Forum: NGINX Variables and includes

Is it possible to use a variable from one configuration in a included
config file?  Example:

set $a = "hello";
include test.conf;

[test.conf]
if ($a = "hello") {
     set $a = "world";
}
# something that works with $a

Within the scope of the commands of test.conf, will $a be "hello" or
"world"?  Currently my usage like this gives me a, "using unitialized
variable" warning.
--
Daniel

Hello!

On Sat, Jan 12, 2013 at 09:40:14PM -0800, Daniel L. Miller wrote:

> # something that works with $a
>
> Within the scope of the commands of test.conf, will $a be "hello" or
> "world"?  Currently my usage like this gives me a, "using
> unitialized variable" warning.

The "include" directive works during configuration parsing and
completely transparent to everything else.  That is, you may set a
variable in one file and then use it in an included file, it is
expected to work fine.

On the other hand, example you've provided is syntactically
invalid and will result in the following error during
configuration parsing:

nginx: [emerg] invalid number of arguments in "set" directive in ...

Correct way to write it would be

   set $a "hello";

Note there is no "=" character.  See http://nginx.org/r/set for
details.

Note well, that after fixing the example the $a at the end of
test.conf will be either "world" (if test.conf goes after 'set $a
"hello";') or uninitialized if it's included somewhere else.

--
Maxim Dounin
http://nginx.com/support.html

On 1/13/2013 6:50 PM, Maxim Dounin wrote:
>> [test.conf]
> variable in one file and then use it in an included file, it is
>     set $a "hello";
>
> Note there is no "=" character.  See http://nginx.org/r/set for
> details.
Shows what happens when you quickly type up an example...thanks for
catching it.

So I repeat my question - why, given the above example (with correct
syntax), would I see warnings for "uninitialized variable" for the above
in the "test.conf", as the variable is declared prior to the include
statement?

--
Daniel

Hello!

On Sun, Jan 13, 2013 at 08:18:35PM -0800, Daniel L. Miller wrote:

> >>
> >completely transparent to everything else.  That is, you may set a
> >
> include statement?
Because of another problem resulted from quick typing?  Show the
exact configuration which produces warning for you.

--
Maxim Dounin
http://nginx.com/support.html