Provisioning Consumers and Credentials

This guide walks through how to use the KongConsumer custom resource and use Secret resources to associate credentials with those consumers.

Installation

Please follow the deployment documentation to install the Kubernetes Ingress Controller onto your Kubernetes cluster.

Installing the Gateway APIs

If you wish to use the Gateway APIs examples, follow the supplemental Gateway APIs installation instructions.

Testing connectivity to Kong Gateway

This guide assumes that PROXY_IP environment variable is set to contain the IP address or URL pointing to Kong Gateway. If you’ve not done so, follow one of the deployment guides to configure this environment variable.

If everything is setup correctly, making a request to Kong Gateway should return back a HTTP 404 Not Found status code:

curl -i $PROXY_IP

Response:

HTTP/1.1 404 Not Found
Content-Type: application/json; charset=utf-8
Connection: keep-alive
Content-Length: 48
X-Kong-Response-Latency: 0
Server: kong/3.0.0

{"message":"no Route matched with those values"}

This is expected since Kong Gateway doesn’t know how to proxy the request yet.

Deploy an upstream HTTP application

To proxy requests, you need an upstream application to proxy to. Deploying this echo server provides a simple application that returns information about the Pod it’s running in:

echo "
apiVersion: v1
kind: Service
metadata:
  labels:
    app: echo
  name: echo
spec:
  ports:
  - port: 1025
    name: tcp
    protocol: TCP
    targetPort: 1025
  - port: 1026
    name: udp
    protocol: TCP
    targetPort: 1026
  - port: 1027
    name: http
    protocol: TCP
    targetPort: 1027
  selector:
    app: echo
---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: echo
  name: echo
spec:
  replicas: 1
  selector:
    matchLabels:
      app: echo
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: echo
    spec:
      containers:
      - image: kong/go-echo:latest
        name: echo
        ports:
        - containerPort: 1027
        env:
          - name: NODE_NAME
            valueFrom:
              fieldRef:
                fieldPath: spec.nodeName
          - name: POD_NAME
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: POD_NAMESPACE
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
          - name: POD_IP
            valueFrom:
              fieldRef:
                fieldPath: status.podIP
        resources: {}
" | kubectl apply -f -

Response:

service/echo created
deployment.apps/echo created

Create a configuration group

Ingress and Gateway APIs controllers need a configuration that indicates which set of routing configuration they should recognize. This allows multiple controllers to coexist in the same cluster. Before creating individual routes, you need to create a class configuration to associate routes with:

echo "
apiVersion: networking.k8s.io/v1
kind: IngressClass
metadata:
  name: kong
spec:
  controller: ingress-controllers.konghq.com/kong
" | kubectl apply -f -

ingressclass.networking.k8s.io/kong configured

echo "
---
apiVersion: gateway.networking.k8s.io/v1beta1
kind: GatewayClass
metadata:
  name: kong
  annotations:
    konghq.com/gatewayclass-unmanaged: 'true'

spec:
  controllerName: konghq.com/kic-gateway-controller
---
apiVersion: gateway.networking.k8s.io/v1beta1
kind: Gateway
metadata:
  name: kong
spec:
  gatewayClassName: kong
  listeners:
  - name: proxy
    port: 80
    protocol: HTTP
  - name: proxy-ssl
    port: 443
    protocol: HTTPS
" | kubectl apply -f -

gatewayclass.gateway.networking.k8s.io/kong created
gateway.gateway.networking.k8s.io/kong created

kubectl get gateway kong

NAME   CLASS   ADDRESS        READY   AGE
kong   kong    203.0.113.42   True    4m46s

Kubernetes Ingress Controller recognizes the kong IngressClass and konghq.com/kic-gateway-controller GatewayClass by default. Setting the CONTROLLER_INGRESS_CLASS or CONTROLLER_GATEWAY_API_CONTROLLER_NAME environment variable to another value overrides these defaults.

