Skip to main content

Major update to my Exch-Rest Powershell Module for accessing Office365 and Exchange 2016 Mailboxes via REST

For about a year I've being working on a PowerShell Module for accessing the new REST API for Office365 (the Graph API) and Exchange 2016. I've been experimenting and listening to the various feedback I've been getting and finally have an update to share that addresses a lot of the useability issues (okay it was just too developer orientated).

Application registrations

Still probably the biggest stumbling block is not having an application registration, I now have a menu that allows to you use various default registrations for testing and also to save a default registration that you create. This means once you have your own registration setup you can save the ClientId so it will be used as the default when you next use the module.

Aliasing

A failure in proper planning when I initially created the module meant I didn't use a specific alias for the cmdlets in the module which meant it can cause a lot of conflicts if you have other modules loaded. With the new version all cmldets have a -EXR moniker.

Token Caching

With previous versions of the module you basically would authenticate and create an access token and store that in a local variable which you then had to pass into each of the cmdlets using the -AccessToken parameter along with the MailboxName. This meant a lot of typing and really broke the useability flow without really providing any security benefits. With the new module while all these old behaviours are still valid there is now a Connect-EXRMailbox cmdlet which is the new entry point cmdlet which will store the token and the name of the mailbox associated with the Token in a script variable (encrypted of course) but accessible by the module. This means you can run most of the cmdlets without specifying a Mailbox or Access Token if you just want to return details about the current mailbox that has been authenticated. Also when it comes to using Directory or Reporting cmdlets it eliminates the need for MailboxName which used mandatory parameter on all cmdlets. 

New Getting Started Guide 

With this type of project documentation is the hardest thing as its the least interesting and more time consuming things to get correct. I've written a new getting Started Guide for people that haven't used the module before. The old readme guide is still valid so if your looking to use App Tokens this going to be useful

New Cmdlets

I have a lot of new cmldets most aren't documented in anyway but I hope to put these more into Context in the new year on the blog and on GitHub. Things like accessing the Reporting API's is interesting which I've covered briefly in the new Getting Started guide.

The new module Exch-Rest is available from the PowerShell Gallery here or the source code which will contains all the latest code is available on GitHub here.

 Feedback and Contributions

As always I welcome any feedback or contributors who want to improve the module

Popular posts from this blog

Testing and Sending email via SMTP using Opportunistic TLS and oAuth in Office365 with PowerShell

As well as EWS and Remote PowerShell (RPS) other mail protocols POP3, IMAP and SMTP have had OAuth authentication enabled in Exchange Online (Official announcement here ). A while ago I created  this script that used Opportunistic TLS to perform a Telnet style test against a SMTP server using SMTP AUTH. Now that oAuth authentication has been enabled in office365 I've updated this script to be able to use oAuth instead of SMTP Auth to test against Office365. I've also included a function to actually send a Message. Token Acquisition  To Send a Mail using oAuth you first need to get an Access token from Azure AD there are plenty of ways of doing this in PowerShell. You could use a library like MSAL or ADAL (just google your favoured method) or use a library less approach which I've included with this script . Whatever way you do this you need to make sure that your application registration  https://docs.microsoft.com/en-us/azure/active-directory/develop/quickstart-register-

How to test SMTP using Opportunistic TLS with Powershell and grab the public certificate a SMTP server is using

Most email services these day employ Opportunistic TLS when trying to send Messages which means that wherever possible the Messages will be encrypted rather then the plain text legacy of SMTP.  This method was defined in RFC 3207 "SMTP Service Extension for Secure SMTP over Transport Layer Security" and  there's a quite a good explanation of Opportunistic TLS on Wikipedia  https://en.wikipedia.org/wiki/Opportunistic_TLS .  This is used for both Server to Server (eg MTA to MTA) and Client to server (Eg a Message client like Outlook which acts as a MSA) the later being generally Authenticated. Basically it allows you to have a normal plain text SMTP conversation that is then upgraded to TLS using the STARTTLS verb. Not all servers will support this verb so if its not supported then a message is just sent as Plain text. TLS relies on PKI certificates and the administrative issue s that come around certificate management like expired certificates which is why I wrote th

The MailboxConcurrency limit and using Batching in the Microsoft Graph API

If your getting an error such as Application is over its MailboxConcurrency limit while using the Microsoft Graph API this post may help you understand why. Background   The Mailbox  concurrency limit when your using the Graph API is 4 as per https://docs.microsoft.com/en-us/graph/throttling#outlook-service-limits . This is evaluated for each app ID and mailbox combination so this means you can have different apps running under the same credentials and the poor behavior of one won't cause the other to be throttled. If you compared that to EWS you could have up to 27 concurrent connections but they are shared across all apps on a first come first served basis. Batching Batching in the Graph API is a way of combining multiple requests into a single HTTP request. Batching in the Exchange Mail API's EWS and MAPI has been around for a long time and its common, for email Apps to process large numbers of smaller items for a variety of reasons.  Batching in the Graph is limited to a m
All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.