src/data/startup.yaml

#cloud-config
#
# Copyright 2021 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# This script runs customization scripts on a COS VM instance. It pulls
# source from GCS and executes it.

write_files:
- path: /tmp/startup.sh
  permissions: 0644
  content: |
    set +o history
    set -o errexit
    set -o pipefail
    set -o nounset
    set -x

    status() {
      $@ 2>&1 | sed "s/^/BuildStatus: /"
      return "${PIPESTATUS[0]}"
    }

    # Setup the scratch disk for use among tasks that need it.
    # Directories are created for any task that might use them.
    # E.g. there will be a /mnt/disks/scratch/gpu for the gpu step
    # and potentially other directories for other steps.
    setup_scratch_disk() {
      status mkdir -p /mnt/disks/scratch
      status resize2fs -f /dev/disk/by-label/SCRATCH
      status mount /dev/disk/by-label/SCRATCH /mnt/disks/scratch
      status mkdir -p /mnt/disks/scratch/gpu
    }

    # To make sure that ARCH gets set properly, this function cannot run in a
    # subshell.
    set_arch() {
      case "$(uname -m)" in
        x86_64)
          ARCH=amd64
          ;;
        aarch64)
          ARCH=arm64
          ;;
        *)
          ARCH="$(uname -m)"
          ;;
      esac
      status echo "Set ARCH to ${ARCH}"
    }

    run_provisioner() {
      status $@ && ret=$? || ret=$?
      if [[ "${ret}" != 0 ]]; then
        if [[ "${ret}" == 3 ]]; then
          status echo "Rebooting..."
          sleep 15 || :
          reboot
          while true; do sleep 1; done
        fi
        echo "BuildFailed: exiting due to errors"
        # Under normal circumstances, Daisy will delete the VM once it sees
        # "BuildFailed". But sometimes Daisy will die unexpectedly, so we want
        # to shutdown ourselves to conserve resources. Let's give Daisy 5
        # minutes to capture logs and delete the VM. If Daisy doesn't do that in
        # 5 minutes, let's shut ourselves down.
        sleep 300 || :
        shutdown -h now
        while true; do sleep 1; done
      else
        echo "BuildSucceeded: Build completed with no errors. Shutting down..."
        # Once we shut down, the serial logs will be gone. We need to give Daisy
        # time to capture the serial logs. Once Daisy is done capturing the
        # serial logs, it will add the "DaisyEnd" metadata key. Let's wait for
        # that key to appear (and shutdown anyway after 5 minutes).
        /mnt/disks/cidata/metadata_watcher_${ARCH} DaisyEnd
        umount /mnt/disks/cidata
        umount /mnt/disks/scratch || :
        shutdown -h now
        while true; do sleep 1; done
      fi
    }

    main() {
      status history -c
      set_arch
      if [[ -e /dev/disk/by-label/SCRATCH ]]; then
        setup_scratch_disk
      fi
      status mkdir -p /mnt/disks/cidata
      status mount /dev/disk/by-label/CIDATA /mnt/disks/cidata
      if [[ ! -d /var/lib/.cos-customizer ]]; then
        run_provisioner /mnt/disks/cidata/provisioner_${ARCH} run --config=/mnt/disks/cidata/config.json
      else
        run_provisioner /mnt/disks/cidata/provisioner_${ARCH} resume
      fi
    }

    main
- path: /etc/systemd/system/customizer@.service
  permissions: 0644
  content: |
    [Unit]
    Description=Container-Optimized OS Customization Service
    Wants=network-online.target gcr-online.target docker.service
    After=network-online.target gcr-online.target docker.service

    [Service]
    Type=oneshot
    RemainAfterExit=yes
    User=root
    ExecStart=/bin/bash /tmp/startup.sh
    ExecStopPost=/bin/bash -c 'rm /etc/systemd/system/customizer@.service'
    StandardOutput=tty
    StandardError=tty
    TTYPath=%I

runcmd:
- echo "Starting startup service..."
- systemctl daemon-reload
- |
  if [[ "$(uname -m)" == "aarch64" ]]; then
    systemctl --no-block start customizer@-dev-ttyAMA2.service
  else
    systemctl --no-block start customizer@-dev-ttyS2.service
  fi