Github action to simplify deploys to Google Compute Engine.

This action will...

1. Clone an existing instance template (using it as a base).
2. Update metadata config of the newly created instance template to run a startup script.
3. Tell the instance group manager to perform a rolling update with the new instance template.

Set up the following resources manually in the Cloud Console or use a tool like Terraform.

• Create a base instance template to be cloned by this action.
• Create a managed instance group. Please note that currently only regional instance groups are supported.
• Create Service Account with Roles Compute Admin and Service Account User and export a new JSON key.

By default this action expects a deploy.yml in the root directory of the repository. Here is an example:

common:
  labels:
    gitsha: ${{GITHUB_SHA}}

deploys:
  - name: my-app-deploy
    region: us-central1
    instance_group: my-app-instance-group
    instance_template_base: my-app-instance-template-base
    instance_template: my-app-${{GITHUB_RUN_NUMBER}}-${{GITHUB_SHA}}
    cloud_init: cloud-init.yml # see example dir
    labels: # will also have gitsha from common section
      version: ${{APP_VERSION}}
    tags:
      - my-tag123
    update_policy:
      min_ready_sec: 30

delete_instance_templates_after: false

Environment variables can be used in deploy.yml, startup_script, shutdown_script and cloud_init files. The syntax is ${{FOO}} and supports substring extraction, i.e. ${{GITHUB_SHA:0:7}}:

${{VAR:position}}        - Extracts substring from $VAR at "position"
${{VAR:position:length}} - Extracts "length" characters of substring from $VAR at "position"

Github sets a bunch of default environment variables.

uses: mattes/gce-deploy-action@v5
with:
  creds: ${{ secrets.GOOGLE_APPLICATION_CREDENTIALS }}

• My own Heroku in 30 mins - Deploy Rails apps to Google Cloud Compute Engine
• Managed Instance Groups
• Container-Optimized OS
• cloud-init
• startup scripts
• Configuring an Instance