action.yml

name: 'Append BuildX nodes'
description: 'Appends docker buildx nodes to an already setup buildex builder.'

inputs:
  builder:
    description: "The builder name from the previous step"
    default: ""
    required: true
  platform:
    description: "For what platform to add the new node (defaults to `linux/arm64`)"
    default: "linux/arm64"
    required: false
  node_name:
    description: "The name of the new node (defaults to `arm`)"
    default: "arm"
    required: false
  driver_opt:
    description: "Some --driver-opt settings - i.e. `nodeselector=kubernetes.io/arch=arm64`"
    default: ""
    required: false
  endpoint:
    description: "An endpoint/context for this node - i.e. `ssh://user@docker-instance.example.com`"
    default: ""
    required: false
  ssh_private_key:
    description: "If the endpoint is a ssh:// endpoint, load this private key"
    default: ""
    required: false

runs:
  using: "composite"
  steps:
    - env:
        BUILDER_NAME: ${{ inputs.builder }}
        NODE_PLATFORM: ${{ inputs.platform }}
        NODE_NAME: ${{ inputs.node_name }}
        DRIVER_OPT: ${{ inputs.driver_opt }}
        ENDPOINT: ${{ inputs.endpoint }}
        SSH_PRIVATE_KEY: ${{ inputs.ssh_private_key }}
      shell: bash
      id: composer_run
      run: |
        set -e

        # Load ssh key allowing access to the remote docker
        if [ ! -z "$SSH_PRIVATE_KEY" ]; then
          # Do not check hostkey (for now)
          mkdir -p ~/.ssh
          cat <<EOF > ~/.ssh/config
          Host *
             StrictHostKeyChecking no
             UserKnownHostsFile=/dev/null
             ControlMaster auto
             ControlPath ~/.ssh/control-%C
             ControlPersist yes
        EOF
          eval $(ssh-agent -s)
          ssh-add <(echo "$SSH_PRIVATE_KEY")
          # Remember this agent also in future steps, because it will be used in the "build" step later on
          echo "SSH_AUTH_SOCK=$SSH_AUTH_SOCK" >> $GITHUB_ENV
        fi

        if [ ! -z "$ENDPOINT" ]; then
          echo "* Testing connection to $ENDPOINT..."
          docker -H $ENDPOINT info
        fi

        # Append the node to the builder
        BUILDX_OPTS=
        if [ ! -z "$DRIVER_OPT" ]; then
          BUILDX_OPTS=--driver-opt $DRIVER_OPT
        fi
        echo "* Appending buildx node $NODE_NAME to builder $BUILDER_NAME (for platform: $NODE_PLATFORM)..."
        docker buildx create --append --name $BUILDER_NAME \
            --node $NODE_NAME --platform $NODE_PLATFORM \
            $BUILDX_OPTS $ENDPOINT

branding:
  icon: 'package'
  color: 'purple'