GitHub Source example shows how to wire GitHub events for consumption by a Knative Service.
You will need:
- An internet-accessible Kubernetes cluster with Knative Serving installed. Follow the installation instructions if you need to create one.
- Ensure Knative Serving is configured with a domain name that allows GitHub to call into the cluster.
- If you're using GKE, you'll also want to assign a static IP address.
- Install Knative
Eventing. Those
instructions also install the default eventing sources, including
the
GitHubSource
we'll use.
To verify the GitHubSource
is working, we will create a simple Knative
Service
that dumps incoming messages to its log. The service.yaml
file
defines this basic service.
apiVersion: serving.knative.dev/v1alpha1
kind: Service
metadata:
name: github-message-dumper
spec:
runLatest:
configuration:
revisionTemplate:
spec:
container:
image: gcr.io/knative-releases/github.com/knative/eventing-sources/cmd/message_dumper
Enter the following command to create the service from service.yaml
:
kubectl --namespace default apply --filename service.yaml
Create a personal access token for GitHub that the GitHub source can use to register webhooks with the GitHub API. Also decide on a secret token that your code will use to authenticate the incoming webhooks from GitHub (secretToken).
The token can be named anything you find convenient. The Source
requires repo:public_repo
and admin:repo_hook
, to let it fire
events from your public repositories and to create webhooks for those
repositories. Copy and save this token; GitHub will force you to
generate it again if misplaced.
Here's an example for a token named "GitHubSource Sample" with the recommended scopes:
Update githubsecret.yaml
with those values. If your generated access
token is 'personal_access_token_value'
and you choose your secretToken
as 'asdfasfdsaf'
, you'd modify githubsecret.yaml
like so:
apiVersion: v1
kind: Secret
metadata:
name: githubsecret
type: Opaque
stringData:
accessToken: personal_access_token_value
secretToken: asdfasfdsaf
Hint: you can makeup a random secretToken with:
head -c 8 /dev/urandom | base64
Then, apply the githubsecret using kubectl
:
kubectl --namespace default apply --filename githubsecret.yaml
In order to receive GitHub events, you have to create a concrete Event
Source for a specific namespace. Be sure to replace the
ownerAndRepository
value with a valid GitHub public repository owned
by your GitHub user.
apiVersion: sources.eventing.knative.dev/v1alpha1
kind: GitHubSource
metadata:
name: githubsourcesample
spec:
eventTypes:
- pull_request
ownerAndRepository: <YOUR USER>/<YOUR REPO>
accessToken:
secretKeyRef:
name: githubsecret
key: accessToken
secretToken:
secretKeyRef:
name: githubsecret
key: secretToken
sink:
apiVersion: serving.knative.dev/v1alpha1
kind: Service
name: github-message-dumper
Then, apply that yaml using kubectl
:
kubectl --namespace default apply --filename github-source.yaml
Verify the GitHub webhook was created by looking at the list of webhooks under the Settings tab in your GitHub repository. A hook should be listed that points to your Knative cluster with a green check mark to the left of the hook URL, as shown below.
Create a pull request in your GitHub repository. We will verify that the GitHub events were sent into the Knative eventing system by looking at our message dumper function logs.
kubectl --namespace default get pods
kubectl --namespace default logs github-message-dumper-XXXX user-container
You should log lines similar to:
2018/11/08 18:25:34 Message Dumper received a message: POST / HTTP/1.1
Host: github-message-dumper.knative-demo.svc.cluster.local
Accept-Encoding: gzip
Ce-Cloudeventsversion: 0.1
Ce-Eventid: a8d4cf20-e383-11e8-8069-46e3c8ad2b4d
Ce-Eventtime: 2018-11-08T18:25:32.819548012Z
Ce-Eventtype: dev.knative.source.github.pull_request
Ce-Source: https://github.com/someuser/somerepo/pull/1
Content-Length: 21060
Content-Type: application/json
User-Agent: Go-http-client/1.1
X-B3-Parentspanid: b2e514c3dbe94c03
X-B3-Sampled: 1
X-B3-Spanid: c85e346d89c8be4e
X-B3-Traceid: abf6292d458fb8e7
X-Envoy-Expected-Rq-Timeout-Ms: 60000
X-Envoy-Internal: true
X-Forwarded-For: 127.0.0.1, 127.0.0.1
X-Forwarded-Proto: http
X-Request-Id: 8a2201af-5075-9447-b593-ec3a243aff52
{"action":"opened","number":1,"pull_request": ...}
You can remove the Github webhook by deleting the Github source:
kubectl --namespace default delete --filename github-source.yaml
Similarly, you can remove the Service and Secret via:
kubectl --namespace default delete --filename service.yaml
kubectl --namespace default delete --filename githubsecret.yaml