.github/gh-actions-self-hosted-runners/self-hosted-linux/README.md

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# GitHub Actions - Self-hosted Linux Runners
These folders contain the required resources to deploy the GitHub Actions self-hosted runners for the workflows running in Ubuntu OS.
* /docker
    * Dockerfile and entrypoint: Resources needed to create a new self-hosted-runner image.
    * docker-compose.yml: In case you would like to test and run the self-hosted runner locally.

* /kubernetes
    * Kubernetes files to create the resources needed to deploy the self-hosted runners.

## Docker

#### How to build a new image and push it to the Artifact Registry?
* Create the image locally

`docker build -t $LOCAL_IMAGE_NAME:TAG .`

* Tag the local image with the GCP repository name

`docker tag $LOCAL_IMAGE_NAME LOCATION-docker.pkg.dev/PROJECT-ID/REPOSITORY/IMAGE:latest`

* Make sure you are authenticated to the gcloud repository

`gcloud auth configure-docker us-central1-docker.pkg.dev`

* Push the tagged image to the repository

`docker push LOCATION-docker.pkg.dev/PROJECT-ID/REPOSITORY/IMAGE:latest`

* _**Important: Please add the commit hash as a tag when a new image is uploaded.**_

#### How to run a self-hosted runner locally?

* Create a `.var.env` file from the `example.var.env` file and replace the corresponding values:
    * GOOGLE_APPLICATION_CREDENTIALS: Path where the json file will be stored (Same path as the one given in the docker-compose.yml file)
    * CLOUD_FUNCTION_NAME: Function where the self-hosted runner will get the RUNNER_TOKEN
    * ORG_RUNNER_GROUP: Name of the GitHub Actions Runner Group. You can find it here: https://github.com/organizations/ORG_NAME/settings/actions/runner-groups
    * ORG_NAME: Name of the Organization
    * GCP_REGION: GCP Region where your Cloud Function is deployed
    * GCP_PROJECT_ID: GCP Project ID where your Cloud Function is deployed


* Run the container

`docker compose up`

* You will be able to see the self-hosted runner in the Settings of your GitHub repository

## Kubernetes

For the current implementation we are using Google Kubernetes Engine (GKE) as a container orchestration platform.

* Configure your Kubernetes local context

`gcloud container clusters get-credentials $GCP_CLUSTER_NAME --zone $GCP_REGION --project $GCP_PROJECT-ID`

* Create the desired k8s namespace

`kubectl create namespace $NAMESPACE`

* Create the GKE secret from a json file

`kubectl create secret generic $k8s_SECRET_NAME --from-file=key.json=$LOCAL_PATH --namespace $NAMESPACE`

* Update the `github-actions-secrets.yml` file with its corresponding values encrypted in base64

`echo -n "$VARIABLE_VALUE" | base64`

* Replace in `github-actions-deployment.yml` file the `$IMAGE_URL` variable with the corresponding image URL: `GCP_LOCATION-docker.pkg.dev/GCP_PROJECT_ID/REPOSITORY_NAME/IMAGE_NAME`


* In case you would like to create the deployment from scratch, run the `run-k8s-deployment.sh` script to execute the Kubernetes deployment in the GKE cluster.
    * **Important: Make sure you have the GKE context selected in your local machine:** `kubectl config current-context`

`./run-k8s-deployment.sh $NAMESPACE`

* Otherwise, apply only the changes. **Important: Make sure you have the GKE context selected in your local machine:** `kubectl config current-context`

`kubectl apply -f github-actions-$FILE_NAME.yml --namespace $NAMESPACE`

* In case you would like to delete all the Kubernetes resources, run the `delete-k8s-deployment.sh` script with its corresponding namespace value.

`./delete-k8s-deployment.sh $NAMESPACE`