Condition to match a missing "Host:" header

[Luigi Perroti]

Igor Sysoev <is at ...> writes:

> Why do you need to test it ?
> Have you tried the configuration in my previous mail ?

Yes, I tried what you suggested.
Now I have a better understanding of how nginx works, thank you.

As of now I've come up with a configuration file that works fine for the
application that I'll have to run.

The only thing is that, with this configuration, when no "Host:" header is sent
by the client nginx will handle this with a 400 code directly. The application
won't receive the request. Since this application does access logging by itself
I disabled access logging in nginx.

But I would like to turn it back on for requests where no Host header is
specified. Otherwise I'd have no way to know about these requests.

I also do this when my custom error pages are called directly.

The relevant part of my config file can be found here: http://pastebin.com/mc05d231

Note that although it might be written better this does exactly what I want.
Except for the fact that I can't have nginx log to access.log the requests with
no Host header, and I can't get my application to handle them either.