public/release/Get-PSTSReleaseDefinition.ps1

function Get-PSTSReleaseDefinition
{
    param(
        [Parameter(ParameterSetName="set1")][string] $project,
        [Parameter(ParameterSetName="set1")][string] $releaseId = $null,
        [Parameter(ParameterSetName="set2")][string] $inFile
    )

    process {

        if ($PSCmdlet.ParameterSetName -eq "set1" ) {

            if ($null -ne $releaseId ) {
                $content = `
                _PSTSAPI `
                    -subDomain "vsrm" `
                    -project $project `
                    -resource "Release/Definitions" `
                    -apiVersion "api-version=5.1" `
                    -id $releaseId `
                    -method "GET"
                    
            return $content

            }
            else {
                $content = `
                _PSTSAPI `
                    -subDomain "vsrm" `
                    -project $project `
                    -resource "Release/Definitions" `
                    -apiVersion "api-version=5.1" `
                    -method "GET"
            }

            return [ReleaseDefinition[]]$content.value
        }
        else {
            return $(`
            Get-Content $inFile | `
            Out-String) | `
            ConvertFrom-Json
        }
    }
}