Call DLBR Common Login secured service from PowerShell

CallDlbrCommonLoginSecuredServiceWithToken.ps1

$ErrorActionPreference = "Stop" 
Set-StrictMode -Version Latest

# config.json example contents:
# {
#    "Audience":  "<some service audience>",
#    "Serviceurl":  "<some service url>",
#    "Idp":  "idp.dlbr.dk",
#    "Serviceaccountusername":  "<some service account username>",
#    "Serviceaccountpassword":  "<some service account password>"
#}
$config = Get-Content ".\config.json" | ConvertFrom-Json

Function Test-Sha256Sum([string]$file, [string]$expectedSha256Hash)
{
    $normalizedExpectedSha256Hash = $expectedSha256Hash.ToLowerInvariant()
	$sha256Hash = (Get-FileHash -Algorithm SHA256 -Path $file).Hash.ToLowerInvariant()    
	if ($sha256Hash -eq $normalizedExpectedSha256Hash)
	{
		return $true
	}
	Write-Warning "File $file has unexpected sha256sum $sha256Hash"
	return $false
}
Function Initialize-ExeFromUrl([string]$filename, [string]$url, [string]$expectedSha256Hash)
{
    $workFolder = "$env:temp\$expectedSha256Hash"
    $outfile = "$workfolder\$filename"
    mkdir -force $workFolder | out-null
    if (Test-Path $outfile)
    {
        if (Test-Sha256Sum $outfile $expectedSha256Hash)
        {
            return $outfile
        }
        Remove-Item $outfile
    }
    Invoke-WebRequest -UseBasicParsing $url -Outfile $outfile
    if (Test-Sha256Sum $outfile $expectedSha256Hash)
    {
		return $outfile
    }
	throw ("Hash mismatch, expected $expectedSha256Hash")
}


Function Initialize-NugetExe
{
    $url = "https://dist.nuget.org/win-x86-commandline/v4.6.2/nuget.exe"
    $expectedHash = "2c562c1a18d720d4885546083ec8eaad6773a6b80befb02564088cc1e55b304e"
    $nuget = Initialize-ExeFromUrl `
        -filename "nuget.exe" `
        -url $url `
        -expectedSha256Hash $expectedHash
    return $nuget
}

Function Initialize-NugetAssembly([string]$packagename, [string]$packageversion, [string]$assemblypath, [string]$expectedSha256Hash)
{
	$workFolder = "$($env:temp)\$($packagename)_$($packageversion)\"

	$nuget = Initialize-NugetExe
	Push-Location
	try
	{	
		mkdir -Force $workFolder | Out-Null
		Set-Location $workFolder
		&$nuget install $packagename -Version $packageversion -Verbosity Quiet
		$assembly = "$workfolder\$packagename.$packageversion$assemblypath"
		if (Test-Sha256Sum $assembly $expectedSha256Hash)
		{
			[Void][Reflection.Assembly]::LoadFrom($assembly)
		}
		else 
		{
			throw ("Hash mismatch, expected $expectedSha256Hash")
		}
	}
	finally
	{
		Pop-Location
	}

}

function Initialize-IdentityModel()
{
    Initialize-NugetAssembly `
        -packagename "Dlbr.CommonLogin.IdentityModel" `
        -packageversion "0.0.23" `
        -assemblypath "\lib\net45\Dlbr.CommonLogin.IdentityModel.dll" `
        -expectedSha256Hash "f6257bae208438aed6a6743f4b0ce4ed9abbaf40d33d0970e0c533e395bf737f"
}

function Get-Token($idp = $(throw "Specify IdP (e.g. si-idp.vfltest.dk)"),
                           $audience = $(throw "Specify audience"),
                           $username = $(throw "Specify Username"),
                           $password = $(throw "Specify password"))
{
    Write-Host "Requesting token for $username at $audience / $idp"
    $wsTrustClient = New-Object Dlbr.CommonLogin.IdentityModel.WsTrustClient($idp)
    $token = $wsTrustClient.GetSecurityToken($audience, $username, $password)
    Write-Host "Issued token $($token.Id)"
    return $token
}


function Get-DeflatedToken($Token)
{
    $tokenXml = $token.TokenXml.OuterXml
    $deflater = New-Object Dlbr.CommonLogin.IdentityModel.WebApi.DeflatedSamlTokenHeaderEncoder
    $blob = $deflater.Encode($tokenXml)
    return $blob
}

Initialize-IdentityModel 

$token = Get-Token $config.Idp $config.Audience $config.Serviceaccountusername $config.Serviceaccountpassword
$authzHeaderTokenBlob = Get-DeflatedToken $token
$headers = @{}
$headers.Authorization = "Bearer $authzHeaderTokenBlob"
$contenttype = "application/json;charset=utf-8"
$response = Invoke-WebRequest -Method Get -Headers $headers -ContentType $contenttype -UseBasicParsing -Uri $config.Serviceurl
Write-Host "$($response.StatusCode) $response"