Event Channels

Flexible event routing using Apache Camel Kamelets

Event Channels give you a way to route CloudEvents to other systems using Apache Camel Kamelets. Think of them as delivery pipes: they pick up CloudEvents from NATS JetStream and push them out to wherever they need to go.

Configuration Format

Event channels are configured using YAML files:

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: slack-notifications
  description: Send events to Slack channel
spec:
  type: slack
  parameters:
    webhookUrl: "{{slack_webhook}}"
    channel: "#notifications"
  variables:
    - slack_webhook: "{{sys:SLACK_WEBHOOK_URL}}"
  requirements:
    network: "true"

Applying Configuration

Use the Weikio CLI to apply event channel configurations:

weikio config apply filename.yaml

API Endpoints

1. GET /eventchannels/configurations

   • Returns all event channels
   • Requires “EventChannel.Read” policy

2. GET /eventchannels/configurations/{name}

   • Returns a specific event channel by name
   • Requires “EventChannel.Read” policy

Event Channel Types

Event channels are based on Apache Camel Kamelets. You can use any sink Kamelet from the Apache Camel Kamelet catalog.

Slack Channel

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: slack-notifications
  description: Send events to Slack channel
spec:
  type: slack
  parameters:
    webhookUrl: "{{slack_webhook}}"
    channel: "#notifications"
  variables:
    - slack_webhook: "{{sys:SLACK_WEBHOOK_URL}}"
  requirements:
    network: "true"

AWS S3 Channel

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: s3-archive
  description: Archive events to AWS S3 bucket
spec:
  type: aws-s3
  parameters:
    bucketNameOrArn: "events-archive"
    accessKey: "{{aws_access_key}}"
    secretKey: "{{aws_secret_key}}"
    region: "us-east-1"
    autoCreateBucket: "true"
  variables:
    - aws_access_key: "{{sys:AWS_ACCESS_KEY}}"
    - aws_secret_key: "{{sys:AWS_SECRET_KEY}}"
  requirements:
    network: "true"

HTTP Channel

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: webhooksite-http
  description: Send events to Webhooksite
spec:
  type: http
  parameters:
    url: "{{target}}"
    method: "POST"
  variables:
    - target: "{{sys:webhooksite}}"

Event Processing

When an event channel is configured:

1. A NATS JetStream stream is automatically created

   • Stream name: eventchannel-{name}-stream
   • Subject: eventchannel.{name}
   • Republish configuration to eventchannelprocessing.{name}

2. An Integration Flow is created using the specified Kamelet

   • Flow reads CloudEvents from the NATS processing subject
   • CloudEvents are sent to the target system using the sink Kamelet

Integration with Other Features

Variables Support

Event channels can use variables in their configurations:

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: s3-archive
spec:
  type: aws-s3
  parameters:
    bucketNameOrArn: "events-archive"
    accessKey: "{{aws_access_key}}"
    secretKey: "{{aws_secret_key}}"
  variables:
    - aws_access_key: "{{sys:AWS_ACCESS_KEY}}"
    - aws_secret_key: "{{sys:AWS_SECRET_KEY}}"

Requirements

Event channels support requirements specification:

apiVersion: weik.io/v1alpha1
kind: EventChannel
metadata:
  name: slack-notifications
spec:
  type: slack
  parameters:
    webhookUrl: "{{slack_webhook}}"
  variables:
    - slack_webhook: "{{sys:SLACK_WEBHOOK_URL}}"
  requirements:
    network: "true"