Here is my use case: We have a customer, where each of their services has to be available on dedicated subdomain. Naming convention should be service-name.customerdomain.com, where service-name is the deployed service and customerdomain.com is the customer domain. When a new service is created, it should be available automatically, i.e. once service-name service is deployed into the cluster, it has to be available on service-name.customerdomain.com.

I know, this can be achieved manually by following steps:

1. Add Ingress controller to the cluster

2. Create wildcard DNS *.customerdomain.com and point it to the Ingress controller

3. Map subdomain for each running service. For every existing service from the cluster create a separate section into Ingress resource file ingress.yaml, e.g.

Spec:     
    rules: 
    - host: helloworld.awesome-customer.com 
    http: 
        paths: 
        - path: /* 
        backend: 
            serviceName: helloworld 
            servicePort: 8080 
    - host: nextfineapp.awesome-customer.com 
    http: 
        paths: 
        - path: /* 
        backend: 
            serviceName: nextfineapp 
            servicePort: 8080 
    - [...]

4. Add Ingress resource file new -host section for each newly deployed service
5. Remove Ingress resource file -host section for each removed service

Basically - I would like to automate steps 4 & 5. I am aware Ingress cannot handle this by itself, however, googling around, it appears that updating ingress.yaml file each time a new service is deployed / an existing one is removed can be achieved via Helm and its values files.

I would appreciate if a sample solution can be pointed out / described below.