How to install Kong in a specific namespace and route requests to a service using Kubernetes Ingress?

Question

I'm trying to set up Kong as an API gateway in my Kubernetes cluster. I have a service named quick-links-service running in the default namespace, and I want to install Kong in the kong namespace to route requests to this service. Here's the YAML for my Ingress resource:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: quick-links-ingress
  annotations:
    konghq.com/strip-path: 'true'
spec:
  ingressClassName: kong
  rules:
    - host: kong.example
      http:
        paths:
          - path: /quick-links
            pathType: Prefix
            backend:
              service:
                name: quick-links-service
                port:
                  number: 3000

I've tried installing Kong using Helm in the kong namespace with the following command:

helm install kong kong/kong --namespace kong  --set admin.useTLS=false,admin.enabled=true,admin.http.enabled=true

I forwarded port of the kong pod:

kubectl port-forward kong-kong-b7f7889d-mwlf9 -n kong 8001:8001    

When I hit http://localhost:80001/services, I get below response:

{
    "next": null,
    "data": [
        {
            "id": "0061fec8-7d38-5786-aa81-4174caf13e05",
            "enabled": true,
            "write_timeout": 60000,
            "tls_verify": null,
            "name": "default.quick-links-service.3000",
            "retries": 5,
            "path": "/",
            "port": 3000,
            "tags": [
                "k8s-name:quick-links-service",
                "k8s-namespace:default",
                "k8s-kind:Service",
                "k8s-uid:c5065699-bbef-41ba-a495-a6b643021da6",
                "k8s-version:v1"
            ],
            "ca_certificates": null,
            "client_certificate": null,
            "protocol": "http",
            "connect_timeout": 60000,
            "created_at": 1708140855,
            "read_timeout": 60000,
            "tls_verify_depth": null,
            "host": "quick-links-service.default.3000.svc",
            "updated_at": 1708140855
        }
    ]
}

However, I'm having trouble configuring Kong to route requests to the quick-links-service.

How can I properly configure Kong and the Ingress resource to achieve this and access quick-links using kong locally?

Answer 1

When you have more than one ingress controller and Kong is not the default, you should use Kong CRD to specify it's configuration.

Kong ingress controller provides a Custom Resource Definition KongIngress to define Kong specific configuration properties:

apiVersion: configuration.konghq.com/v1
kind: KongIngress
metadata:
  name: quick-links-ingress
  labels:
    quick-links-ingress-selector
route:
  strip_path: true

---

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: quick-links-ingress
  labels:
    quick-links-ingress-selector
spec:
  ingressClassName: kong
  rules:
    - host: kong.example
      http:
        paths:
          - path: /quick-links
            pathType: Prefix
            backend:
              service:
                name: quick-links-service
                port:
                  number: 3000