Kubernetes

Webhook Relay can help you receive webhooks in your internal services. To achieve that you can use:

  1. Webhook Relay operator - recommended way to forward webhooks to Kubernetes clusters. Handles agent deployment and routing configuration.
  2. A sidecar container - does not automatically configure routing.
  3. A standalone deployment - does not automatically configure routing.
  4. Webhook Relay ingress controller - recommended way to open bidirectional tunnels to expose services directly from your Kubernetes cluster such as Grafana, Prometheus, etc.

Since container is stateless and only requires your access key & secret, deploying and running it is extremely easy. Recommended way to deploy Webhook Relay into your cluster is using the official operator.

Webhook Relay operator not only deploys and manages agent containers that subscribe and forward webhooks but it also configures buckets, inputs (your public endpoints) and outputs (forwarding destinations).

Install

Prerequisites:

You need to add this Chart repo to Helm:

helm repo add webhookrelay https://charts.webhookrelay.com
helm repo update

Get access token from here. Once you click on ‘Create Token’, it will generate it and show a helper to set environment variables:

export RELAY_KEY=*****-****-****-****-*********
export RELAY_SECRET=**********

Install through Helm:

helm upgrade --install webhookrelay-operator --namespace=default webhookrelay/webhookrelay-operator \
  --set credentials.key=$RELAY_KEY --set credentials.secret=$RELAY_SECRET

Usage

Once the operator is deployed, to start receiving webhooks you will need to create a Custom Resource (usually called just ‘CR’). It’s a short yaml file that describes your public endpoint characteristics and specifies where to forward the webhooks:

# cr.yaml
apiVersion: forward.webhookrelay.com/v1
kind: WebhookRelayForward
metadata:
  name: example-forward
spec:
  buckets:
  - name: k8s-operator
    inputs:
    - name: public-endpoint
      description: "Public endpoint, supply this to the webhook producer"
      responseBody: "OK"
      responseStatusCode: 200
    outputs:
    - name: webhook-receiver
      destination: http://destination:5050/webhooks
kubectl apply -f cr.yaml

Uninstall

To remove the agent that is forwarding the webhooks, remove the CR that created it:

kubectl delete -f cr.yaml

To remove operator, use standard Helm command to uninstall the operator.

helm uninstall webhookrelay-operator

Option 2: Sidecar

First, go to https://my.webhookrelay.com/tokens and create a token key & secret pair. Then, create a Kubernetes secret:

kubectl create secret generic webhookrelay-credentials --from-literal=key=[access key] --from-literal=secret=[access secret]

Once the secret is created, you can deploy webhookrelayd container either as a sidecar or a standalone container. Webhookrelayd agent can be easily deployed as a sidecar. This way requests can be forwarded to the service through localhost:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webhookrelay-deployment
  labels:
    app: webhookrelay
spec:
  replicas: 1
  selector:
    matchLabels:
      app: webhookrelay
  template:
    metadata:
      labels:
        app: webhookrelay
    spec:
      containers:
      - name: demo
        image: karolisr/webhook-demo:0.0.15                
        command: ["/bin/webhook-demo"]
        ports:
          - containerPort: 8090          
      # Webhook Relay sidecar
      - name: webhookrelayd
        image: webhookrelay/webhookrelayd:latest
        env:                         
        - name: KEY
          valueFrom:
            secretKeyRef:
              name: webhookrelay-credentials
              key: key                
        - name: SECRET
          valueFrom:
            secretKeyRef:
              name: webhookrelay-credentials
              key: secret
        - name: BUCKETS
          value: bucket1,bucket2,bucket3

Option 3: Separate deployment

Webhook Relay container can also work as standalone deployment:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webhookrelay-deployment
  labels:
    app: webhookrelay
spec:
  replicas: 1
  selector:
    matchLabels:
      app: webhookrelay
  template:
    metadata:
      labels:
        app: webhookrelay
    spec:
      containers:      
      - name: webhookrelayd
        image: webhookrelay/webhookrelayd:latest
        env:                         
        - name: KEY
          valueFrom:
            secretKeyRef:
              name: webhookrelay-credentials
              key: key                
        - name: SECRET
          valueFrom:
            secretKeyRef:
              name: webhookrelay-credentials
              key: secret
        - name: BUCKETS
          value: bucket1,bucket2,bucket3

If agent is deployed as a separate deployment, the output destination should then be a service name.
Repository can be found here: https://github.com/webhookrelay/webhook-demo.

Option 4: Ingress Controller

Implements a Kubernetes ingress controller using tunnels to connect a Web Relay managed URL (https://yoursubdomain.webrelay.io) to a Kubernetes service based on ingress resources. Single ingress controller can manage multiple tunnels and route to multiple namespaces.

Deployment files and issue tracker is available on GitHub:

https://github.com/webrelay/ingress

You can try out Web Relay ingress controller by creating a deployment from a hosted manifest, no clone or local install necessary.

What you do need:

  • A Kubernetes cluster that has access to the Internet
  • kubectl configured with admin access to your cluster
  • relay CLI, installation instructions can be found here

Installing

To add Web Relay ingress controller to your cluster, run:

relay ingress init

Manifests are available here: https://github.com/webrelay/ingress/tree/master/deployment

This command:

  • Creates webrelay-ingress namespace
  • Creates webrelay service account
  • Creates deployment with the controller
  • Creates cluster role and binding
  • Generates access key and secret for the Web Relay server and supplies them as a Kubernetes secret

If RBAC isn’t enabled on your cluster (for example, if you’re on GKE with legacy authorization or Minikube without RBAC), run:

relay ingress init --no-rbac

You can also generate tokens through the Web UI here https://my.webhookrelay.com/tokens or relay token create command on the CLI.

Uninstalling Ingress Controller

To remove it, either delete the namespace where it was deployed or use:

relay ingress reset