Need to support regex extracting in hostname.

[sanigo]

If the hostname support regex, we could use keywords extracted from hostname in rewriting rules. Like the following config:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/use-regex: 'true'
    nginx.ingress.kubernetes.io/rewrite-target: '/repository/$repo/$1 last'
    nginx.ingress.kubernetes.io/proxy-body-size: 8192m
  name: sonatype-nexus-docker
spec:
  rules:
  - host: '~^(?<repo>[^.]+)\.r\.mydomain1\.com$'
    http:
      paths:
      - backend:
          serviceName: sonatype-nexus
          servicePort: 8081
        path: '/(.*)$'
  tls:
  - hosts:
    - '*~^(?<repo>[^.]+)\.r\.mydomain1\.com$'
    secretName: r-mydomain1-cert

Then, docker-releases.r.mydomain1.com will be used as a docker registry url.

[aledbf]

Closing. This is not supported in the Ingress Spec defined in Kubernetes.

[sanigo]

I have found a workaround for this:

    nginx.ingress.kubernetes.io/configuration-snippet: |
      location ~ ^/v2/ {
        set_by_lua_block $repo {
          local host = ngx.req.get_headers()["host"];
          local reg = "^(?<repo>[^.]+).*";
          local m = ngx.re.match(host, reg);
          return m['repo'];
        }
        rewrite ^/(.*)$ /repository/$repo/$1 last;
      }

[awoimbee]

_by_lua_block is now blocked by default for security reasons.
IMO a better way to achieve this is by using server-alias:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/server-alias: ~^([^.]+).my-domain.co
    nginx.ingress.kubernetes.io/server-snippet: set $subdomain $1;
    nginx.ingress.kubernetes.io/permanent-redirect: https://my-domain.co/?subdomain=$subdomain
spec:
  ingressClassName: nginx-public
  rules:
    - host: unique-dummy-url-for-redirect-xyz123.example.com

This is not supported in the Ingress Spec defined in Kubernetes.

Nothing prevents ingress-nginx from extending that spec.