Add routing configuration

Create routing configuration to proxy /echo requests to the echo server:

echo "
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: echo
  annotations:
    konghq.com/strip-path: 'true'
spec:
  ingressClassName: kong
  rules:
  - host: kong.example
    http:
      paths:
      - path: /echo
        pathType: ImplementationSpecific
        backend:
          service:
            name: echo
            port:
              number: 1027
" | kubectl apply -f -

ingress.networking.k8s.io/echo created

echo "
apiVersion: gateway.networking.k8s.io/v1beta1
kind: HTTPRoute
metadata:
  name: echo
  annotations:
    konghq.com/strip-path: 'true'
spec:
  parentRefs:
  - name: kong
  hostnames:
  - 'kong.example'
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /echo
    backendRefs:
    - name: echo
      kind: Service
      port: 1027
" | kubectl apply -f -

httproute.gateway.networking.k8s.io/echo created

Test the routing rule:

curl -i http://kong.example/echo --resolve kong.example:80:$PROXY_IP

Response:

HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8
Content-Length: 140
Connection: keep-alive
Date: Fri, 21 Apr 2023 12:24:55 GMT
X-Kong-Upstream-Latency: 0
X-Kong-Proxy-Latency: 1
Via: kong/3.2.2

Welcome, you are connected to node docker-desktop.
Running on Pod echo-7f87468b8c-tzzv6.
In namespace default.
With IP address 10.1.0.237.
...

If everything is deployed correctly, you should see the above response. This verifies that Kong Gateway can correctly route traffic to an application running inside Kubernetes.

Add authentication to the service

With Kong, adding authentication in front of an API is as simple as enabling a plugin. To enforce authentication requirements on the on the route you’ve created, create a KongPlugin resource with an authentication plugin, such as key-auth:

echo "
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: example-auth
plugin: key-auth
" | kubectl apply -f -

Response:

kongplugin.configuration.konghq.com/example-auth created

Now, associate this plugin with the previous Ingress rule we created using the konghq.com/plugins annotation:

kubectl annotate ingress echo konghq.com/plugins=example-auth

ingress.networking.k8s.io/echo annotated

kubectl annotate httproute echo konghq.com/plugins=example-auth

httproute.gateway.networking.k8s.io/echo annotated

Any request matching the proxying rules defined in the echo routing configuration will now require a valid API key:

curl -si http://kong.example/echo --resolve kong.example:80:$PROXY_IP

Response:

HTTP/1.1 401 Unauthorized
Content-Type: application/json; charset=utf-8
Connection: keep-alive
WWW-Authenticate: Key realm="kong"
Content-Length: 41
Server: kong/3.0.1

{"message":"No API key found in request"}

Requests that do not include a key receive a 401 Unauthorized response.

Provision a consumer and credential

First, create a credential Secret:

kubectl create secret generic kotenok-key-auth \
  --from-literal=kongCredType=key-auth  \
  --from-literal=key=gav

Response:

secret/kotenok-key-auth created

Second, create a KongConsumer resource that uses the Secret:

echo "apiVersion: configuration.konghq.com/v1
kind: KongConsumer
metadata:
  name: kotenok
  annotations:
    kubernetes.io/ingress.class: kong
username: kotenok
credentials:
- kotenok-key-auth
" | kubectl apply -f -

Response:

kongconsumer.configuration.konghq.com/kotenok created

Credential Secrets include a kongCredType key, whose value indicates what authentication plugin the credential is for, and keys corresponding to the fields necessary to configure that credential type (key for key-auth credentials).

Use the credential

Now, send a request including the credential (key-auth expects an apikey header with the key by default):

curl -si http://kong.example/echo --resolve kong.example:80:$PROXY_IP -H "apikey: gav"

Response:

HTTP/1.1 200 OK                
Content-Type: text/plain; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Date: Fri, 09 Dec 2022 22:16:24 GMT
Server: echoserver
x-added-service:  demo
X-Kong-Upstream-Latency: 0
X-Kong-Proxy-Latency: 1
Via: kong/3.1.1

Hostname: echo-fc6fd95b5-8tn52
...

In this guide, you learned how to leverage an authentication plugin in Kong and provision credentials. This enables you to offload authentication into your Ingress layer and keeps the application logic simple.

All other authentication plugins bundled with Kong work in this way and can be used to quickly add an authentication layer on top of your microservices.