部署网络负载平衡日志应用

在本教程中，您将部署一个示例日志应用，该应用使用 Node.js 作为其前端，并使用 MySQL 作为其后端。在本教程结束时，您的部署具有以下资源：

如果您刚接触 Deployment Manager，请参阅快速入门或分步指南教程。

准备工作

• 如果要使用本指南中的命令行示例，请安装 “gcloud” 命令行工具。
• 如果希望使用本指南中的 API 示例，请设置 API 访问权限。
• 阅读 Compute Engine 网络负载均衡概述。
• 阅读 Docker 容器概览。

创建资源模板

此示例启动了包含各种 Google Cloud 资源的部署。首先，您要创建分别定义这些资源的模板。随后，您将在最终配置中调用这些模板。您的部署包含以下资源：

• 托管应用程序 MySQL 数据库的 Compute Engine实例。
• 将 Docker 映像用于 Node.js 应用程序的前端实例模板。
• 使用实例模板创建两个前端实例的托管实例组。
• 根据传入流量启动或停止其他前端实例的自动缩放器。
• 检查前端实例是否可用于执行工作的健康检查。
• 包含转发规则的网络负载均衡器。
• 托管实例组的目标池。

为 MySQL 后端创建模板

此应用的后端是一个运行 MySQL Docker 容器的单个 Compute Engine 实例。container_vm.py 模板定义了可以运行 Docker 容器的 Compute Engine 实例。要确保模板采用正确的结构并包含所有必要属性，还需要一个架构文件。

复制下面的模板，或从 GitHub 代码库下载：

# 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 GenerateManifest

COMPUTE_URL_BASE = 'https://www.googleapis.com/compute/v1/'

def GlobalComputeUrl(project, collection, name):
  return ''.join([COMPUTE_URL_BASE, 'projects/', project,
                  '/global/', collection, '/', name])

def ZonalComputeUrl(project, zone, collection, name):
  return ''.join([COMPUTE_URL_BASE, 'projects/', project,
                  '/zones/', zone, '/', collection, '/', name])

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

  base_name = context.env['name']

  # Properties for the container-based instance.
  instance = {
      'zone': context.properties['zone'],
      'machineType': ZonalComputeUrl(context.env['project'],
                                     context.properties['zone'],
                                     'machineTypes',
                                     'f1-micro'),
      'metadata': {
          'items': [{
              'key': 'gce-container-declaration',
              'value': GenerateManifest(context)
              }]
          },
      'disks': [{
          'deviceName': 'boot',
          'type': 'PERSISTENT',
          'autoDelete': True,
          'boot': True,
          'initializeParams': {
              'diskName': base_name + '-disk',
              'sourceImage': GlobalComputeUrl('cos-cloud',
                                              'images',
                                              context.properties[
                                                  'containerImage'])
              },
          }],
      'networkInterfaces': [{
          'accessConfigs': [{
              'name': 'external-nat',
              'type': 'ONE_TO_ONE_NAT'
              }],
          'network': GlobalComputeUrl(context.env['project'],
                                      'networks',
                                      'default')
          }],
        'serviceAccounts': [{
            'email': 'default',
            'scopes': ['https://www.googleapis.com/auth/logging.write']
            }]
      }

  # Resources to return.
  resources = {
      'resources': [{
          'name': base_name,
          'type': 'compute.v1.instance',
          'properties': instance
          }]
      }

  return resources

下载模板的架构文件。

该模板有一些未定义的属性（例如 containerImage）将在以后的模板中定义。

您在 Compute Engine 实例上使用容器映像时，还需要提供描述要使用的容器映像的清单文件。创建一个名为 container_helper.py 的辅助方法，用于动态定义容器清单：

# 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."""

import six
import yaml

def GenerateManifest(context):
  """Generates a Container Manifest given a Template context.

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

  Returns:
    A Container Manifest as a YAML string.
  """
  env_list = []
  if 'dockerEnv' in context.properties:
    for key, value in six.iteritems(context.properties['dockerEnv']):
      env_list.append({'name': key, 'value': str(value)})

  manifest = {
      'apiVersion': 'v1',
      'kind': 'Pod',
      'metadata': {
          'name': str(context.env['name'])
          },
      'spec': {
          'containers': [{
              'name': str(context.env['name']),
              'image': context.properties['dockerImage'],
              'ports': [{
                  'hostPort': context.properties['port'],
                  'containerPort': context.properties['port']
                  }],
              }]
          }
      }

  if env_list:
    manifest['spec']['containers'][0]['env'] = env_list

  return yaml.dump(manifest, default_flow_style=False)

为 Node.js 前端创建模板

应用的前端运行 Node.js，并允许用户将消息发布到网页上。在一组虚拟机实例上运行的前端，由自动调节程序和负载均衡器提供支持。要创建前端模板，请按照以下说明操作。

