limit_req for spiders only

[Toni Mueller]

Hi,

I would like to put a brake on spiders which are hammering a site with
dynamic content generation. They should still get to see the content,
but only not generate excessive load. I therefore constructed a map to
identify spiders, which works well, and then tried to

limit_req_zone $binary_remote_addr zone=slow:10m ...;

if ($is_spider) {
    limit_req zone=slow;
}


Unfortunately, limit_req is not allowed inside "if", and I don't see an
obvious way to achieve this effect otherwise.

If you have any tips, that would be much appreciated!


Kind regards,
--Toni++