Adapt the nginx.org/rewrites from the official nginxinc helm chart

[philipp-durrer-jarowa]

We have a need to use per-service rewrites like the Nginx Inc. maintained helm chart supports (see https://github.com/nginxinc/kubernetes-ingress/tree/main/examples/ingress-resources/rewrites) however we wouldn't like to switch over to that chart as all our clusters use this chart here, so it would be great if one could adopt the same feature in a nginx.ingress.kubernetes.io/rewrites annotation.

I haven't found any other issues talking about the same feature.

No specific Kubernetes version needed for this feature.

[k8s-ci-robot]

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[longwuyuan]

And you are already using this https://kubernetes.github.io/ingress-nginx/examples/rewrite/ ?

[philipp-durrer-jarowa]

Yes but we'd like to have only one ingress resource per domain, but there are multiple services behind it that need different rewrites. Example:

...
    - host: "{{ $tenant }}.{{ .host }}"
      http:
        paths:
          - path: "/"
            pathType: Prefix
            backend:
              service:
                name: {{ $fullName }}-frontend
                port:
                  name: http-fe
          - path: "/api/"     ---> needs a rewrite to /
            pathType: Prefix
            backend:
              service:
                name: {{ $fullName }}-backend
                port:
                  name: http
          - path: "/static"     ---> needs a rewrite to /$tenant/static/
            pathType: Prefix
            backend:
              service:
                name: {{ $fullName }}-data
                port:
                  name: http-fe
...

With the nginx.org/rewrites I could do this:

    nginx.org/rewrites: "serviceName={{ $fullName }}-backend rewrite=/; serviceName={{ $fullName }}-data rewrite=/{{ $tenant }}/static;"

[longwuyuan]

Thanks for clarifying.

[strongjz]

/assign @Gacko

I will leave this up to @Gacko, but this would be a breaking change for all other uses. The two projects are different, so annotations should reflect that.

[Gacko]

Hm, I think we're mixing up things a bit here.

What @philipp-durrer-jarowa asks for is the ability to have just one Ingress resource per domain (IIRC we are kind of enforcing that somewhere during validations anyway) with different backends separated by path.

In their use case each of those backends requires its own rewrite configuration. Some example requests:

http://first-tenant.great-service.com/anything -> http://frontend-service/anything
http://first-tenant.great-service.com/api/anything -> http://service-backend/anything
http://first-tenant.great-service.com/static/anything -> http://data-backend/first-tenant/anything

If that's correct, I do not think it's related to the chart but more to how we're rendering rewrites in locations.

[longwuyuan]

It seems like this controller's one annotation will perform a single rewrite of the target-path to all rules in that ingress.

But what is @philipp-durrer-jarowa is asking is a combo like ;

• one annotation
• multiple rewrite operations defined in the value part of that one single annotation (new ability)

And @Gacko's example is showing a 2nd new ability of even having option to pick different backends for different rewrite operations, all in the same annotation

[Gacko]

And @Gacko's example is showing a 2nd new ability of even having option to pick different backends for different rewrite operations, all in the same annotation

That is already covered by the rules matching the according paths.

What's not yet covered is the ability to specify a rewrite rule per backend. So in case a requests gets sent to backend A, apply rewrite rule A, if backend b then rewrite rule B and in all the other cases either do nothing or apply a general rewrite rule.

I really don't wanna over-engineer things, but that's how I understand the NGINX Inc. documentation.

[strongjz]

This will be a feature for support in HTTP routes https://gateway-api.sigs.k8s.io/guides/http-redirect-rewrite/

We are working on gateway API support and cannot implement this issue in ingress.

/close

[k8s-ci-robot]

@strongjz: Closing this issue.

In response to this:

This will be a feature for support in HTTP routes https://gateway-api.sigs.k8s.io/guides/http-redirect-rewrite/

We are working on gateway API support and cannot implement this issue in ingress.

/close

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