zuul-operator/CONTRIBUTE.md
Tristan Cacqueray 0f759638f3 Update dhall-kubernetes version to v4.0.0
This change update the kubernetes binding to use the new
Optional types. The main consequence is that all the fields that
are optional needs to be prefixed with Some. This let us remove
the `--omit-empty` parameter resulting in cleaner resources where
we don't need to set a dummy emptyDir medium value.

See this issue for the details:
https://github.com/dhall-lang/dhall-kubernetes/issues/86

Change-Id: I23a0a028909208cd58f57a6f07ee93090b3f3a1a
2020-04-06 13:36:46 +00:00

105 lines
2.9 KiB
Markdown

# Developper documentation
The zuul operator is a container application that manages a
zuul service described by a high level description (named CR).
Its goal is to create the kubernetes resources and to perform
the runtime operations.
To describe the kubernetes resources such as Deployment and Service,
the zuul operator uses the Dhall language to convert the CR input
into the kubernetes resources.
To apply and manage the resources, the zuul operator uses Ansible
through the operator-framework to execute the roles/zuul when
a Zuul CR is requested.
The following sections explain how to evaluate the Dhall configuration
and the Ansible task locally, outside of a kubernetes pod.
This simplifies the development and contribution process.
## Setup tools
Install the `dhall-to-yaml` and `yaml-to-dhall` tool by following this tutorial:
https://docs.dhall-lang.org/tutorials/Getting-started_Generate-JSON-or-YAML.html#installation
Or use the zuul-operator image:
```bash
CR="podman"
alias dhall-to-yaml="$CR run --rm --entrypoint dhall-to-yaml -i docker.io/zuul/zuul-operator"
alias yaml-to-dhall="$CR run --rm --entrypoint yaml-to-dhall -i docker.io/zuul/zuul-operator"
```
## Evaluate the dhall expression manually
First you need to convert a CR spec to a dhall record, for example using the test file `playbooks/files/cr_spec.yaml`:
```bash
INPUT=$(yaml-to-dhall "(./conf/zuul/input.dhall).Input.Type" < playbooks/files/cr_spec.yaml)
```
Then you can evaluate the resources function, for example to get the scheduler service:
```bash
dhall-to-yaml --explain <<< "(./conf/zuul/resources.dhall ($INPUT)).Components.Zuul.Scheduler"
```
Or get all the kubernetes resources:
```bash
dhall-to-yaml <<< "(./conf/zuul/resources.dhall ($INPUT)).List"
```
## Run the ansible roles locally
Given a working `~/.kube/config` context, you can execute the Ansible roles directly using:
```bash
export ANSIBLE_CONFIG=playbooks/files/ansible.cfg
ansible-playbook -v playbooks/files/local.yaml
```
Then cleanup the resources using:
```bash
ansible-playbook -v playbooks/files/local.yaml -e k8s_state=absent
```
## Run the integration test locally
First you need to build the operator image:
```bash
make build
```
Or you can update an existing image with the local dhall and ansible content:
```bash
./playbooks/files/update-operator.sh
```
Then you can run the job using:
```bash
ansible-playbook -e @playbooks/files/local-vars.yaml -v playbooks/zuul-operator-functional/run.yaml
ansible-playbook -e @playbooks/files/local-vars.yaml -v playbooks/zuul-operator-functional/test.yaml
```
Alternatively, you can run the job without using the operator pod by including the ansible role directly.
To do that run the playbooks with:
```
ansible-playbook -e use_local_role=true ...
```
## Delete all kubernetes resources
To wipe your namespace run this command:
```bash
kubectl delete $(for obj in statefulset deployment service secret; do kubectl get $obj -o name; done)
```