Microsoft Graph SDK Request Next Link of the Batch Response

Question

I am using Microsoft Graph SDK to create a batch request that contains individual requests to request 20 different users. When I call GetNextLinkAsync() the result is always null. I have tried requesting 1000 different users using batch requests each containing 20 individual requests. This works fine, response is always returned in a single batch response.

1. I couldn't understand why the response is returned in single batch response content rather than giving me the link to fetch the next response?
2. Even though next link is null always, how can I follow it using Graph SDK? It is a string. It's not like next page request.

foreach (var batchRequest in batchRequests)
            {
                try
                {
                    var responses = await PostBatchRequest(batchRequest.Request);
                    foreach (var id in batchRequest.RequestIds)
                    {
                        try
                        {
                            var user = await responses.GetResponseByIdAsync<User>(id);
                            users.Add(user.UserPrincipalName, user.Id);

                        } catch (ServiceException e)
                        {
                            logger.LogInformation(e.StatusCode);
                        }
                    }
                } catch (ServiceException e)
                {
                    logger.LogInformation(e.StatusCode);
                }
            }

I couldn't find proper documentation that tells you how to follow next link using Graph SDK or why it is always null for this type of requests, or are there any special type of requests for which next link is returned?

Answer 1

So a lot of this is framework stuff that's inside my wrapper classes, but the crux of the solution to your issue should be inside here:

var results = await batch.ParseAsync<ContactFolderContactsCollectionResponse, IContactFolderContactsCollectionPage>(response => {
    var page = response.Value;
    if (response?.AdditionalData != null && response.AdditionalData.ContainsKey("@odata.nextLink"))
    {
        page.InitializeNextPageRequest(Application.GraphConnection.Client, (string)response.AdditionalData["@odata.nextLink"]);
    }
    return page;
});

In this snippet I'm parsing out a ContactFolderContactsCollectionResponse from a batch with steps generated from a get request that would normally return a IContactFolderContactsCollectionPage. The ContactFolderContactsCollectionResponse is fetched by the wrapper internals using

GetResponseByIdAsync<ContactFolderContactsCollectionResponse>(id)

So it's pretty analogous to what you're doing except that there is probably some kind of UserResponse type that you should probably be using instead of User.

In my case the ContactFolderContactsCollectionResponse contains the IContactFolderContactsCollectionPage I actionally want in the Vvalue property hence:

var page = response.Value;

Now, IContactFolderContactsCollectionPage normally has a NextPageRequest property, but when you parse it directly from the ContactFolderContactsCollectionResponse, this is not filled out. Luckily, we can find the raw @odata.nextPage link in the ContactFolderContactsCollectionResponse's AdditionalData dictionary, and we can set it using the IContactFolderContactsCollectionPage.InitializeNextPageRequest methhod. Hence the :

if (response?.AdditionalData != null && response.AdditionalData.ContainsKey("@odata.nextLink"))
{
    page.InitializeNextPageRequest(Application.GraphConnection.Client, (string)response.AdditionalData["@odata.nextLink"]);
}

Hopefully that give you enough thread to pull on. Sorry if the rest of the syntax is confusing, as I said, a lot of it is operating in a wrapper framework I'm building and I don't have time to build and test a clean solution.

It's also possible that the whole thing is different anyway on account of you having a batch with a thousand steps as opposed to a batch whose steps return thousands of objects like as in my case.

Either way, happy hunting.