Add nginx retain ip header

[gaoyifan]

If docker container runs behind a reverse proxy (like CDN), unicorn cannot get real client IP, because nginx overrides HTTP header X-Forwarded-For and X-Real-IP.

NGINX_RETAIN_IP_HEADER parameter let nginx retain X-Forwarded-For and X-Real-IP.

[knight42]

ping @sameersbn @solidnerd

[solidnerd]

I will test this feature within a week and will give you feedback after that. I hope it's okay for you.

[knight42]

@solidnerd Any progress?

[lenovouser]

Seems like a good feature to me 👍

[solidnerd]

Should this be done for nginx-ssl as well ? Is it a possible test case ?

[lenovouser]

Yep, should be done for the SSL part too IMO

[knight42]

@solidnerd
nginx_configure_gitlab_retain_ip_header() is called in nginx_configure_gitlab(), which means it directly modify /etc/nginx/sites-enabled/gitlab, hence I think there is no need for this to be done for nginx-ssl.

[phenomax]

Do we have any updates here?
I also agree that this PR adds an useful feature to this docker image.

[dmednis]

When can we expect this to be merged?
This would be a really useful feature.

[gaoyifan]

@dmednis You can try this fork. Maintained by @knight42

[3kami3]

I tried setting GitLabCE official document, so please also try this PR #1137.

[gaoyifan]

Agree with @3kami3 😀. I think the implementation in #1137 is safer. And I will close this one.