Add a custom header per rule on Kubernetes Ingress with Traefik - kubernetes

Question

I'm moving to kubernetes using traefik as my Ingress Controller.
I have a single backend that should respond to 3000+ websites. Depending on the host, I need to add a custom header to the request before proxy passing it to the backend.
I can use the ingress.kubernetes.io/custom-request-headers annotation to add a custom header to the request but it's an annotation for the whole Ingress, so I would need to create 3000+ Ingresses, one for each website.
Is there another way to do this? Creating 3000+ Ingresses is the same thing as creating one Ingress with 3000+ rules?

Answer 1

Yes, you need to create one Ingress object per one host, if you want different headers her host.
You can do it by Traefik:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: traeffic-custom-request-header
annotations:
ingress.kubernetes.io/custom-request-headers: "mycustomheader: myheadervalue"
spec:
rules:
- host: custom.configuration.com
http:
paths:
- backend:
serviceName: http-svc
servicePort: 80
path: /
Also, the same thing you can do by Nginx Ingress Controller.
It has the support for configuration snipper. Here is an example of using it to set a custom header per Ingress object:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: nginx-configuration-snippet
annotations:
nginx.ingress.kubernetes.io/configuration-snippet: |
more_set_headers "Request-Id: $request_id";
spec:
rules:
- host: custom.configuration.com
http:
paths:
- backend:
serviceName: http-svc
servicePort: 80
path: /
BTW, you can use several different ingress controllers on your cluster, so it does not need to migrate everything to only one type of Ingress.