azure - 将dependsOn 设置为上一阶段，而不对Azure Pipelines 中的值进行硬编码

Question

使用 Azure Pipelines，如何将 dependsOn 设置为前一阶段而不对值进行硬编码？

我可以使用某种预定义变量吗？我只看到了当前阶段，没有看到之前的阶段。

我的管道正在执行 Terraform 部署。第一个(构建)阶段为每个环境并行运行 terraform plan，然后使用该计划文件运行 terraform apply 的(部署)阶段将使用该计划依次在每个环境中。

我在计划(构建)和应用(部署)阶段使用两个不同的模板。我目前正在使用参数来指定 dependsOn 列表值，我需要在其中明确指定所有计划(构建)阶段，但是对于应用(部署)阶段，我希望参数的默认值类似 $(Build.PreviousStage) 的内容，使其更加优雅。

# azure-pipelines.yml

# LINES REMOVED #

stages:
  # Terraform Plan (DevTest)
  - template: templates/plan.yml
    parameters:
      az_service_connection: DevTest-Terraform
      environment: DevTest

  # Terraform Plan (Stage)
  - template: templates/plan.yml
    parameters:
      az_service_connection: Stage-Terraform
      environment: Stage

  # Terraform Plan (Prod)
  - template: templates/plan.yml
    parameters:
      az_service_connection: Prod-Terraform
      environment: Prod

  # Terraform Deploy (DevTest)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: DevTest-Terraform
      depends_on:
        - DevTest_Plan
        - Stage_Plan
        - Prod_Plan
      environment: DevTest

  # Terraform Deploy (Stage)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: Stage-Terraform
      depends_on:
        - DevTest_Deploy
      environment: Stage

  # Terraform Deploy (Prod)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: Prod-Terraform
      depends_on:
        - Stage_Deploy
      environment: Prod

# ./templates/deploy.yml

parameters:
  - name: az_service_connection
    type: string
  - name: depends_on
    type: object
  - name: environment
    type: string

stages:
  # Terraform Deploy
  - stage: ${{ parameters.environment }}_Deploy
    displayName: Terraform Deploy (${{ parameters.environment }})
    condition: and(succeeded(), in(variables['Build.Reason'], 'IndividualCI', 'BatchedCI', 'Manual'))
    dependsOn:
      ${{ parameters.depends_on }}

# LINES REMOVED #

Answer 1

通过 if 条件检查 depends_on 参数是否为空，同时还将参数默认值设置为“”，这使我能够解决此问题，从而允许我设置 depends_on 参数用于第一个 DEV 部署阶段，而不为其他阶段设置。

正如 @Krzysztof Madej 在他的回答/评论中所述，不存在这样的变量来设置 dependsOn 的前一阶段，但如果未设置，将自动依赖于前一阶段。

# azure-pipelines.yml

# LINES REMOVED #

stages:
  # Terraform Plan (DevTest)
  - template: templates/plan.yml
    parameters:
      az_service_connection: DevTest-Terraform
      environment: DevTest

  # Terraform Plan (Stage)
  - template: templates/plan.yml
    parameters:
      az_service_connection: Stage-Terraform
      environment: Stage

  # Terraform Plan (Prod)
  - template: templates/plan.yml
    parameters:
      az_service_connection: Prod-Terraform
      environment: Prod

  # Terraform Deploy (DevTest)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: DevTest-Terraform
      depends_on:
        - DevTest_Plan
        - Stage_Plan
        - Prod_Plan
      environment: DevTest

  # Terraform Deploy (Stage)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: Stage-Terraform
      environment: Stage

  # Terraform Deploy (Prod)
  - template: templates/deploy.yml
    parameters:
      az_service_connection: Prod-Terraform
      environment: Prod

# templates/deploy.yml

parameters:
  - name: az_service_connection
    type: string
  - name: depends_on
    type: object
    default:
  - name: environment
    type: string

stages:
  # Terraform Deploy
  - stage: ${{ parameters.environment }}_Deploy
    displayName: Terraform Deploy (${{ parameters.environment }})
    condition: and(succeeded(), in(variables['Build.Reason'], 'IndividualCI', 'BatchedCI', 'Manual'))
    ${{ if ne(length(parameters.depends_on), 0) }}:
      dependsOn:
        ${{ parameters.depends_on }}