convention-server

Sample convention webserver

The image contains a simple Go webserver server.go, that will by default, listens on port 9000 and expose a service at /.

The webserver can only be called with request body of type PodConventionContext of APIGroup webhooks.conventions.carto.run. If not, server responds with 400 status code. When called with correct request body type, the server emits a response of object type PodConventionContext of APIGroup webhooks.conventions.carto.run and for this sample, appends an environment variable.

Trying out

Build and run the convention server:

# either, from source:
ko apply -f server.yaml

# or, from a release distribution:
kubectl create -f <(kbld -f server.yaml -f ../.imgpkg/images.yml)

To verify the setup, add an Workload and check the status

kubectl create -f workload.yaml

kubectl get podintents.conventions.carto.run sample -oyaml

If everything works correctly, the status will contain a transformed template that includes an environment variable added by the convention server.

apiVersion: conventions.carto.run/v1alpha1
kind: PodIntent
metadata:
  creationTimestamp: "2021-01-20T02:06:33Z"
  generation: 1
  name: sample
  namespace: default
  resourceVersion: "6978954"
  selfLink: /apis/conventions.carto.run/v1alpha1/namespaces/default/podintents/sample
  uid: d8ade195-7f9d-4694-99b1-47b01052461b
spec:
  template:
    metadata: {}
    spec:
      containers:
      - image: ubuntu
        name: workload
        resources: {}
status:
  conditions:
  - lastTransitionTime: "2021-01-20T02:06:34Z"
    status: "True"
    type: ConventionsApplied
  - lastTransitionTime: "2021-01-20T02:06:34Z"
    status: "True"
    type: Ready
  observedGeneration: 1
  template:
    metadata:
      annotations:
        conventions.carto.run/applied-conventions: sample/add-env-var
    spec:
      containers:
      - image: ubuntu
        name: workload
        env:
        - name: CONVENTION_SERVER
          value: HELLO FROM CONVENTION
        resources: {}