How do I pass information from one step in a TFS 2017 build to a later Copy Files step

Question

OK - I've read all about environment variables and how they can't be set and read by the same process (even this can't be read by a later step in the build):

Environment.SetEnvironmentVariable("Major_Build_Number", BaseReleaseNumber, EnvironmentVariableTarget.Machine)

So has anyone come up with a simple way to pass along info from one build step to another? In my first step I determine the build number (this is a fairly complex process believe it or not) and I need to pass that build number to the last build step (which is a Copy Files step) so that it can copy the build into a folder that's named with the build number. I've tried setting an environment variable, but unfortunately that can't be set and read from the same session. There's gotta be a simple way to do this. Yes I could write a PS or batch script to do it and store the value in a file or the registry, but I would prefer to use the Copy Files task and I can't figure out how to pass that value along.

I tried defining a variable in the build definition and storing the value there but I can't seem to change that value after it's set in the build definition.

BTW, this is an on-premises installation - not VSTS.

Anyone have any ideas?

Thanks Andy for your response. So I tried this in SetBuildNumberENVVar.ps1

param([Int32]$MajorBuildNumber=0,[Int32]$MinorBuildNumber=0)

Write-Host "##vso[task.setvariable variable=MajorBuildNumber]$MajorBuildNumber"
Write-Host "##vso[task.setvariable variable=MinorBuildNumber]$MinorBuildNumber"

I then run it from the command line:

c:\powershell .\SetBuildNumberENVVar.ps1 23 45

and then try to echo the variable:

echo %MajorBuildNumber%
%MajorBuildNumber%

and as you can see it doesn't appear to work. I tried this from a C# script:

int.TryParse("$(MajorBuildNumber)", out mbn);

and mbn = 0 after this runs.

Any idea what I'm doing wrong?

Answer 1

Generally you can use the predefined variale $(Build.BuildNumber) to name the folder, it can be used directly in entire build process. See Predefined variables for details.

If you customed the build number variable as you said : "I determine the build number (this is a fairly complex process believe it or not)". Then you can pass the value with the Logging Command: ##vso[task.setvariable]value:

1. Add a PowserShell task in you build definition

2. Copy and paste below script and save it as *.ps1 file

   $value= "The value of the build number here" Write-Host "##vso[task.setvariable variable=BuildNumber]$value"

3. Check in the PS file, then run the PS file in PowerShell task

After that, you can use the variable $BuildNumber directly in any tasks behind the PowserShell task.

You can reference my answer in another similar thread : Custom TFS Enviroment Variable doesn't read $(Date)

---

UPDATE:

You need to run the PowerShell script in TFS build process.

See below example:

I created two PS scripts, one to set the variables to pass the value, another to use the variables to create a folder named with the passed values:

PS1: PassBuildNumber

param([Int32]$MajorBuildNumber=0,[Int32]$MinorBuildNumber=0)

Write-Host "##vso[task.setvariable variable=MajorBuildNumber]$MajorBuildNumber"
Write-Host "##vso[task.setvariable variable=MinorBuildNumber]$MinorBuildNumber"

PS2 : Use the variables

Write-Host "The Major build number is:" $env:MajorBuildNumber
Write-Host "The Minor build number is:" $env:MinorBuildNumber

$foldername = $env:MajorBuildNumber + "." + $env:MinorBuildNumber
Write-Host "foldername:" $foldername

$path = "\\myshare\DirA\$foldername"
Write-Host "path:" $path

New-Item -Path $path -ItemType directory # Create a folder
Write-Host "##vso[task.setvariable variable=path]$path"  # Set path as a variable to be used in Copy Task

Then you can use Copy Files task to copy files to that folder.