Using Garden in CircleCI

Prerequisites

In addition to the prerequisites in the Portable CI Pipelines that Run Anywhere doc.

For the purposes of this example we'll be using CircleCI and deploying to a Google Kubernetes Engine (GKE) cluster.

Project overview

The project is based on our basic demo-project example, but configured for multiple environments. Additionally it contains a CircleCI config file. You'll find the entire source code here.

The CI pipeline is configured so that Garden tests the project and deploys it to a preview environment on every pull request. Additionally, it tests the project and deploys it to a separate staging environment on every merge to the main branch.

To see it in action, you can fork the repository and follow the set-up steps below. Once you've set everything up, you can submit a pull request to the fork to trigger a CircleCI job which in turns deploys the project to your remote Kubernetes cluster.

Configure remote environments

Configuring Garden to work against a remote Kubernetes cluster is explained step by step in our Remote Kubernetes guide.

For this project we're using three environments: local, preview and staging. The local environment is the default and is configured for a local Kubernetes cluster that runs on the user's machine. The other two run on remote clusters.

We deploy to the preview environment every time someone makes a pull request on Github. The configuration looks like this:

# garden.yml
apiVersion: garden.io/v2
kind: Project
name: ci-demo-project
environments:
  ...
  - name: preview
    defaultNamespace: preview-${local.env.CIRCLE_BRANCH || local.username}
providers:
  - name: kubernetes
    environments: [preview]
    context: my-preview-cluster
    defaultHostname: ${environment.namespace}.preview.my-domain
    buildMode: cluster-buildkit

Notice that we're using the CIRCLE_BRANCH environment variable to label the project namespace. This ensures that each pull request gets deployed into its own namespace.

The staging environment is configured in a similar manner. The relevant CI job is triggered on merges to the main branch.

You'll find the rest of the config here.

Configure the kubectl context

We need to make sure that it can access our remote cluster. We do this by setting up a kubectl context on the CI agent. How you set this up will vary by how and where you have deployed your cluster. What follows is specific to GKE.

We create a re-usable command for configuring the kubectl context:

# .circleci/config
commands:
  configure_kubectl_context:
    description: Configure the kubectl context so that we can access our remote cluster
    steps:
      - run:
          name: Configure kubectl context via gcloud
          command: |
            gcloud --quiet components update
            echo $GCLOUD_SERVICE_KEY | gcloud auth activate-service-account --key-file=-
            gcloud --quiet config set project $GCLOUD_PROJECT_ID && gcloud --quiet config set compute/zone $GCLOUD_COMPUTE_ZONE
            gcloud --quiet container clusters get-credentials $GCLOUD_CLUSTER_ID --zone $GCLOUD_COMPUTE_ZONE
            gcloud --quiet auth configure-docker

The commands use the following environment variables that you can set on the Project Environment Variables page (see here) in the CircleCI dashboard:

• GCLOUD_SERVICE_KEY: Follow these instructions to get a service account key.
• GCLOUD_PROJECT_ID, GCLOUD_COMPUTE_ZONE, and GCLOUD_CLUSTER_ID: These you'll find under the relevant project in your Google Cloud Platform console.

Please refer to this doc for more information on using the Google Cloud SDK in CircleCI.

You'll find the entire CircleCI config for this projecthere.

Running Garden commands in CircleCI

Now that we have everything set up, we can add the project to CircleCI and start using Garden in our CI pipelines.

Note: Below we use the gardendev/garden-gcloud container image, that extends the standardgardendev/garden image to bundle the gcloud binary (Google Cloud CLI). For an overview of all official Garden convenience containers, please refer to the reference guide for DockerHub containers.

Here's what our preview job looks like:

# .circleci/config
jobs:
  preview:
    docker:
      - image: gardendev/garden-gcloud:bonsai-alpine
    environment:
      GARDEN_LOG_LEVEL: verbose # set the log level to your preference here
    steps:
      - checkout
      - configure_kubectl_context
      - run:
          name: Test project
          command: garden test --env=preview
      - run:
          name: Deploy project
          command: garden deploy --env=preview

Notice that there are no configuration steps outside of just configuring the kubectl context. And no matter how you change your stack, these steps will remain the same, making for a highly portable workflow—and much less fiddling around with CI!