Monday, December 10, 2018

Updates to the Exch-Rest PowerShell Module to support PowerShell Core, Azure Cloud Shell and more ADAL integration options

I've had some time recently to do some much needed updates to my Exch-Rest module so it now supports both Azure Cloud Shell and PowerShell Core on Linux (tested on RHEL,CentOS, Debian and Ubuntu). So now you can logon to an Office365 Mailbox using this Module with Powershell on Linux and send Email or a Skype for Business Message or do some mailbox reporting eg


The requirements on Linux is you need to be using the latest version of PowerShell core installed as per https://docs.microsoft.com/en-us/powershell/scripting/setup/installing-powershell-core-on-linux?view=powershell-6 .This ensures that all the required .net Core libraries will be available as older version of .Net core didn't have some of the libraries I'm using and I didn't want to backport for older versions.  Also because there are no Linux forms to interact with for authentication you need to pass in the credentials to use via a PSCredential and the code will use the password grant to get the Token eg
$cred = Get-Credential -UserName gscales@datarumble.com
connect-exrmailbox -MailboxName gscales@datarumble.com -Credential $Cred
Azure Cloud Shell

As Cloud Shell is a browser based version of  PowerShell core running on Linux the same connection method of using the credentials as above is needed.

ADAL Integration

I've also added full integration with the ADAL library for authentication so in addition to the native dependency free script methods the module now distributes the ADAL libraries and supports Authentication using that library as well as Token refreshes for scripts that run over an hour etc (using Acquiretokenasync in the ADAL). This supports the following scenarios such as
To use the ADAL libraries for Logon use the following 

connect-exrmailbox -MailboxName gscales@datarumble.com -useADAL

To use the Never Prompt to use the ADAL Cache
connect-exrmailbox -MailboxName gscales@datarumble.com -useADAL -Prompt Never
For connecting using the currently logged on credentials use
connect-exrmailbox -MailboxName gscales@datarumble.com -useADAL -useLoggedOnCredentials -AADUserName gscales@datarumble.com

(The -AADUserName variable is optional but usually required read the GitHub link in the second bullet point)

For those who want to do something simular and are using EWS you will need something like the following to get the AccessToken using ADAL in a normal PowerShell Script.

    $ClientId = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
    $ResourceURI = "https://outlook.office365.com"
    $EndpointUri = 'https://login.microsoftonline.com/common'
    $Context = New-Object Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext($EndpointUri)
    $AADCredential = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.UserCredential" -ArgumentList "username@domain.com"
    $authResult = [Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContextIntegratedAuthExtensions]::AcquireTokenAsync($Context, $ResourceURI, $ClientId, $AADcredential)
    if ($authResult.Result.AccessToken) {
        $token = $authResult.Result
    }
    elseif ($authResult.Exception) {    
        throw "An error occured getting access token: $($authResult.Exception.InnerException)"    
    }
    return $token

This also goes along with support for using the Module in an Azure Runbook which was added last month.

The Exch-REST Module is available from the PowerShell Gallery https://www.powershellgallery.com/packages/Exch-Rest and GitHub https://github.com/gscales/Exch-Rest

A big thankyou to all those people who provided feedback on using the module hopefully these upgrades make it easier to use in more scenarios.

Hire me - If you would like to do something similar to this or anything else you see on my blog I'm currently available to help with any Office365,Microsoft Teams, Exchange or Active Directory related development work or scripting, please contact me at gscales@msgdevelop.com (nothing too big or small).