Allow run time updating of GeoIP databases

[Stono]

Hey,
At the moment, the following GeoIP databases are downloaded as part of the nginx base image build:

  - geoip_country       /etc/nginx/GeoIP.dat;
  - geoip_city          /etc/nginx/GeoLiteCity.dat;
  - geoip_org           /etc/nginx/GeoIPASNum.dat;

These databases get updated (GeoIPASNum more than others), and I think it'd be nice to find a way to update this outside the update cycle of ingress-nginx

I'm unsure however, the best way to do this so didn't want to implement a PR without talking it through first. I see the following options:

1. Add --update-geo-ip, which downloads these files every time the container boots, or if they're over some arbitrary age.
2. Have a separate side car which keeps these files up to date, but that would some how have to trigger an nginx -s reload

I'm totally open to ideas?

[aledbf]

@Stono what we can do is to change the path of the files to a directory like /etc/nginx/geoip and then you can use a custom deployment with an additional container that updates the file and an emptyDir volume mounted in /etc/nginx/geoip

[Stono]

@aledbf that makes sense, but then how would that side car trigger an nginx -s reload when the db changes?

[aledbf]

that makes sense, but then how would that side car trigger an nginx -s reload when the db changes?

I was thinking to just wait until the next event that triggers an update in the controller

[aledbf]

@Stono or run nginx -s reload using kubectl exec from the side car

[Stono]

hmm then i'd have to give the sidecar RBAC access to exec pods on kubectl which feels a bit wrong ;'(

[aledbf]

@Stono ok, then I can add another notify listener for the geoip directory and trigger a reload like here https://github.com/kubernetes/ingress-nginx/blob/master/internal/ingress/controller/nginx.go#L170

[Stono]

Ahh great idea @aledbf - leave it with me and I'll (try) to do a PR!

[Stono]

OK @aledbf - gave it my best shot! See the attached PR

[Niteesh]

can this help, the feature is already provided by geoip2 module, can we exploit that.

http {

    geoip2 /etc/GeoLite2-Country.mmdb {
        **auto_reload 5m;**
        $geoip2_metadata_country_build metadata build_epoch;
        $geoip2_data_country_code default=US source=$http_x_forwarded_for country iso_code;
        $geoip2_data_country_name source=$http_x_forwarded_for country names en;
    }