Creates an X-Api-Signature for making a REST API Call.

Get-XApiSignature.ps1

function Get-XapiSignature($userAgent, $apiKey, $apiSecret) {
    $dateTime = [DateTime]::UtcNow.ToString("yyyyMMddHHmmss");
    $dataToSign = [String]::Format("{0}{1}{2}{3}", $apikey, $userAgent, $dateTime, $apiSecret);
    $sha1 = [System.Security.Cryptography.SHA1]::Create();
    $signedBytes = $sha1.ComputeHash([System.Text.Encoding]::UTF8.GetBytes($dataToSign));
    $signature = [System.Convert]::ToBase64String($signedBytes);
    $sha1.Dispose()
    [String]::Format("{0}:{1}:{2}", $apikey, $dateTime, $signature);
}

ListDomains.ps1

$apiKey = "wxwgtpxWigsBwSIbofT1"
$apiSecret = "Rxqjp7k4NLi/1l0CopFLgpMf7rPJYkU9wmSOwKjs"
$userAgent = "Powershell"
$server = "https://api.emailsrvr.com"
$url = "/v1/domains"
$address = $server+$url

$signature = Get-XapiSignature $userAgent $apiKey $apiSecret

$header = @{ "User-Agent"=$userAgent; "Accept"="application/json"; "X-Api-Signature"=$signature }

$domains = Invoke-RestMethod -Uri $address -Method Get -Headers $header 

$domains.domains | ft