Capturing build date in deployment pipleine - azure-devops

Question

I'm trying to capture the build date of an artifact to be logged elsewhere. Join me on my convoluted journey to solve this.
I know we have these handy variables
$(Build.SourceVersion)
$(Build.BuildNumber)
EDIT: These are not as handy as I thought. These are just the identifers for the deploy pipeline, not the original build pipeline that generated the artefact. So I can repeatedly deploy the same build / artefact, and these numbers will continue to increment, having no relevance to what I built - I'm not interested in that.
But there is no build date. I know it can be derived from the BuildNumber but it seems over the top to call a REST API to get that info.
So in my build pipeline I am writing Get-Date to a file then publishing that as an artefact
- powershell: (Get-Date).ToString("yyyy-MM-dd HH:mm:ss") | Out-File -FilePath $(Build.ArtifactStagingDirectory)\BuildDt.txt
Then I pick that up in the deploy pipeline and save to a variable using the kludgy Write-Host method
- stage: DownloadDBArtifacts
displayName: Download DB Artifacts
dependsOn: []
jobs:
- job: GetArtefacts
displayName: Get Artefacts
steps:
- download: DBBuild
- task: PowerShell#2
displayName: Get Build timestamp
name: GetBuildDt
inputs:
targetType: inline
script: |
$BuildDt = Get-Content -Path $(Pipeline.Workspace)\DBBuild\drop\BuildDt.txt
Write-Host "##vso[task.setvariable variable=BuildDt;isoutput=true]$BuildDt"
Write-Host "##[debug]Artifact Creation Date: $BuildDt"
This is done in stage DownloadDBArtifacts
Now I need to use it in a later stage, that is also in a child YAML template
I beleive this is the syntax for extracting the variable:
stageDependencies.DownloadDBArtifacts.GetArtefacts.outputs['GetBuildDt.BuildDt']
I'm having difficulty getting this recognised in later stages. Here is a subsequent stage that tries to capture the value based on examples from here:
https://learn.microsoft.com/en-us/azure/devops/pipelines/process/variables?view=azure-devops&tabs=yaml%2Cbatch#use-outputs-in-a-different-stage
https://learn.microsoft.com/en-us/azure/devops/pipelines/process/expressions?view=azure-devops#job-to-job-dependencies-across-stages
- stage: DeployDBtoTST
displayName: Deploy DB to TST
dependsOn: DownloadDBArtifacts
variables:
- group: vgTST
jobs:
- deployment: DeployDBtoTST
displayName: Deploy DB to TST
environment: TST Environment
variables:
BuildDt: $[ stageDependencies.DownloadDBArtifacts.GetArtefacts.outputs['GetBuildDt.BuildDt'] ]
strategy:
runOnce:
deploy:
steps:
- powershell: |
Write-Host "var: $(BuildDt)"
however the value is not being passed through as the final powershell step just produces this output:
var:

Answer 1

Capturing build date in deployment pipleine
I could reproduce this issue with your YAML sample.
To resolve this issue, please update your DownloadDBArtifacts by following code:
- stage: DownloadDBArtifacts
displayName: Download DB Artifacts
dependsOn: []
jobs:
- job: GetArtefacts
displayName: Get Artefacts
steps:
- download: DBBuild
- task: InlinePowershell#1
displayName: 'Get Artefacts'
inputs:
Script: |
$BuildDt = Get-Content -Path $(Pipeline.Workspace)\DBBuild\drop\BuildDt.txt
Write-Host "##vso[task.setvariable variable=BuildDt;isOutput=true]$BuildDt"
name: GetBuildDt
The test result:
Update:
Sorry, I tried changing the DownloadDBArtifacts as you mentioned above
andit made no difference.
You have a slight letter error in your code that is causing the issue.
One is name: GetBuiltDt and another is outputs['GetBuildDt.BuildDt'] ]. The Built should be Build：