On-demand self-hosted runner for GitHub Actions

Start your EC2 self-hosted runner right before you need it. Run the job on it. Finally, stop it when you finish. And all this automatically as a part of your GitHub Actions workflow.

It relies on Slab CI bot to do all the heavy-lifting.

See below the YAML code of the depicted workflow.

Table of Contents

• Usage
  • Inputs
  • Outputs
  • Example
• License Summary

Usage

Inputs

Name	Required	Description
mode	Always required.	Specify here which mode you want to use: start to start a new runner, stop to stop the previously created runner.
github-token	Always required.	GitHub Personal Access Token with the repo scope assigned.
slab-url	Always required.	URL to Slab CI server.
job-secret	Always required.	Secret key used by Slab to perform HMAC computation.
backend	Required with start mode.	Backend provider name to look for in slab.toml file in repository that uses the action.
profile	Required with start mode.	Profile to use as described slab.toml file in repository that uses the action.
label	Required with stop mode.	Name of the unique label assigned to the runner.The label is provided by the output of the action in the start mode.The label is used to remove the runner from GitHub when the runner is not needed anymore.

Outputs

Name	Description
label	Name of the unique label assigned to the runner. The label is used in two cases: to use as the input of runs-on property for the following jobs and to remove the runner from GitHub when it is not needed anymore.

Examples

Here's an example workflow. It uses a backend profile declared in ci/slab.toml within the calling repository

name: do-the-job
on: pull_request
jobs:
  start-runner:
    name: Start self-hosted EC2 runner
    runs-on: ubuntu-latest
    outputs:
      label: ${{ steps.start-ec2-runner.outputs.label }}
      ec2-instance-id: ${{ steps.start-ec2-runner.outputs.ec2-instance-id }}
    steps:
      - name: Start EC2 runner
        id: start-ec2-runner
        uses: zama-ai/slab-github-runner@v1
        with:
          mode: start
          github-token: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}
          backend: aws
          profile: cpu-test

  do-the-job:
    # ... #

  stop-runner:
    name: Stop self-hosted EC2 runner
    needs:
      - start-runner # required to get output from the start-runner job
      - do-the-job # required to wait when the main job is done
    runs-on: ubuntu-latest
    if: ${{ always() }} # required to stop the runner even if the error happened in the previous jobs
    steps:
      - name: Stop EC2 runner
        uses: zama-ai/slab-github-runner@v1
        with:
          mode: stop
          github-token: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}
          label: ${{ needs.start-runner.outputs.label }}

License Summary

This code is made available under the MIT license.