Azure DevOps YAML流水线动态设置部署环境变量失效求助

尝试编写Azure DevOps YAML流水线，计划在前序作业中动态设置部署环境，但变量未正常生效。执行后echo Hello, $(environmentName)!仅输出Hello, !。

概念示例代码：

pool:
  vmImage: 'ubuntu-latest'

stages:
- stage: SetVariable
  jobs:
  - job: SetVariableJob
    steps:
    - script: |
        echo "##vso[task.setvariable variable=environmentName;isOutput=true]TestEnvironmentName"
      name: setvarStep

- stage: Deploy
  dependsOn: SetVariable
  variables:
    environmentName: $[ dependencies.SetVariable.outputs['SetVariableJob.setvarStep.environmentName'] ]
  jobs:
  - deployment: DeployWeb
    environment: $(environmentName)
    strategy:
      runOnce:
        deploy:
          steps:
          - script: echo Hello, $(environmentName)!

问题核心有两点：跨阶段变量引用语法错误，以及部署作业的environment字段不支持运行时变量引用，需使用编译时模板表达式。

1. 修正跨阶段变量引用语法
   跨阶段引用输出变量必须使用stageDependencies而非dependencies，正确写法为：

   $[ stageDependencies.SetVariable.SetVariableJob.outputs['setvarStep.environmentName'] ]
   

2. 调整部署作业的环境字段赋值方式
   部署作业的environment属于编译时属性，无法直接用$(environmentName)这种运行时变量引用，需直接使用模板表达式引用输出变量，或通过阶段变量中转后用模板表达式调用。

3. 完整修正后的流水线代码
   方案一：直接在environment字段引用输出变量

   pool:
     vmImage: 'ubuntu-latest'
   
   stages:
   - stage: SetVariable
     jobs:
     - job: SetVariableJob
       steps:
       - script: |
           echo "##vso[task.setvariable variable=environmentName;isOutput=true]TestEnvironmentName"
         name: setvarStep
   
   - stage: Deploy
     dependsOn: SetVariable
     jobs:
     - deployment: DeployWeb
       environment: $[ stageDependencies.SetVariable.SetVariableJob.outputs['setvarStep.environmentName'] ]
       strategy:
         runOnce:
           deploy:
             steps:
             - script: echo Hello, $[ stageDependencies.SetVariable.SetVariableJob.outputs['setvarStep.environmentName'] ]!
   

   方案二：通过阶段变量中转，方便步骤中重复使用

   pool:
     vmImage: 'ubuntu-latest'
   
   stages:
   - stage: SetVariable
     jobs:
     - job: SetVariableJob
       steps:
       - script: |
           echo "##vso[task.setvariable variable=environmentName;isOutput=true]TestEnvironmentName"
         name: setvarStep
   
   - stage: Deploy
     dependsOn: SetVariable
     variables:
       environmentName: $[ stageDependencies.SetVariable.SetVariableJob.outputs['setvarStep.environmentName'] ]
     jobs:
     - deployment: DeployWeb
       environment: $[ variables.environmentName ]
       strategy:
         runOnce:
           deploy:
             steps:
             - script: echo Hello, $(environmentName)!
   

内容的提问来源于stack exchange，提问作者codechurn