Azure DevOps部署ARM模板时int参数被转为字符串的问题

问题描述 #

部署Data Factory ARM模板时，ARM模板中定义了一个int类型的全局参数，但从Azure DevOps变量组传递覆盖参数时，变量总是被自动转成字符串类型，导致流水线因类型不匹配报错。

当前部署任务的YAML配置：

- task: AzureResourceManagerTemplateDeployment@3
  displayName: ARM Template Deployment
  inputs:
    azureResourceManagerConnection: 
    subscriptionId: 
    resourceGroupName: 
    location:
    csmFile:
    csmParametersFile:
    overrideParameters: >
      -factoryName ${{ parameters.dataFactoryName }}
      ${{ parameters.overrideParameters }}

变量组中的变量配置：

已尝试两种无效方法：

无效方法1：直接引用变量组变量 #

variables:
  - group: test-group

...

jobs:
  - template: datafactory/create-release.yml@templates
    parameters:
      dataFactoryName: asdfasdf
      overrideParameters: >
        -default_properties_LogoAssetId_value $(default_properties_LogoAssetId_value_Stage)

无效方法2：尝试用ARM函数强制转换 #

variables:
  - group: test-group

...

jobs:
  - template: datafactory/create-release.yml@templates
    parameters:
      dataFactoryName: asdfasdf
      overrideParameters: >
        -default_properties_LogoAssetId_value "[int(parameters($(default_properties_LogoAssetId_value_Stage)))]"

补充信息：datafactory/create-release.yml模板中overrideParameters被定义为字符串类型，不清楚如何同时传递字符串和int类型的覆盖参数：

parameters:
  - name: overrideParameters
    type: string

jobs:
  - deployment: Deploy
    displayName: Deploy ARM Template
    environment: Prod
    pool:
      vmImage: ubuntu-latest
    strategy:
      runOnce:
        deploy:
          steps:
            - template: steps/step-arm-template-deploy.yml
              parameters:
                subscriptionId: ${{ parameters.subscriptionId }}
                targetResourceGroupName: ${{ parameters.targetResourceGroupName }}
                targetDataFactorylocation: ${{ parameters.targetDataFactorylocation }}
                targetDataFactoryName: ${{ parameters.targetDataFactoryName }}
                overrideParameters: ${{ parameters.overrideParameters }}

解决方案 #

方法1：用Azure DevOps运行时表达式强制转换类型 #

Azure DevOps变量组的变量默认都是字符串类型，可通过运行时表达式$[int()]显式转换为数值类型后传递：

variables:
  - group: test-group

...

jobs:
  - template: datafactory/create-release.yml@templates
    parameters:
      dataFactoryName: asdfasdf
      overrideParameters: >
        -default_properties_LogoAssetId_value $[int('$(default_properties_LogoAssetId_value_Stage)')]

这里用单引号包裹变量是因为变量替换后是字符串形式的数字，int()函数需要接收字符串输入完成转换。

方法2：改用对象类型参数传递多类型参数 #

如果需要同时传递多种类型的覆盖参数，建议修改模板参数定义为对象类型，避免字符串拼接的类型问题：

1. 修改datafactory/create-release.yml的参数定义：

parameters:
  - name: dataFactoryName
    type: string
  - name: subscriptionId
    type: string
  - name: targetResourceGroupName
    type: string
  - name: targetDataFactorylocation
    type: string
  - name: targetDataFactoryName
    type: string
  - name: overrideParams
    type: object
    default: {}

jobs:
  - deployment: Deploy
    displayName: Deploy ARM Template
    environment: Prod
    pool:
      vmImage: ubuntu-latest
    strategy:
      runOnce:
        deploy:
          steps:
            - template: steps/step-arm-template-deploy.yml
              parameters:
                subscriptionId: ${{ parameters.subscriptionId }}
                targetResourceGroupName: ${{ parameters.targetResourceGroupName }}
                targetDataFactorylocation: ${{ parameters.targetDataFactorylocation }}
                targetDataFactoryName: ${{ parameters.targetDataFactoryName }}
                overrideParameters: >
                  -factoryName ${{ parameters.dataFactoryName }}
                  ${{ each param in parameters.overrideParams }}:
                    -${{ param.key }} ${{ param.value }}

2. 调用模板时传递对象参数，按需转换类型：

variables:
  - group: test-group

...

jobs:
  - template: datafactory/create-release.yml@templates
    parameters:
      dataFactoryName: asdfasdf
      subscriptionId: 'xxx'
      targetResourceGroupName: 'xxx'
      targetDataFactorylocation: 'xxx'
      targetDataFactoryName: 'xxx'
      overrideParams:
        default_properties_LogoAssetId_value: $[int('$(default_properties_LogoAssetId_value_Stage)')]
        # 字符串类型参数直接传递即可
        anotherStringParam: '$(someStringVariable)'

方法3：在ARM参数文件中处理类型转换 #

如果可以修改ARM参数文件，直接在参数文件中使用int()函数完成类型转换，无需在流水线中处理：

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "default_properties_LogoAssetId_value": {
      "value": "[int('$(default_properties_LogoAssetId_value_Stage)')]"
    }
  }
}

部署时无需在overrideParameters中传递该参数，ARM模板会自动完成类型转换。

内容的提问来源于stack exchange，提问作者Kevvv