docs/serving/samples/gitwebhook

gitwebhook

A simple git webhook handler that demonstrates interacting with github. Modeled after GCF example

Prerequisites

1. Install Knative Serving
2. Install docker

Setup

Build the app container and publish it to your registry of choice:

REPO="gcr.io/<your-project-here>"

# Build and publish the container, run from the root directory.
docker build \
  --build-arg SAMPLE=gitwebhook \
  --tag "${REPO}/sample/gitwebhook" \
  --file=sample/Dockerfile.golang .
docker push "${REPO}/sample/gitwebhook"

# Replace the image reference with our published image.
perl -pi -e "s@github.com/knative/serving/sample/gitwebhook@${REPO}/sample/gitwebhook@g" sample/gitwebhook/*.yaml

# Deploy the Knative Serving sample
kubectl apply -f sample/gitwebhook/sample.yaml

Exploring

Once deployed, you can inspect the created resources with kubectl commands:

# This will show the Route that we created:
kubectl get route -o yaml

# This will show the Configuration that we created:
kubectl get configurations -o yaml

# This will show the Revision that was created by our configuration:
kubectl get revisions -o yaml

To make this service accessible to github, we first need to determine its ingress address (might have to wait a little while until EXTERNAL-IP gets assigned):

watch kubectl get svc knative-ingressgateway -n istio-system
NAME                     TYPE           CLUSTER-IP     EXTERNAL-IP      PORT(S)                                      AGE
knative-ingressgateway   LoadBalancer   10.23.247.74   35.203.155.229   80:32380/TCP,443:32390/TCP,32400:32400/TCP   2d

Once the EXTERNAL-IP gets assigned to the cluster, you need to assign a DNS name for that IP address. Using GCP DNS

So, you'd need to create an A record for demostuff.aikas.org pointing to 35.202.30.59.

Then you need to go to github and [set up a webhook](https://cloud.google.com/community/tutorials/github-auto-assign-r eviewers-cloud-functions). For the Payload URL however, use your DNS entry you created above, so for my example it would be: http://demostuff.aikas.org/

Create a secret that has access to the tokens. Take the Secret you used for the webhook (secretToken) and the generated access token (accessToken) (as per the above webhook)

echo -n "your-chosen-secret-token" > secretToken
echo -n "github-generated-access-token" > accessToken
kubectl create secret generic githubsecret --from-file=./secretToken --from-file=./accessToken

Then create a PR for the repo you configured the webhook for, and you'll see that the Title will be modified with the suffix '(looks pretty legit)'

Cleaning up

To clean up the sample service:

kubectl delete -f sample/gitwebhook/sample.yaml