How to generate an access token using PowerShell

Owned by JM Lopez
Last updated: Dec 06, 2022
1 min read

Gord Russell wrote auth.ps1 (thanks!) to generate an access token using Microsoft PowerShell. It implements the Invoke-RestMethod to send an HTTPS POST request to the VSS RESTful web service, then PowerShell deserializes the JavaScript Object Notation (JSON) content into objects.

 

By calling the script as $TK = .\auth.ps1, $TK is populated with a PS object containing the token.

Step-by-step guide

The following steps explain how auth.ps1 works:

  1. Request username and password:

    $user = Read-Host -Prompt 'User name' $pass = Read-Host -Prompt 'password' -AsSecureString



  2. Convert secureString to plain text:

    $BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($pass) $UnsecurePassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)



  3. Generate request Headers with Authentication: Basic:

    $pair = $user + ":" + $UnsecurePassword # Encode the string to the RFC2045-MIME variant of Base64, except not limited to 76 char/line. $bytes = [System.Text.Encoding]::ASCII.GetBytes($pair) $base64 = [System.Convert]::ToBase64String($bytes) # Create the Auth value as the method, a space, and then the encoded pair Method Base64String $basicAuthValue = "Basic $base64"



  4. Make the POST request to /auth/request-token



  5. After populating $TK, it can be used for any of the API calls by: