container_helper.py

# Copyright 2016 Google Inc. All rights reserved.
#
# 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.

"""Helper methods for working with containers in config."""

USER_DATA_TEMPLATE = \
"""\
#cloud-config

users:
- name: cloudservice
  uid: 2000

write_files:
- path: /etc/systemd/system/container.service
  permissions: 0644
  owner: root
  content: |
    [Unit]
    Description=service that runs the container

    [Service]
    Restart=always
    RestartSec=5
    PermissionsStartOnly=true
    Environment="HOME=/home/cloudservice"
    ExecStartPre=/usr/share/google/dockercfg_update.sh
    ExecStart=/usr/bin/docker run --rm -u 2000 --name={name} {env} {port} {image}
    ExecStop=/usr/bin/docker stop {name}
    ExecStopPost=/usr/bin/docker rm {name}

runcmd:
- systemctl daemon-reload
- systemctl start container.service
"""

def generate_user_data(context):
    """Generates user data given a Template context.

    Args:
    context: Template context, which must contain dockerImage and port
        properties, and an optional dockerEnv property.

    Returns:
    A user data string.
    """

    user_data_parameters = {
        'port': '',
        'env': '',
        'name': context.properties['dockerImage'].split('/')[-1].split('@')[0],
        'image': context.properties['dockerImage']}

    if 'port' in context.properties and context.properties['port']:
        port = context.properties['port']
        user_data_parameters['port'] = '-p {0}:{0}'.format(port)

    if 'dockerEnv' in context.properties:
        docker_env = context.properties['dockerEnv']
        environment_variables = " ".join("-e {0}='{1}'".format(k, v)
                                         for k, v in docker_env.iteritems())
        user_data_parameters['env'] = environment_variables

    return USER_DATA_TEMPLATE.format(**user_data_parameters)

deploy.py

# Copyright 2016 Google Inc. All rights reserved.
#
# 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.

"""Creates autoscaled, network LB IGM running specified docker image."""


def GenerateConfig(context):
    """Generate YAML resource configuration."""

    # Pull the region out of the zone
    region = context.properties['zone'][:context.properties['zone'].rfind('-')]
    name = context.env['name']
    instance_group_manager_name = name + '-igm'
    instance_template_name = name + '-it'

    resources = [
        {
            'name': instance_template_name,
            'type': 'instance_template.py',
            'properties': {
                'port': context.properties['port'] if 'port' in context.properties else None,
                'dockerEnv': context.properties['dockerEnv'] if 'dockerEnv' in context.properties else {},
                'dockerImage': context.properties['dockerImage'],
                'containerImage': context.properties['containerImage'],
                'machineType': context.properties['machineType']
            }},
        {
            'name': instance_group_manager_name,
            'type': 'compute.v1.instanceGroupManager',
            'properties': {
                'zone': context.properties['zone'],
                'targetSize': context.properties['minSize'],
                'baseInstanceName': name,
                'instanceTemplate': '$(ref.' + instance_template_name + '.selfLink)'
            }
        },
        {
            'name': name + '-as',
            'type': 'compute.v1.autoscaler',
            'properties': {
                'zone': context.properties['zone'],
                'target': '$(ref.' + name + '-igm.selfLink)',
                'autoscalingPolicy': {
                    'minNumReplicas': context.properties['minSize'],
                    'maxNumReplicas': context.properties['maxSize'],
                    'coolDownPeriodSec': context.properties['coolDownPeriod'],
                    'cpuUtilization': {
                        'utilizationTarget': context.properties['utilizationTarget']
                    }
                }
            }
        }
    ]

    return {'resources': resources}

deploy.yaml

imports:
- path: deploy.py
- path: instance_template.py
- path: container_helper.py

resources:
- name: match-preprod-ad
  type: deploy.py
  properties:
    zone: us-central1-f
    containerImage: cos-stable-58-9334-62-0
    dockerImage: gcr.io/<your-project-id>/<your-image>@sha256:<sha256>
    minSize: 1
    maxSize: 2
    utilizationTarget: .9
    coolDownPeriod: 300
    machineType: f1-micro

instance_template.py

# Copyright 2016 Google Inc. All rights reserved.
#
# 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.

"""Creates a Container VM with the provided Container manifest."""

from container_helper import generate_user_data


def GenerateConfig(context):
    # TODO: remove useless scopes
    scopes = [
        "https://www.googleapis.com/auth/devstorage.read_only",
        "https://www.googleapis.com/auth/logging.write",
        "https://www.googleapis.com/auth/monitoring.write",
        "https://www.googleapis.com/auth/servicecontrol",
        "https://www.googleapis.com/auth/service.management.readonly",
        "https://www.googleapis.com/auth/trace.append"
    ]

    image = 'projects/cos-cloud/global/images/' + \
    context.properties['containerImage']

    default_network = ''.join(
    ['https://www.googleapis.com/compute/v1/projects/', context.env['project'],
     '/global/networks/default'])

    instance_template = {
        'name': context.env['name'],
        'type': 'compute.v1.instanceTemplate',
        'properties': {
            'properties': {
                'metadata': {
                    'items': [
                        {
                            'key': 'user-data',
                            'value': generate_user_data(context)
                        },
                        {
                            'key': 'instance-group-name',
                            'value': context.env['name'] + '-igm'
                        }]},

                'machineType': context.properties['machineType'],

                'disks': [
                    {
                        'deviceName': 'boot',
                        'boot': True,
                        'autoDelete': True,
                        'mode': 'READ_WRITE',
                        'type': 'PERSISTENT',
                        'initializeParams':
                            {
                                'sourceImage': image,
                                'distName': context.env['name'] + '-disk'
                            }}],

                'networkInterfaces': [
                    {
                        'accessConfigs': [
                            {
                                'name': 'external-nat',
                                'type': 'ONE_TO_ONE_NAT'
                            }],
                        'network': default_network}],

                'scheduling': {'preemptible': True},

                'serviceAccounts': [
                    {
                    # TODO: set your @developer.gserviceaccount.com account.
                    "email": "",
                    "scopes": scopes}],
            }
        }
    }

    return {'resources': [instance_template]}