OpenWhisk NodeJS Runtime for Knative

This directory is used to build and test the OpenWhisk NodeJS Action runtime for Knative.

Pre-requisites

Complete the pre-requisites and Knative installation and configuration instructions in the top-level README for this repository.

Verify your Kubernetes & Knative pods are running

Verify kube-system, istio-system, and knative-xxx pods are all Running

$ kubectl get pods --all-namespaces

$ kubectl get pods --all-namespaces
NAMESPACE          NAME                                            READY   STATUS      RESTARTS   AGE
istio-system       cluster-local-gateway-547467ccf6-p8n72          1/1     Running     1          8d
istio-system       istio-citadel-7d64db8bcf-m7gsj                  1/1     Running     0          8d
istio-system       istio-cleanup-secrets-8lzj4                     0/1     Completed   0          8d
istio-system       istio-egressgateway-6ddf4c8bd6-2dxhc            1/1     Running     1          8d
istio-system       istio-galley-7dd996474-pdd6h                    1/1     Running     1          8d
istio-system       istio-ingressgateway-84b89d647f-cxrwx           1/1     Running     1          8d
istio-system       istio-pilot-86bb4fcbbd-5ns5q                    2/2     Running     0          8d
istio-system       istio-pilot-86bb4fcbbd-vd2xr                    2/2     Running     0          8d
istio-system       istio-pilot-86bb4fcbbd-zstrw                    2/2     Running     0          8d
istio-system       istio-policy-5c4d9ff96b-559db                   2/2     Running     1          8d
istio-system       istio-sidecar-injector-6977b5cf5b-94hj5         1/1     Running     0          8d
istio-system       istio-statsd-prom-bridge-b44b96d7b-kzkzc        1/1     Running     0          8d
istio-system       istio-telemetry-7676df547f-jp952                2/2     Running     1          8d
istio-system       knative-ingressgateway-75644679c7-c2kxj         1/1     Running     1          8d
knative-build      build-controller-658d64d9bd-6qp2c               1/1     Running     0          8d
knative-build      build-webhook-6bb747665f-v8nk2                  1/1     Running     1          8d
knative-eventing   eventing-controller-cfbb757bd-czx99             1/1     Running     0          8d
knative-eventing   in-memory-channel-controller-75d6cc4b77-6c8st   1/1     Running     1          8d
knative-eventing   in-memory-channel-dispatcher-c89db8bb8-phlxw    2/2     Running     7          8d
knative-eventing   webhook-5fbb8dbcc7-nhwp5                        1/1     Running     0          8d
knative-serving    activator-69b8474d6b-58hh2                      2/2     Running     1          8d
knative-serving    autoscaler-6579b57774-cvvzj                     2/2     Running     1          8d
knative-serving    controller-66cd7d99df-hgswh                     1/1     Running     0          8d
knative-serving    webhook-6d9568d-czt8m                           1/1     Running     0          8d
knative-sources    controller-manager-0                            1/1     Running     1          8d
kube-system        coredns-86c58d9df4-ms8qs                        1/1     Running     0          8d
kube-system        coredns-86c58d9df4-x29vt                        1/1     Running     0          8d
kube-system        etcd-docker-desktop                             1/1     Running     3          8d
kube-system        kube-apiserver-docker-desktop                   1/1     Running     3          8d
kube-system        kube-controller-manager-docker-desktop          1/1     Running     5          8d
kube-system        kube-proxy-mltsm                                1/1     Running     0          8d
kube-system        kube-scheduler-docker-desktop                   1/1     Running     5          8d

Install the BuildTemplate for the NodeJS runtime

$ kubectl apply --filename buildtemplate.yaml
buildtemplate.build.knative.dev/openwhisk-nodejs-runtime created

Verify BuildTemplate

$ kubectl get buildtemplate
NAME                       AGE
openwhisk-nodejs-runtime   2h

or to see the full resource:

