NextMeetingsForGraphSample

Microsoft Graph SDK sample application.

This sample implements the Microsoft Graph .Net SDK, with an ADAL authentication provider in an UWP application

Useful links before get into the code !

• https://github.com/microsoftgraph
• https://www.nuget.org/packages/Microsoft.Graph
• https://github.com/OfficeDev/Microsoft-Graph-UWP-Connect-Library
• https://github.com/azuread

Demo application

this UWP application is provided with 3 main features:

• Authentication through ADAL to your O365 Tenant.
• Get users and photos profiles through Microsoft.Graph.
• Get, set and remove events through Microsoft.Graph.

GraphServiceClient et Authentification

Here is a part of the AuthenticationHelper class, which implements IAuthenticationProvider :

public class AuthenticationHelper : IAuthenticationProvider
{


    public async Task<AuthenticationResult> GetAccessTokenAsync()
    {
        if (authContext == null)
            authContext = new AuthenticationContext(Authority);

        AuthenticationResult authResult = null;

        authResult = await authContext.AcquireTokenSilentAsync(GraphResourceId, ClientId);

        if (authResult.Status != AuthenticationStatus.Success && authResult.Error == "failed_to_acquire_token_silently")
            authResult = await authContext.AcquireTokenAsync(GraphResourceId, ClientId, AppRedirectURI, PromptBehavior.Auto);

        if (authResult.Status != AuthenticationStatus.Success)
        {
            if (authResult.Error != "authentication_canceled")
            {
                MessageDialog dialog = new MessageDialog(string.Format("If the error continues, please contact your administrator.\n\nError: {0}\n\n Error Description:\n\n{1}", authResult.Error, authResult.ErrorDescription), "Sorry, an error occurred while signing you in.");
                await dialog.ShowAsync();
            }
        }


        return authResult;

    }

    public async Task AuthenticateRequestAsync(HttpRequestMessage request)
    {
        var authResult = await GetAccessTokenAsync();

        if (authResult.Status != AuthenticationStatus.Success)
        {
            throw new ServiceException(new Error
            {
                 Code = authResult.Error,
                 Message = authResult.ErrorDescription
            });
        }

        request.Headers.Add("Authorization", "Bearer " + authResult.AccessToken); // + token
    }
}

Note : You should implement a real async mechanism. DON'T use a MessageDialog to manage your errors. Use a CancellationToken instead :)

Microsoft.Graph get and push informations to Office 365

Getting Informations

Getting my profile informations (notice the Request() method involved)

GraphServiceClient graphService = new GraphServiceClient(AuthenticationHelper.Current);
return await graphService.Me.Request().GetAsync();

Getting photos from a particular user (notice the Content property used to get the /$value request) :

  // var photoInfo = await graphService.Users[identifier].Photo.Request().GetAsync(); //users/{1}/photo : Getting info about the photo, not the photo itself
  var photoStream = await graphService.Users[identifier].Photo.Content.Request().GetAsync(); //users/{1}/photo/$value : Getting photo stream

  byte[] photoByte = new byte[photoStream.Length];
  photoStream.Read(photoByte, 0, (int)photoStream.Length);

  var bitmapImage = await ImageHelper.SaveImageToCacheAndGetImage(photoByte, fileName);

  return bitmapImage;

Getting events from your calendar view (notice the QueryOption parameters) :

var start = DateTime.UtcNow.ToString("o");
var end = DateTime.UtcNow.AddMonths(1).ToString("o");

QueryOption optionStart = new QueryOption("startDateTime", start);
QueryOption optionEnd = new QueryOption("endDateTime", end);
var calendarView = await graphService.Me.CalendarView.Request(new[] { optionStart, optionEnd }).GetAsync(); // suffit pas

var hasMorePages = true;
var events = new List<Event>();
while (hasMorePages)
{
    foreach (var ev in calendarView.CurrentPage.ToList())
        events.Add(ev);
    hasMorePages = calendarView.NextPageRequest != null;
    if (hasMorePages)
        calendarView = await calendarView.NextPageRequest.GetAsync();
}
return events;

Delete an event :

GraphServiceClient graphService = new GraphServiceClient(AuthenticationHelper.Current);
try
{
    await graphService.Me.Events[id].Request().DeleteAsync();
}
catch (ServiceException ex)
{
    Debug.WriteLine(ex.Error.Message);
}

Adding or Updating an event :

GraphServiceClient graphService = new GraphServiceClient(AuthenticationHelper.Current);
try
{
    if (!String.IsNullOrEmpty(_event.Id))
        await graphService.Me.Events[_event.Id].Request().UpdateAsync(_event);
    else
        await graphService.Me.Events.Request().AddAsync(_event);
}
catch (ServiceException ex)
{
    Debug.WriteLine(ex.Error.Message);
}

Enjoy !