kubernetes-ingress-controller: Basic authentication doesn't work on KONG in kubernetes cluster

Summary

We use KONG in our kubernetes cluster and deploy it with help of helm. We need to use basic authentication on our prometheus ingress resource. Kong controller deployed in dev2 namespace, prometheus deployed in monitoring namespace.

Kong Ingress controller version kong-docker-kubernetes-ingress-controller.bintray.io/kong-ingress-controller:0.9.1

Kong or Kong Enterprise version kong-docker-kong-enterprise-edition-docker.bintray.io/kong-enterprise-edition:2.1.0.0-beta1-alpine

Kubernetes version

1.15.6 Client Version: version.Info{Major:“1”, Minor:“15”, GitVersion:“v1.15.11”, GitCommit:“d94a81c724ea8e1ccc9002d89b7fe81d58f89ede”, GitTreeState:“clean”, BuildDate:“2020-03-13T17:40:34Z”, GoVersion:“go1.12.17”, Compiler:“gc”, Platform:“linux/amd64”} Server Version: version.Info{Major:“1”, Minor:“15”, GitVersion:“v1.15.11”, GitCommit:“d94a81c724ea8e1ccc9002d89b7fe81d58f89ede”, GitTreeState:“clean”, BuildDate:“2020-03-13T17:40:34Z”, GoVersion:“go1.12.17”, Compiler:“gc”, Platform:“linux/amd64”}

Environment

• Kubernetes cluster based on Azure AKS:
• OS (“Ubuntu 18.04.4 LTS”):
• Kernel Linux k8s-master-13666935-0 5.3.0-1034-azure #35~18.04.1-Ubuntu SMP Mon Jul 13 12:54:45 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

What happened

We have ingress resource:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    cert-manager.io/issuer: letsencrypt-prod
    konghq.com/plugins: basic-auth
    kubernetes.io/ingress.class: kong-dev2
  generation: 1
  labels:
    app: prometheus-operator-prometheus
    app.kubernetes.io/managed-by: Helm
    chart: prometheus-operator-7.4.0
    heritage: Helm
    release: prometheus-operator
  name: prometheus-operator-prometheus
  namespace: monitoring
spec:
  rules:
  - host: example.com
    http:
      paths:
      - backend:
          serviceName: prometheus-operator-prometheus
          servicePort: 9090
        path: /prometheus/
  tls:
  - hosts:
    - example.com
    secretName: letsencrypt-secret
status:
  loadBalancer:
    ingress:
    - ip: 0.0.0.0

And resources needed for basic authentication:

echo "
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: basic-auth
  namespace: monitoring
consumerRef: basic-auth
config:
  hide_credentials: true
plugin: basic-auth
" | kubectl create -f -

echo "
apiVersion: configuration.konghq.com/v1
kind: KongConsumer
metadata:
  name: basic-auth
  namespace: monitoring
username: user
credentials:
- prometheus-secret
" | kubectl create -f -

echo '
apiVersion: v1
kind: Secret
metadata:
  name: prometheus-secret
  namespace: monitoring
stringData:
  kongCredType: basic-auth
  username: user
data:
  password: pass' | kubectl create -f -`

Also I tried to use old way without secret and without section “credentials:” in “KongConsumer”, using:

echo "
apiVersion: configuration.konghq.com/v1
kind: KongCredential
metadata:
  name: basic-auth
  namespace: dev2
consumerRef: basic-auth
type: basic-auth
config:
  username: user
  password: pass
" | kubectl create -f -

but result was the same. I have an error after login, using username “user” and password “pass” - {“message”:“Invalid authentication credentials”}

Expected behavior

Login using username “user” and password “pass”