jobs:
  startServer:
    name: Build
    runs-on: ubuntu-latest
    steps:
    # create a new server
    - name: Create new Hetzner server
      id: setup_server # set this to get the output in steps.setup_server.outputs
      uses: saitho/hetzner-cloud-action@master
      with:
        action: create
        server_name: pr-${{ github.run_id }}
        server_image: ubuntu-18.04
        server_location: fsn1
        server_ssh_key_name: github-ci
        wait_for_ssh: 1 # wait until SSH on port 22 is ready for connections
      env:
        API_TOKEN: ${{ secrets.HETZNER_TOKEN }}
    # IPv4 address of created server is available in hcloud_server_created_ipv4
    # if CI is provided the private SSH key for the key named "server_ssh_key_name" it can connect via SSH
    - name: Work with the server
      run: echo 'do stuff on ${{ steps.setup_server.outputs.hcloud_server_created_ipv4 }}'
    # remove server
    - name: Remove Hetzner server
      uses: saitho/hetzner-cloud-action@master
      with:
        action: remove
        server_id: ${{ steps.setup_server.outputs.hcloud_server_id }}
      if: always() # make sure server is removed even if steps in between fail
      env:
        API_TOKEN: ${{ secrets.HETZNER_TOKEN }}

In some cases the server may need some more time to be ready for connections. Unfortunately GitHub runners can't use ping to check if the server can be reached. You may want to add a sleep step after creating the server in order to make sure it's ready when working with it.

jobs:
  startServer:
    steps:
      # ... create step here ...
      - name: wait for server
        run: sleep 5 # wait for 5 seconds

If you're specifically wait for the SSH port 22 to be available, set wait_for_ssh=1 as input.

You can set up an SSH key which you or your CI can use to connect to the newly created server. Add the public key to your Hetzner project and the private key to your job's secrets.

Make sure to set server_ssh_key_name to the name you specified on your Hetzner project.

Create a new SSH key without a passphrase:

ssh-keygen -f ./my-ssh-key -m pem -C gh-actions

This will create two files: my-ssh-key (private key) and my-ssh-key.pub (public key).

Go to your Hetzner project and create a new SSH key entry with the contents of my-ssh-key.pub and choose a name (e.g. github-ci).

Next, go to your GitHub repository and add a new secret with the contents of my-ssh-key and choose a name (e.g. SSH_PRIVATE_KEY)

You can then use any SSH provider GitHub action to use the key within your build, e.g.

- uses: webfactory/[email protected]
  with:
    ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }}

Also in the definition for saitho/hetzner-cloud-action make sure to set server_ssh_key_name to the name you chose before (e.g. github-ci). If you can't connect to the server via SSH afterwards, you may want to set wait_for_ssh to make sure saitho/hetzner-cloud-action only continues when port 22 is available.