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Use the Microsoft Graph SDKs to batch requests

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Batching is a way of combining multiple requests into a single HTTP request. The requests are combined in a single JSON payload, which is sent via POST to the \$batch endpoint. Microsoft Graph SDKs have a set of classes to simplify how you create batch payloads and parse batch response payloads.

Important

For current limitations with JSON batching in Microsoft Graph, see Known Issues.

Create a batch request

The Microsoft Graph SDKs provide three classes to work with batch requests and responses.

  • BatchRequestStep - Represents a single request (such as GET /me) within a batch. It enables assigning a unique identifier to the request and specifying dependencies between requests.
  • BatchRequestContent - Simplifies creating the batch request payload. It contains multiple BatchRequestStep objects.
  • BatchResponseContent - Simplifies parsing the response from a batch request. It enables you to get all responses, get a specific response by ID, and get the @odata.nextLink property if present.

Automatic batching for request limits

The Microsoft Graph SDK automatically handles batching requests with respect to the limit of 20 requests per batch. This means that if your code exceeds this limit, the SDK splits the requests into separate batches behind the scenes. This ensures that each batch complies with the limitation. You no longer need to manually implement logic to handle this batching limit, which makes your code cleaner and easier to manage.

Simple batching example

This example shows how to send multiple requests in a batch that are not dependent on each other. The service can run the requests in any order. This example gets the user and gets the user's calendar view for the current day.

// Use the request builder to generate a regular
// request to /me
var userRequest = graphClient.Me.ToGetRequestInformation();

var today = DateTime.Now.Date;

// Use the request builder to generate a regular
// request to /me/calendarview?startDateTime="start"&endDateTime="end"
var eventsRequest = graphClient.Me.CalendarView
    .ToGetRequestInformation(requestConfiguration =>
        {
            requestConfiguration.QueryParameters.StartDateTime =
                today.ToString("yyyy-MM-ddTHH:mm:ssK");
            requestConfiguration.QueryParameters.EndDateTime =
                today.AddDays(1).ToString("yyyy-MM-ddTHH:mm:ssK");
        });

// Build the batch
var batchRequestContent = new BatchRequestContentCollection(graphClient);

// Using AddBatchRequestStepAsync adds each request as a step
// with no specified order of execution
var userRequestId = await batchRequestContent
    .AddBatchRequestStepAsync(userRequest);
var eventsRequestId = await batchRequestContent
    .AddBatchRequestStepAsync(eventsRequest);

var returnedResponse = await graphClient.Batch.PostAsync(batchRequestContent);

// De-serialize response based on known return type
try
{
    var user = await returnedResponse
        .GetResponseByIdAsync<User>(userRequestId);
    Console.WriteLine($"Hello {user.DisplayName}!");
}
catch (Exception ex)
{
    Console.WriteLine($"Get user failed: {ex.Message}");
}

// For collections, must use the *CollectionResponse class to deserialize
// The .Value property will contain the *CollectionPage type that the Graph client
// returns from GetAsync().
try
{
    var events = await returnedResponse
        .GetResponseByIdAsync<EventCollectionResponse>(eventsRequestId);
    Console.WriteLine(
        $"You have {events.Value?.Count} events on your calendar today.");
}
catch (Exception ex)
{
    Console.WriteLine($"Get calendar view failed: {ex.Message}");
}

Batches with dependent requests

This example shows how to send multiple requests in a batch that are dependent on each other. The service runs the request in the order specified by the dependencies. This example adds an event with a start time during the current day to the user's calendar and gets the user's calendar view for the current day. To make sure that the calendar review returned includes the new event created, the request for the calendar view is configured as dependent on the request to add the new event. This ensures that the add event request runs first.

Note

If the add event request fails, the get calendar view request fails with a 424 Failed Dependency error.

var today = DateTime.Now.Date;

var newEvent = new Event
{
    Subject = "File end-of-day report",
    Start = new DateTimeTimeZone
    {
        // 5:00 PM
        DateTime = today.AddHours(17)
            .ToString("yyyy-MM-ddTHH:mm:ss"),
        TimeZone = TimeZoneInfo.Local.StandardName,
    },
    End = new DateTimeTimeZone
    {
        // 5:30 PM
        DateTime = today.AddHours(17).AddMinutes(30)
            .ToString("yyyy-MM-ddTHH:mm:ss"),
        TimeZone = TimeZoneInfo.Local.StandardName,
    },
};

// Use the request builder to generate a regular
// POST request to /me/events
var addEventRequest = graphClient.Me.Events
    .ToPostRequestInformation(newEvent);

// Use the request builder to generate a regular
// request to /me/calendarview?startDateTime="start"&endDateTime="end"
var calendarViewRequest = graphClient.Me.CalendarView.ToGetRequestInformation(
    requestConfiguration =>
    {
        requestConfiguration.QueryParameters.StartDateTime =
            today.ToString("yyyy-MM-ddTHH:mm:ssK");
        requestConfiguration.QueryParameters.EndDateTime =
            today.AddDays(1).ToString("yyyy-MM-ddTHH:mm:ssK");
    });

// Build the batch
var batchRequestContent = new BatchRequestContentCollection(graphClient);

// Force the requests to execute in order, so that the request for
// today's events will include the new event created.

// First request, no dependency
var addEventRequestId = await batchRequestContent
    .AddBatchRequestStepAsync(addEventRequest);

// Second request, depends on addEventRequestId
var eventsRequestId = Guid.NewGuid().ToString();
var eventsRequestMessage = await graphClient.RequestAdapter
    .ConvertToNativeRequestAsync<HttpRequestMessage>(calendarViewRequest);
batchRequestContent.AddBatchRequestStep(new BatchRequestStep(
    eventsRequestId,
    eventsRequestMessage,
    [addEventRequestId]));

var returnedResponse = await graphClient.Batch.PostAsync(batchRequestContent);

// De-serialize response based on known return type
try
{
    var createdEvent = await returnedResponse
        .GetResponseByIdAsync<Event>(addEventRequestId);
    Console.WriteLine($"New event created with ID: {createdEvent.Id}");
}
catch (Exception ex)
{
    Console.WriteLine($"Add event failed: {ex.Message}");
}

// For collections, must use the *CollectionResponse class to deserialize
// The .Value property will contain the *CollectionPage type that the Graph client
// returns from GetAsync().
try
{
    var events = await returnedResponse
        .GetResponseByIdAsync<EventCollectionResponse>(eventsRequestId);
    Console.WriteLine(
        $"You have {events.Value?.Count} events on your calendar today.");
}
catch (Exception ex)
{
    Console.WriteLine($"Get calendar view failed: {ex.Message}");
}