1. 创建实例模板资源。

   您需要实例模板来创建托管实例组，这是您作为单个实体控制的一组相同的虚拟机 (VM) 实例。

   创建名为 container_instance_template.py 的文件，然后下载模板的架构：

   # 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 GenerateManifest
   
   def GenerateConfig(context):
     """Generates configuration."""
   
     image = ''.join(['https://www.googleapis.com/compute/v1/',
                      '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'] + '-it',
         'type': 'compute.v1.instanceTemplate',
         'properties': {
             'properties': {
                 'metadata': {
                     'items': [{
                         'key': 'gce-container-declaration',
                         'value': GenerateManifest(context)
                         }]
                     },
                 'machineType': 'f1-micro',
                 'disks': [{
                     'deviceName': 'boot',
                     'boot': True,
                     'autoDelete': True,
                     'mode': 'READ_WRITE',
                     'type': 'PERSISTENT',
                     'initializeParams': {'sourceImage': image}
                     }],
                 'networkInterfaces': [{
                     'accessConfigs': [{
                         'name': 'external-nat',
                         'type': 'ONE_TO_ONE_NAT'
                         }],
                     'network': default_network
                     }],
                   'serviceAccounts': [{
                       'email': 'default',
                       'scopes': ['https://www.googleapis.com/auth/logging.write']
                       }]
                 }
             }
         }
   
     outputs = [{'name': 'instanceTemplateSelfLink',
                 'value': '$(ref.' + instance_template['name'] + '.selfLink)'}]
   
     return {'resources': [instance_template], 'outputs': outputs}
   

   下载模板的架构文件。

2. 创建自动调节程序、托管实例组和负载均衡器。

   下一步，创建使用 container_instance_template.py 模板的另一个模板，并创建其余的前端资源，包括自动调节程序、负载均衡器和托管实例组。

此模板包含以下资源：

1. 使用 container_instance_template.py 模板的实例模板。

2. 使用实例模板的托管实例组以及引用托管实例组的自动调节程序。使用引用确保 Deployment Manager 按特定顺序创建资源。在此情况下，在自动调节程序之前创建托管实例组。

3. 包含以下资源的网络负载均衡器：

   • 向互联网公开单个外部 IP 地址的转发规则。
   • 包含您之前创建的托管实例组的目标池。
   • 要附加到目标池的健康检查。

创建名为 frontend.py 的文件，然后下载模板的架构：

# 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']

  resources = [{
      'name': name,
      'type': 'container_instance_template.py',
      'properties': {
          'port': context.properties['port'],
          'dockerEnv': context.properties['dockerEnv'],
          'dockerImage': context.properties['dockerImage'],
          'containerImage': context.properties['containerImage']
      }
  }, {
      'name': name + '-igm',
      'type': 'compute.v1.instanceGroupManager',
      'properties': {
          'zone': context.properties['zone'],
          'targetSize': context.properties['size'],
          'targetPools': ['$(ref.' + name + '-tp.selfLink)'],
          'baseInstanceName': name + '-instance',
          'instanceTemplate': '$(ref.' + name + '-it.selfLink)'
      }
  }, {
      'name': name + '-as',
      'type': 'compute.v1.autoscaler',
      'properties': {
          'zone': context.properties['zone'],
          'target': '$(ref.' + name + '-igm.selfLink)',
          'autoscalingPolicy': {
              'maxNumReplicas': context.properties['maxSize']
          }
      }
  }, {
      'name': name + '-hc',
      'type': 'compute.v1.httpHealthCheck',
      'properties': {
          'port': context.properties['port'],
          'requestPath': '/_ah/health'
      }
  }, {
      'name': name + '-tp',
      'type': 'compute.v1.targetPool',
      'properties': {
          'region': region,
          'healthChecks': ['$(ref.' + name + '-hc.selfLink)']
      }
  }, {
      'name': name + '-lb',
      'type': 'compute.v1.forwardingRule',
      'properties': {
          'region': region,
          'portRange': context.properties['port'],
          'target': '$(ref.' + name + '-tp.selfLink)'
      }
  }]
  return {'resources': resources}

下载模板的架构文件。

创建统一模板

最后，创建一个结合后端和前端模板的模板。创建名为 nodejs.py 且包含以下内容的文件：

# 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.

"""Create nodejs template with the back-end and front-end templates."""

