Incoming webhook #

Pipelines-as-Code support the concept of incoming webhook URL. It let you trigger PipelineRun in a Repository using a shared secret and URL, instead of creating a new code iteration.

Incoming Webhook URL #

To use incoming webhooks in Pipelines-as-Code, you must configure the incoming field in your Repository CRD. This field references a Secret, which serves as the shared secret, as well as the branches targeted by the incoming webhook. Once configured, Pipelines-as-Code will match PipelineRuns located in your .tekton directory if the on-event annotation of the targetted pipelinerun is targettting a push or incoming event.

If you are not using the github app provider (ie: webhook based provider) you will need to have a git_provider spec to specify a token.

Additionally since we are not able to detect automatically the type of provider on URL. You will need to add it to the git_provider.type spec. Supported values are:

• github
• gitlab
• bitbucket-cloud

Whereas for github-apps this doesn’t need to be added.

GithubApp #

The example below illustrates the use of GithubApp to trigger a PipelineRun based on an incoming webhook URL.

The Repository Custom Resource (CR) specifies the target branch as main and includes an incoming webhook URL with a shared password stored in a Secret called repo-incoming-secret:

---
apiVersion: "pipelinesascode.tekton.dev/v1alpha1"
kind: Repository
metadata:
  name: repo
  namespace: ns
spec:
  url: "https://github.com/owner/repo"
  incoming:
    - targets:
        - main
      secret:
        name: repo-incoming-secret
      type: webhook-url

A PipelineRun is then annotated to target the incoming event and the main branch:

apiVersion: tekton.dev/v1
kind: PipelineRun
metadata:
  name: target_pipelinerun
  annotations:
    pipelinesascode.tekton.dev/on-event: "[incoming]"
    pipelinesascode.tekton.dev/on-target-branch: "[main]"

A secret called repo-incoming-secret is utilized as a shared password to ensure that only authorized users can initiate the PipelineRun:

apiVersion: v1
kind: Secret
metadata:
  name: repo-incoming-secret
  namespace: ns
type: Opaque
stringData:
  secret: very-secure-shared-secret

After setting this up, you will be able to start the PipelineRun with a POST request sent to the controller URL appended with /incoming. The request includes the very-secure-shared-secret, the repository name (repo), the target branch (main), and the PipelineRun name (or the generateName if used) (target_pipelinerun).

As an example here is a curl snippet starting the PipelineRun:

curl -X POST 'https://control.pac.url/incoming?secret=very-secure-shared-secret&repository=repo&branch=main&pipelinerun=target_pipelinerun'

in this snippet, note two things the "/incoming" path to the controller URL and the "POST" method to the URL rather than a simple "GET".

It is important to note that when the PipelineRun is triggered, Pipelines as Code will treat it as a push event and will have the capability to report the status of the PipelineRuns. To obtain a report or a notification, a finally task can be added directly to the Pipeline, or the Repo CRD can be inspected using the tkn pac CLI. The statuses documentation provides guidance on how to achieve this.

Passing dynamic parameter value to incoming webhook #

You can define the value of a any Pipelines-as Code Parameters (including redefining the builtin ones.

You need to list the overridden or added params in the params section of the Repo CR configuration and pass the value in the json body of the incoming webhook request.

You will need to pass the content-type as application/json in the header of your URL request.

Here is a Repository CR letting passing the pull_request_number dynamic variable:

---
apiVersion: "pipelinesascode.tekton.dev/v1alpha1"
kind: Repository
metadata:
  name: repo
  namespace: ns
spec:
  url: "https://github.com/owner/repo"
  incoming:
    - targets:
        - main
      params:
        - pull_request_number
      secret:
        name: repo-incoming-secret
      type: webhook-url

and here is a curl snippet passing the pull_request_number value:

curl -H "Content-Type: application/json" -X POST "https://control.pac.url/incoming?repository=repo&branch=main&secret=very-secure-shared-secret&pipelinerun=target_pipelinerun" -d '{"params": {"pull_request_number": "12345"}}'

The parameter value of pull_request_number will be set to 12345 when using the variable {{pull_request_number}} in your PipelineRun.

Using incoming webhook with webhook based providers #

Webhook based providers (i.e: GitHub Webhook, Gitlab, Bitbucket etc..) supports incoming webhook, using the token provided in the git_provider section.

Here is an example of a Repository CRD matching the target branch main with a GitHub webhook provider:

apiVersion: "pipelinesascode.tekton.dev/v1alpha1"
kind: Repository
metadata:
  name: repo
  namespace: ns
spec:
  url: "https://github.com/owner/repo"
  git_provider:
    type: github
    secret:
      name: "owner-token"
  incoming:
    - targets:
        - main
      secret:
        name: repo-incoming-secret
      type: webhook-url

As noted in the section above, you need to specify a incoming secret inside the repo-incoming-secret Secret.