Monday, 4 May 2015

Getting started with the Office 365 Unified API

The Office 365 Unified API was recently launched at Build 2015. It uses Azure AD for authentication and has just one endpoint "" which can be used to query for data from any service across Office 365.

This is a very important thing according to me because in the earlier versions of this API we had to query a discovery service and get the URL of the individual service (SharePoint, Outlook, Azure AD etc.) from which we wanted to get the data.  With the new unified endpoint, it becomes easier for us Developers to just query a single endpoint for data from any of the services across Office 365.

Complete information about the Office 365 Unified API can be found here:

I decided to try my hand at the .NET Client Library of the Office 365 Unified API. Here is the complete code for my console application:

1) The very first thing you will need to do is register your application in Azure AD and get the client id. You can think of this as being somewhat similar to registering an App Principal for a SharePoint App (Add-In as it's now called).

For my test app, I have registered a Native Application (as opposed to a Web Application) mostly because the process for a native application is a bit simpler. For a Web Application, you also need a client secret along with the client id. I decided to keep things simple for my first console app.

2) When you register your app to Azure AD, do not forget to grant the appropriate permissions in the "permissions to other applications" 

3) Make a note of your client Id. You will require this in your code:

4) Create a new Console Application Project in Visual Studio and add the following NuGet packages to it:

Active Directory Authentication Library 2.14.201151115

Office 365 unified API client library (preview) 0.2.6-rc

5) Now you are set up to write code against the Office 365 Unified API.

The very first thing you will need to do is get the access token from Azure AD. Once you have the access token,  all you need to do is create an object of the GraphService class and use it to get data from Office 365 provided you have the right permissions set up in Azure AD.

Here is my sample console application code:

Once you run this code, you will get a prompt to enter your Office 365 credentials:

Once you enter the right credentials, the access token will be fetched and passed on to the GraphService client object which will then use it to get the current user from the GraphService.Me property and display it on the console.

Hope you enjoyed reading this as much as I enjoyed fiddling around with this new API :)

1 comment:

Vinaya Bhat said...

Very nice article for the beginner.

I tried to run the application and I get the below error once after accepting the consent.

Sorry, but we’re having trouble signing you in.
Something went wrong.

Additional technical information:
Correlation ID: 52d034fe-a2f8-4da8-b400-a93d8111d178
Timestamp: 2015-11-24 17:39:47Z
AADSTS90092: Non-retryable error has occurred.

Please let me know if I am missing any configuratiuon.