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

  backend = context.env['deployment'] + '-backend'
  frontend = context.env['deployment'] + '-frontend'
  firewall = context.env['deployment'] + '-application-fw'
  application_port = 8080
  mysql_port = 3306
  resources = [{
      'name': backend,
      'type': 'container_vm.py',
      'properties': {
          'zone': context.properties['zone'],
          'dockerImage': 'gcr.io/qwiklabs-resources/mysql',
          'containerImage': 'family/cos-stable',
          'port': mysql_port,
          'dockerEnv': {
              'MYSQL_ROOT_PASSWORD': 'mypassword'
          }
      }
  }, {
      'name': frontend,
      'type': 'frontend.py',
      'properties': {
          'zone': context.properties['zone'],
          'dockerImage': 'gcr.io/qwiklabs-resources/nodejsservice',
          'port': application_port,
          # Define the variables that are exposed to container as env variables.
          'dockerEnv': {
              'SEVEN_SERVICE_MYSQL_PORT': mysql_port,
              'SEVEN_SERVICE_PROXY_HOST': '$(ref.' + backend
                                          + '.networkInterfaces[0].networkIP)'
          },
          # If left out will default to 1
          'size': 2,
          # If left out will default to 1
          'maxSize': 20
      }
  }, {
      'name': firewall,
      'type': 'compute.v1.firewall',
      'properties': {
          'allowed': [{
              'IPProtocol': 'TCP',
              'ports': [application_port]
          }],
          'sourceRanges': ['0.0.0.0/0']
      }
  }]
  return {'resources': resources}

下载模板的架构文件。

请注意，应用的前端名为 env["deployment"]-frontend，并且您的后端也采用相似的名称。部署应用时，Deployment Manager 会自动将 env["deployment"] 替换为部署名称。

创建配置

准备好所有模板后，您可以创建用于部署资源的配置。创建名为 nodejs.yaml 且包含以下内容的配置文件：

# 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.

# Launches an autoscaled, load-balanced frontend running nodejs for serving
# traffic. Also launches a single MySQL container instance, wires the two
# together using references, and passes them as env variables to the underlying
# frontend Docker containers.
imports:
- path: nodejs.py

resources:
- name: nodejs
  type: nodejs.py
  properties:
    zone: ZONE_TO_RUN

将 ZONE_TO_RUN 替换为您需要从中获取资源的地区，例如 us-central1-a。

部署资源

现在，部署您的资源。使用 Google Cloud CLI 运行以下命令：

gcloud deployment-manager deployments create advanced-configuration --config nodejs.yaml

部署完成后，Deployment Manager 将显示已创建资源的摘要，类似以下所示：

Waiting for create operation-1468522101491-5379cf2344539-5961abe8-a500190c...done.
Create operation operation-1468522101491-5379cf2344539-5961abe8-a500190c completed successfully.
NAME                                   TYPE                             STATE      ERRORS
advanced-configuration-application-fw  compute.v1.firewall              COMPLETED  []
advanced-configuration-backend         compute.v1.instance              COMPLETED  []
advanced-configuration-frontend-as     compute.v1.autoscaler            COMPLETED  []
advanced-configuration-frontend-hc     compute.v1.httpHealthCheck       COMPLETED  []
advanced-configuration-frontend-igm    compute.v1.instanceGroupManager  COMPLETED  []
advanced-configuration-frontend-it     compute.v1.instanceTemplate      COMPLETED  []
advanced-configuration-frontend-lb     compute.v1.forwardingRule        COMPLETED  []
advanced-configuration-frontend-tp     compute.v1.targetPool            COMPLETED  []

测试应用

要测试应用，请先通过查询转发规则获取传送流量的外部 IP 地址：

$ gcloud compute forwarding-rules describe advanced-configuration-frontend-lb --region us-central1
IPAddress: 104.154.81.44
IPProtocol: TCP
creationTimestamp: '2016-07-14T11:48:37.228-07:00'
description: ''
id: '9033201246750269546'
kind: compute#forwardingRule
name: advanced-configuration-frontend-lb
portRange: 8080-8080
region: https://www.googleapis.com/compute/v1/projects/myproject/regions/us-central1
selfLink: https://www.googleapis.com/compute/v1/projects/myproject/regions/us-central1/forwardingRules/advanced-configuration-frontend-lb
target: https://www.googleapis.com/compute/v1/projects/myproject/regions/us-central1/targetPools/advanced-configuration-frontend-tp

在此示例中，外部 IP 为 104.154.81.44。

接下来，在浏览器中，通过端口 8080 访问外部 IP 地址。例如，如果您的外部 IP 地址是 104.154.81.44，则网址为：

http://104.154.81.44:8080

系统应该会显示一个空白页面。下一步，在页面发布消息。转到以下网址：

http://104.154.81.44:8080?msg=hellothere!

系统会向您发送确认消息，告知您消息已添加至页面。返回主网址，这时，该页面应显示以下消息：

hellothere!

您现在有一个已部署的应用，可以记录发送给它的消息。

后续步骤

完成此示例后，您可以：

• 通过用您自己的 Docker 容器部署实例来构建此示例。 如果要修改本教程中使用的 Docker 容器，请修改 GitHub 代码库中的 Dockerfile。
• 请参阅 Deployment Manager GitHub 代码库中的更多示例部署。
• 详细了解模板和部署。