namespacedNameError on Proxy when attempting to submit a cURL call to it

[Varun-Mehrotra]

Report

The Keda http proxy is unable to find hosts and returns NamespacedName is nil error

Expected Behavior

When the proxy is hit with an appropriate host it should be able to serve traffic without an error

Actual Behavior

When I portforward the http-add-on proxy and hit it with a cURL call, it returns Not Found and the following can be seen on the keda-add-ons-http-interceptor-proxy logs:

RROR    LoggingMiddleware.RoutingMiddleware.StaticHandler    Not Found    {"routingKey": "//myhost.com/", "namespacedNameError": "PANIC=value method k8s.io/apimachinery/pkg/types.NamespacedName.MarshalLog called using nil *NamespacedName pointer", "stream": "<nil>"}
github.com/kedacore/http-add-on/interceptor/handler.(*Static).ServeHTTP
    github.com/kedacore/http-add-on/interceptor/handler/static.go:36
github.com/kedacore/http-add-on/interceptor/middleware.(*Routing).ServeHTTP
    github.com/kedacore/http-add-on/interceptor/middleware/routing.go:49
github.com/kedacore/http-add-on/interceptor/middleware.(*Logging).ServeHTTP
    github.com/kedacore/http-add-on/interceptor/middleware/logging.go:42
github.com/kedacore/http-add-on/interceptor/middleware.(*Metrics).ServeHTTP
    github.com/kedacore/http-add-on/interceptor/middleware/metrics.go:24
net/http.serverHandler.ServeHTTP
    net/http/server.go:3137
net/http.(*conn).serve
    net/http/server.go:2039

Steps to Reproduce the Problem

1. Attempt to deploy the example helm chart
2. Port forward the proxy to 8080:8080 as the walkthrough suggests with kubectl port-forward svc/keda-add-ons-http-interceptor-proxy -n keda 8080:8080
3. Run the following cURL call: curl -H "Host:myhost.com" 127.0.0.1:8080

Logs from KEDA HTTP operator

N/A, no relevant HTTP operator logs

HTTP Add-on Version

0.8.0

Kubernetes Version

1.28

Platform

Amazon Web Services

Anything else?

Keda is installed in the keda namespace along with the http-add-on:

[Varun-Mehrotra]

Nevermind, this wasn't the case. Not sure what the specific issues was here but I've got a good feeling I just made a spelling mistake somewhere and when I re-applied things they fixed themselves. Regardless I spent some time going down a rabbit hole. Couple of learnings for anybody who might stumble on this:

1. DNS may have trouble resolving for the externalName service, always try out the FQDN (i.e. keda-add-ons-http-interceptor-proxy.keda.svc.cluster.local) before trying much else.
2. You may have to define ports in the externalName service as well:

apiVersion: v1
kind: Service
metadata:
  name: my-proxy
spec:
  type: ExternalName
  externalName: keda-add-ons-http-interceptor-proxy.keda.svc.cluster.local
  ports:
  - port: 80
    targetPort: 8080

3. The ALB Ingress Controller does not play nice with the externalName service as of now either, but there is an open PR as of writing this. To get around it, I unfortunately just have to run keda and the http add on in each of my namespaces.

[SevginGalibov]

Same problem nginx ingress;

So let me summarize the topic.

http add ons and keda operator are installed in the "keda" namespace. The service list is as follows;

keda-add-ons-http-controller-manager-metrics-service   ClusterIP   x.x.x.x  	<none>        8443/TCP           2d8h
keda-add-ons-http-external-scaler                      ClusterIP   x.x.x.x      <none>        9090/TCP           2d8h
keda-add-ons-http-interceptor-admin                    ClusterIP   x.x.x.x     	<none>        9090/TCP           2d8h
keda-add-ons-http-interceptor-proxy                    ClusterIP   x.x.x.x    	<none>        8080/TCP           2d8h
keda-admission-webhooks                                ClusterIP   x.x.x.x    	<none>        443/TCP            2d9h
keda-interceptor-proxy                                 ClusterIP   x.x.x.x   	<none>        8080/TCP           2d8h
keda-operator                                          ClusterIP   x.x.x.x  	<none>        9666/TCP           2d9h
keda-operator-metrics-apiserver

I have an external API service in the "test" namespace and an externalname service for the keda interceptor.

api-service                   ClusterIP      x.x.x.x  <none>                                                       		  80/TCP    2d8h
keda-interceptor-proxy-test   ExternalName   <none>          keda-add-ons-http-interceptor-proxy.keda.svc.cluster.local   80/TCP    2d8h

The content of my external service in the "test" namespace is as follows;

  externalName: keda-add-ons-http-interceptor-proxy.keda.svc.cluster.local
  ports:
  - port: 80
    protocol: TCP
    targetPort: 8080
  sessionAffinity: None
  type: ExternalName
status:
  loadBalancer: {}

I also have an nginx ingress for my api-service in the "test" namespace;

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
  generation: 6
  name: api-ingress
  namespace: test
spec:
  ingressClassName: nginx
  rules:
  - host: www.api.com
    http:
      paths:
      - backend:
          service:
            name: keda-interceptor-proxy-test
            port:
              number: 80
        path: /
        pathType: Prefix
status:
  loadBalancer:
    ingress:
    - hostname: x.x.x.x

keda-add-ons-http-interceptor logs;

2025-02-09T22:21:04Z	ERROR	LoggingMiddleware.RoutingMiddleware.StaticHandler	Not Found	{"routingKey": "//www.api.com/weatherforecast/", "namespacedNameError": "PANIC=value method k8s.io/apimachinery/pkg/types.NamespacedName.MarshalLog called using nil *NamespacedName pointer", "stream": "<nil>"}
github.com/kedacore/http-add-on/interceptor/handler.(*Static).ServeHTTP
	github.com/kedacore/http-add-on/interceptor/handler/static.go:36
github.com/kedacore/http-add-on/interceptor/middleware.(*Routing).ServeHTTP
	github.com/kedacore/http-add-on/interceptor/middleware/routing.go:54
github.com/kedacore/http-add-on/interceptor/middleware.(*Logging).ServeHTTP
	github.com/kedacore/http-add-on/interceptor/middleware/logging.go:42
github.com/kedacore/http-add-on/interceptor/middleware.(*Metrics).ServeHTTP
	github.com/kedacore/http-add-on/interceptor/middleware/metrics.go:24
net/http.serverHandler.ServeHTTP
	net/http/server.go:3210
net/http.(*conn).serve
	net/http/server.go:2092

When I send the request I get a not found warning on a black page.

What is the problem in this case?