplicated headers?
>

Duplicate headers, of course. It does exactly what you mean, no matter what.

Regards,
-agentzh