kobold

README

Kobold

Kobold is a gitbot that automates the process of updating container image tags in a git repository. It listens for webhook events triggered by a container registry, and automatically updates the image tag in the git repository when a new image is pushed.

Motivation

Manually updating image tags in a git repository can be a time-consuming and error-prone process. Kobold was created to automate this process and make it easier for developers to keep their image tags up to date. It is meant to be a companion to other gitops tools such as ArgoCD or FluxCD, which will monitor for changes in git repositories. So an image tag update by kobold might kick of a application rollout with using the new version.

Documentation

The documentation is hosted via github pages and can be viewed at https://bluebrown.github.io/kobold.

Quick Start

You can review the example manifests to see a possible setup.

Typically you would deploy kobold to kubernetes providing your own config file and environment variables for secrets.

For example using kustomize:

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - https://github.com/bluebrown/kobold/releases/latest/download/kobold.manifests.yaml
  - ingress.yaml
configMapGenerator:
  - name: kobold-config
    behavior: replace
    files:
      - ./etc/config.yaml
secretGenerator:
  - name: kobold-env
    behavior: replace
    envs:
      - ./etc/.env

The above config requires to add create some additional resources. Below is the config file for kobold. Adjust this to your needs.

version: v1

endpoints:
  - name: myacr
    type: acr
    path: /acr/107ed4ca-591a-4fee-b6b2-65ef184bb582
    requiredHeaders:
      - key: Authorization
        value: ${SECRET_TOKEN}

repositories:
  - name: github-kobold
    url: https://github.com/bluebrown/kobold
    username: "${MY_GIT_EMAIL}"
    password: "${MY_GIT_PAT}"

subscriptions:
  - name: kobold
    endpointRefs:
      - name: myacr
    repositoryRef:
      name: github-kobold
    branch: main
    strategy: commit

In addition to the above config file, an env file is used for secrets. Kobold will resolve env var references in the config file.

MY_GIT_EMAIL=foo@bar.baz
MY_GIT_PAT=supersecret
SECRET_TOKEN=topsecret

Finally, you need an ingress if you intend to have an external registry dispatch events to kobold. The below example matches the endpoint from the kobold config.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: kobold
spec:
  rules:
    - http:
        paths:
          - pathType: Exact
            path: /acr/107ed4ca-591a-4fee-b6b2-65ef184bb582
            backend:
              service:
                name: kobold
                port:
                  name: http

Development

Use the Makefile via make to run various commands useful for the development.

e2e

You can create an end-to-end setup using kind and gitea.

make e2e-up

Once the stack is deployed, you can access gitea at http://localhost:3000 using kobold as value for both, the username and password.

The ingress controller of the kind cluster is exposed on port 8080 and 8443. So you can publish test events to http://localhost:8080 as this will route the traffic to the kobold server.

Kobold is deployed to the namespace kobold and already configured to listen for generic events and act on the demo repository in gitea, like shown below. You can modify the config.yaml, according to your needs.

You can view the logs of kobold via:

kubectl logs -n kobold deploy/kobold

If you want to test code changes, you can publish a new image to the local registry and restart kobold.

make e2e-reload