Automate Software Versioning using CI/CD

# file: scripts/modules/version.psm1

Import-Module -Name $(Join-Path $PSScriptRoot “buildkite.psm1”)
Import-Module -Name $(Join-Path $PSScriptRoot “git.psm1”)

function Get-Version {
    return Get-VersionCore “Version”
}

function Get-VersionCore {
    param (
        [Parameter(Mandatory = $true)]
        [string]$Key
    )

    if ($env:BUILDKITE) {
        return Get-BuildkiteMetadata $Key
    }

    # script is running locally
    $metaData = Get-GitVersionMetaData
    if (!$metaData) {
        return $null
    }
   
    return (Get-CalculatedVersions $metaData).$Key
}

function Get-CalculatedVersions {
    param (
        # A custom object storing git version info
        [Parameter(Mandatory = $true)]
        [object] $GitVersionMetaData
    )
   
    $branchName = $env:BUILDKITE_BRANCH ?? $gitVersionMetadata.BranchName
   
    $version = $GitVersionMetaData.MajorMinorPatch
    $build_number = $env:BUILDKITE_BUILD_NUMBER ?? 1
    if ( !(Get-IsMainBranch -BranchName $branchName) –and !(Get-IsHotfixBranch -BranchName $branchName)) {
        $escapedBranchName = $branchName -replace “[^a-zA-Z0-9-]”, “-“
        $version = “$($version).ci-$build_number-$escapedBranchName.$($GitVersionMetaData.ShortSha)”
    }
   
    return @{
        Version = $version
    }
}

function Get-GitVersionMetaData {
    param (
        # gitversion docker image tag
        [String] $GitVersionImageTag = “5.10.3”
    )

    $repoPath = (Get-Item $PSScriptRoot).Parent.Parent.Parent.Parent
    # calculate-version.env file is created under the tmp folder.
    $tmpPath = $(Join-Path $repoPath “tmp”)
    $envFile = $(Join-Path $tmpPath “.env”)

    try {
        # Created the tmp folder
        New-Item -ItemType Directory -Path $tmpPath -Force | Out-Null

        Write-Host “Setting Docker build environment variables in file $envFile.”
        Set-Content -Path $envFile -Value “”
        Add-Content -Path $envFile -Value (“BUILDKITE”)
        Add-Content -Path $envFile -Value (“BUILDKITE_BRANCH”)
        Add-Content -Path $envFile -Value (“BUILDKITE_PULL_REQUEST”)
       
        Write-Host “docker run –rm -v “$($repoPath):/repo” –env-file $envFile gittools/gitversion:$GitVersionImageTag /repo”
               
        $responseJson = $(docker run –rm -v “$($repoPath):/repo” –env-file $envFile gittools/gitversion:$GitVersionImageTag /repo)
       
        $returnCode = $LASTEXITCODE
        if ($returnCode -ne 0) {
            Write-Host “`nGitVersion failed – docker returned non-zero return code of $returnCode.”
            if ($responseJson) {
                Write-Error “`nGitVersion response ‘$responseJson'”
            }
            return $null
        }
   
        return ($responseJson | ConvertFrom-Json)
    }
    catch {
        Write-Error “`n$_.Exception.Message”
        return $null
    }
    finally {
        if (Test-Path -Path $tmpPath) {
            Remove-Item -Path $tmpPath -Force -Recurse
        }
    }
} 

# file: scripts/modules/buildkite.psm1

function Set-BuildkiteMetadata {

    param(
        [Parameter(Mandatory = $true)]
        [string]$Name,

        [Parameter(Mandatory = $true)]
        [string] $Value
    )

    if ($env:BUILDKITE) {
        Write-Host “Setting $($Name)=$($Value)”
        $response = buildkite-agent meta-data set $Name $Value
        $returnCode = $LASTEXITCODE
        if ($returnCode -ne 0) {
            Write-Error “Failed to set Buildkite meta-data for ‘$($Name)=$($Value)’ with return code $($returnCode) and reponse ‘$($response)'”
        }
    }
}
function Get-BuildkiteMetadata {

    param(
        [Parameter(Mandatory = $true)]
        [string]$Name
    )

    if ($env:BUILDKITE) {
        return buildkite-agent meta-data get $Name
    }
    else {
        return $null
    }
}