Calling Microsoft Graph API from inside Azure Functions

Question

I\'m trying to write a simple Azure Function that calls the Microsoft Graph API. But I could not make the access_token work. Here is what I\'ve done:

1. Created a

Answer 1

Azure Functions now supports native authentication for the Microsoft Graph. Docs are at https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-microsoft-graph

There's also a video at https://azure.microsoft.com/en-us/resources/videos/azure-friday-navigating-the-microsoft-graph-with-azure-functions-henderson/

For example, you can create an HttpTrigger function and add the following to function.json.

{
   "type": "token",
   "direction": "in",
   "name": "graphToken",
   "resource": "https://graph.microsoft.com",
   "identity": "userFromRequest"
}

Then, you can query the Graph API on behalf of the user making the request. The access token is passed in as a parameter that you can add as a header to an HttpClient

using System.Net; 
using System.Net.Http; 
using System.Net.Http.Headers; 

public static async Task Run(HttpRequestMessage req, string graphToken, TraceWriter log)
{
    HttpClient client = new HttpClient();
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", graphToken);
    return await client.GetAsync("https://graph.microsoft.com/v1.0/me/");
}

You can also run functions with the ClientCredentials authentication mode, which means it runs as an app instead of in the context of a particular user.