Cloud Events - Java and Vert.x

    1. The default mode has the app reply to your input events with the output event, which is simplest for demonstrating things working in isolation, but is also the model for working for the Knative Eventing concept. The input event is modified assigning a new source and type attribute.

    2. K_SINK mode has the app send events to the destination encoded in $K_SINK, which is useful to demonstrate how folks can synthesize events to send to a Service or Broker when not initiated by a Broker invocation (e.g. implementing an event source). The input event is modified assigning a new source and type attribute.

    The application will use $K_SINK-mode whenever the environment variable is specified.

    Do the following steps to create the sample code and then deploy the app to your cluster. You can also download a working copy of the sample, by running the following commands:

    • A Kubernetes cluster with Knative installed and DNS configured. Follow the installation instructions if you need to create one.
    • installed and running on your local machine, and a Docker Hub account configured (we’ll use it for a container registry).

    To build the image, run:

    1. mvn compile jib:build -Dimage=<image_name>

    To deploy the Knative Service, look in the service.yaml and replace <image> with the deployed image name. Then run:

    1. kubectl apply -f service.yaml

    kn

    If using kn to deploy:

    Get the URL for your Service with:

    1. $ kubectl get ksvc
    2. NAME                URL                                            LATESTCREATED             LATESTREADY               READY   REASON
    3. cloudevents-vertx   http://cloudevents-java.sslip.io                 cloudevents-vertx-86h28   cloudevents-vertx-86h28   True

    Then send a CloudEvent to it with:

    1.     -X POST -v \
    3.     -H "ce-specversion: 1.0"  \
    4.     -H "ce-source: http://curl-command"  \
    5.     -H "ce-type: curl.demo"  \
    6.     -H "ce-id: 123-abc"  \
    7.     -d '{"name":"Dave"}' \
    8.     http://cloudevents-java.sslip.io

    You’ll see on the console:

    1. > POST / HTTP/1.1
    2. > Host: localhost:8080
    3. > User-Agent: curl/7.69.1
    4. > Accept: */*
    5. > content-type: application/json
    6. > ce-source: http://curl-command
    8. > ce-id: 123-abc
    9. > Content-Length: 15
    10. >
    11. < HTTP/1.1 202 Accepted
    12. < ce-specversion: 1.0
    13. < ce-id: 123-abc
    14. < ce-source: https://github.com/knative/docs/docs/serving/samples/cloudevents/cloudevents-vertx
    15. < ce-type: curl.demo
    16. < content-type: application/json
    17. < content-length: 15
    18. <

    To remove the sample app from your cluster, delete the service:

    yaml

    Run:

    1. kubectl delete --filename service.yaml

    kn