Error_page can not work in if directive

Server NGINX
1

I want to display different pages when 413 code return, for example

set $var 1;
if （$var = 1) {
error_page 413 /413_old.html;
}
if ($var =2) {
error_page 413 /413_new.html;
}

error_page can not work, but I write error_page directive in location
block
directly instead of using if directive, it can work normally

Posted at Nginx Forum:

2

please help me, thank you

Posted at Nginx Forum:

3

Hello!

On Tue, Dec 25, 2012 at 08:06:45AM -0500, xinghua_hi wrote:

error_page can not work, but I write error_page directive in location block
directly instead of using if directive, it can work normally

There several ways to do what you want. E.g. you may use
variables in the error page specified, e.g.

error_page 413 /413.$var.html;

or use an error_page with additional processing for the page in
question, e.g.

error_page 413 /413.html;

location = /413.html {
if ($new) {
rewrite ^ /413.new.html;
}
}

–
Maxim D.

4

Hello!

On Tue, Dec 25, 2012 at 10:09:45AM -0500, xinghua_hi wrote:

            error_page 413 /413.html;
        }
    }

but

client_max_body_size 50k;
location / {
error_page 413 /413.html;
}
it works!

The 413 error is generated once location configuration is
determinded, and this happens before location-level rewrite module
directives (the “if” directive in particular) are executed. Hence
error_page 413 configure inside the “if” doesn’t make any
difference.

(Please also note that in general it’s a good idea to avoid using
the “if” directive, see http://wiki.nginx.org/IfIsEvil.)

–
Maxim D.

5

thank you very much, but i sitll want to know why error_page can’t work
normally in if block.
I see the error_page 's context can be " if in location" in the
document.

the whole location conf like below, error_page can not work:

client_max_body_size 50k;
location / {
set $var “haha”;
if ($var = “haha”) {
error_page 413 /413.html;
}
}

but

client_max_body_size 50k;
location / {
error_page 413 /413.html;
}
it works!

and

location / {
set $var “haha”;
if ($var = “haha”) {
error_page 404 /404.html;
}
}

it also works!

thanks！

Posted at Nginx Forum:

6

Hello!

On Tue, Dec 25, 2012 at 11:47:58AM -0500, xinghua_hi wrote:

will return 404, but 413.haha.html exists my root dir。I see the debug log ,
find some log like
http finalize request: 404, “/413…html?”
obviously, nginx takes $var as an empty string, I think the reason is also
that 413 error is generated before set directive? so , how to use variable
in error_page uri?

Same problem here: the “set” directive isn’t executed, and hence
the $var isn’t “haha” but uninitialized and evaluates to an empty
string.

You have to make $var variable available by other means (e.g. set
the variable at server level, or make it available via map{}
directive).

 }

}

the key problem is how can i pass the $var to location /413.html? I try
it , the second $var is empty（I also wonder about the result because I
remember when internal redirect, the location can share the variable) 。

And the same problem here: “set $var “haha”;” in the location /
isn’t executed, and hence $var remains uninitialized.

–
Maxim D.

7

thanks, but a new question comming。
I try to resolve my problem according to your method:
(1)
“set" is also an location-level rewrite module directive, so the conf
like
this
location / {
root XXX;
set $var “haha”;
error_page 413 /413.${var}.html;
}

will return 404, but 413.haha.html exists my root dir。I see the debug
log ,
find some log like
http finalize request: 404, “/413…html?”
obviously, nginx takes $var as an empty string, I think the reason is
also
that 413 error is generated before set directive? so , how to use
variable
in error_page uri?

(2)
if I writer conf like this:
location / {
set $var “haha”;
error_page 413 /413.html;
}

location = /413.html {
if ($var) {
rewriter ^ /413.new.html;
}
}

the key problem is how can i pass the $var to location /413.html? I
try
it , the second $var is empty（I also wonder about the result because I
remember when internal redirect, the location can share the variable) 。

Thank you .

Posted at Nginx Forum: