Variables: Socket cookie variable for debugging purposes

Donatas Abraitis donatas.abraitis at
Tue Jul 11 20:06:08 UTC 2017

I haven't seen $connection before. Dunno how I missed it.

On Tue, Jul 11, 2017 at 10:58 PM, Maxim Dounin <mdounin at> wrote:
> Hello!
> On Tue, Jul 11, 2017 at 10:18:00PM +0300, Donatas Abraitis wrote:
>> In short, it provides unique socket identifier.
>> * It would be simpler to identify connections and filter them out by
>> $socket_cookie only. As an example could be a custom response header
>> `X-Request: $socket_cookie:$request_id`, or just `X-Socket-Id:
>> $socket_cookie`.
> So how do you expect to use it?  And why you need $socket_cookie
> if there is $request_id and/or $connection?
>> * Another example could be to use some other fancy stuff like load
>> balancing (hashing) by $socket_cookie.
> I see no difference with using $connection, $request_id, or any
> other number.  If you think there is a difference, please
> elaborate.
>> At the moment at we are using $request_id to identify
>> requests for clients, but $socket_cookie would be helpful too.
> Note that $socket_cookie cannot be used to identify requests, it
> can only be used to identify connections.  There may be multiple
> requests in a connection.
> Overral, it is still not clear if proposed variable is beneficial
> and how it is expected to be used.  If you think it is useful,
> consider writing a module which provides the variable.
> --
> Maxim Dounin
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