$ kubectl get buildtemplate -o yaml

apiVersion: v1
items:
- apiVersion: build.knative.dev/v1alpha1
  kind: BuildTemplate
  metadata:
    annotations:
      kubectl.kubernetes.io/last-applied-configuration {}
    creationTimestamp: "2019-02-07T16:10:46Z"
    generation: 1
    name: openwhisk-nodejs-runtime
    namespace: default
    resourceVersion: "278166"
    selfLink: /apis/build.knative.dev/v1alpha1/namespaces/default/buildtemplates/openwhisk-nodejs-runtime
    uid: ed5bb6e0-2af2-11e9-a25d-025000000001
  spec:
    generation: 1
    parameters:
    - description: name of the image to be tagged and pushed
      name: TARGET_IMAGE_NAME
    - default: latest
      description: tag the image before pushing
      name: TARGET_IMAGE_TAG
    - description: name of the dockerfile
      name: DOCKERFILE
    - default: "false"
      description: flag to indicate debug mode should be on/off
      name: OW_DEBUG
    - description: name of the action
      name: OW_ACTION_NAME
    - description: JavaScript source code to be evaluated
      name: OW_ACTION_CODE
    - default: main
      description: name of the function in the "__OW_ACTION_CODE" to call as the action
        handler
      name: OW_ACTION_MAIN
    - default: "false"
      description: flag to indicate zip function, for zip actions, "__OW_ACTION_CODE"
        must be base64 encoded string
      name: OW_ACTION_BINARY
    steps:
    - args:
      - -c
      - |
        cat <<EOF >> ${DOCKERFILE}
          ENV __OW_DEBUG "${OW_DEBUG}"
          ENV __OW_ACTION_NAME "${OW_ACTION_NAME}"
          ENV __OW_ACTION_CODE "${OW_ACTION_CODE}"
          ENV __OW_ACTION_MAIN "${OW_ACTION_MAIN}"
          ENV __OW_ACTION_BINARY "${OW_ACTION_BINARY}"
        EOF
      command:
      - /busybox/sh
      image: gcr.io/kaniko-project/executor:debug
      name: add-ow-env-to-dockerfile
    - args:
      - --destination=${TARGET_IMAGE_NAME}:${TARGET_IMAGE_TAG}
      - --dockerfile=${DOCKERFILE}
      image: gcr.io/kaniko-project/executor:latest
      name: build-openwhisk-nodejs-runtime
kind: List
metadata:
  resourceVersion: ""
  selfLink: ""

Building a Knative service using the NodeJS BuildTemplate

We will use the simple “helloworld” test case to demonstrate how to use Knative to Build your function into container image and then deploy it as a Service.

The testcase resides within this repo. at:

• tests/helloworld/

For a complete listing of testcases, please view the README in the tests subdirectory.

Build HelloWorld

Configure build.yaml

You will need to configure the build template to point to the Docker Hub repo. you wish the image to be “pushed” to once built.

To do this,

• Copy build.yaml.tmpl to build.yaml.
• Replace ${DOCKER_USERNAME} with your own Docker username in build.yaml.

If you wish to run repeated tests you MAY set an environment variable and use sed to replace the ${DOCKER_USERNAME} within any of the test's Kubernetes Build YAML files as follows:

# If you have not already exported your Dockerhub username, use the following command:
export DOCKERHUB_USERNAME_PLAIN_TEXT="myusername"

# Generate the build file from the template using your Dockerhub username set in the environment
sed 's/${DOCKER_USERNAME}/'"$DOCKERHUB_USERNAME_PLAIN_TEXT"'/' build.yaml.tmpl > build.yaml

Deploy the runtime

kubectl apply -f build.yaml

This creates a pod with a NodeJS runtime and all the action metadata (action code, main function name, etc) integrated into the container image.

Troubleshootinh the build

If for any reason there is a failure creating the pod, we can troubleshoot the deployment with:

kubectl get pods

kubectl get pods <build-pod-name> -o yaml

Which lists the containers and their status under initContainerStatuses:

• build-step-credential-initializer
• build-step-git-source-0
• build-step-add-ow-env-to-dockerfile
• build-step-build-openwhisk-nodejs-runtime

kubectl logs

Now, the logs of each of these build steps (containers) can be retrieved using:

kubectl logs <build-pod-name> -c <container-name>

For example:

kubectl logs nodejs-10-helloworld-pod-71d4d2 -c build-step-build-openwhisk-nodejs-runtime
INFO[0007] Downloading base image node:10.15.0-stretch
error building image: getting stage builder for stage 0: Get https://index.docker.io/v2/: net/http: TLS handshake timeout

kubectl exec

And, we can get to a shell in any of these containers with:

kubectl exec <build-pod-name> -- env

Run HelloWorld

Configure service.yaml

Now that you have built the OpenWhisk NodeJS runtime image with the helloworld function “baked” into it, you can can deploy the image as a Knative Service.

You will need to configure the Service template to point to the Docker Hub repo. where your Knative OpenWhisk runtime (with the Hello World function) will be “pulled” from.

To do this,

• Copy service.yaml.tmpl to service.yaml.
• Replace ${DOCKER_USERNAME} with your own Docker username in service.yaml.

As described for ‘build.yaml.tmpl’, you MAY set an environment variable and use sed to replace the ${DOCKER_USERNAME} within any of the test's Kubernetes Build YAML files as follows:

export DOCKERHUB_USERNAME_PLAIN_TEXT="myusername"
sed 's/${DOCKER_USERNAME}/'"$DOCKERHUB_USERNAME_PLAIN_TEXT"'/' service.yaml.tmpl > service.yaml

apiVersion: serving.knative.dev/v1alpha1
kind: Service
metadata:
  name: nodejs-helloworld
  namespace: default
spec:
  runLatest:
    configuration:
      revisionTemplate:
        spec:
          container:
            image: docker.io/${DOCKER_USERNAME}/nodejs-10-helloworld

Deploy the runtime

kubectl apply -f service.yaml

See Hello World Live in Action