Monitoring for rejected resources: collisions count

[dmitriy-myz]

Is your feature request related to a problem? Please describe.
I want to have monitoring if I have ingress collisions.
When we have more then one ingress resource with same hostname one of them are rejected..
If ingress controller would provide metric when I can setup alerting based on this.
Describe the solution you'd like
add new metric with number of rejected ingress resources like this

nginx_ingress_controller_ingress_resources_total{class="nginx",type="rejected"} 1
nginx_ingress_controller_ingress_resources_total{class="nginx",type="master"} 0
nginx_ingress_controller_ingress_resources_total{class="nginx",type="minion"} 0
nginx_ingress_controller_ingress_resources_total{class="nginx",type="regular"} 238

Describe alternatives you've considered
As alternative I currently could parse logs of ingress controller or parse events from kuberetes itself.

[github-actions]

Hi @dmitriy-myz thanks for reporting!

Be sure to check out the docs and the Contributing Guidelines while you wait for a human to take a look at this 🙂

Cheers!