public async Task<ActionResult> Register(string notificationUrl)
{
try
{
// Get an access token to use when calling the Outlook REST APIs.
var token = await TokenHelper.GetTokenForApplicationAsync(TokenHelper.OutlookResourceID);
var httpClient = new HttpClient();
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
// Create and send a subscription message for newly created calendar events.
var response = await httpClient.PostAsJsonAsync(TokenHelper.OutlookResourceID + "api/v2.0/me/subscriptions",
new PushSubscriptionModel
{
NotificationURL = notificationUrl,
Resource = TokenHelper.OutlookResourceID + "api/v2.0/me/events",
ChangeType = "Created",
ClientState = Guid.NewGuid()
});
if (!response.IsSuccessStatusCode)
{
// Return to error page.
return View("Error");
}
// Deserialize the response.
var responseString = await response.Content.ReadAsStringAsync();
var subscription = JsonConvert.DeserializeObject<PushSubscriptionModel>(responseString);
// Save the subscription ID to map with the current user.
var entities = new ApplicationDbContext();
entities.SubscriptionList.Add(new Subscription
{
SubscriptionId = subscription.Id,
SubscriptionExpirationDateTime = subscription.SubscriptionExpirationDateTime,
SignedInUserID = ClaimsPrincipal.Current.FindFirst(ClaimTypes.NameIdentifier).Value,
TenantID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/tenantid").Value,
UserObjectID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier").Value
});
await entities.SaveChangesAsync();
return View("Success");
}
catch (AdalException)
{
// Return to error page.
return View("Error");
}
// If the above failed, the user needs to explicitly re-authenticate for
// the app to obtain the required token.
catch (Exception)
{
return View("Relogin");
}
}
/// <summary>
/// Responds to requests generated by subscriptions registered with
/// the Outlook Notifications REST API.
/// </summary>
/// <param name="validationToken">The validation token sent by Outlook when
/// validating the Notification URL for the subscription.</param>
public async Task<HttpResponseMessage> Post(string validationToken = null)
{
// If a validation token is present, we need to respond within 5 seconds.
if (validationToken != null)
{
var response = Request.CreateResponse(HttpStatusCode.OK);
response.Content = new StringContent(validationToken);
return response;
}
// Present only if the client specified the ClientState property in the
// subscription request.
IEnumerable<string> clientStateValues;
Request.Headers.TryGetValues("ClientState", out clientStateValues);
if (clientStateValues != null)
{
var clientState = clientStateValues.ToList().FirstOrDefault();
if (clientState != null)
{
// TODO: Use the client state to verify the legitimacy of the notification.
}
}
// Read and parse the request body.
var content = await Request.Content.ReadAsStringAsync();
var notifications = JsonConvert.DeserializeObject<ResponseModel<NotificationModel>>(content).Value;
// TODO: Do something with the notification.
var entities = new ApplicationDbContext();
foreach (var notification in notifications)
{
// Get the subscription from the database in order to locate the
// user identifiers. This is used to tap the token cache.
var subscription = entities.SubscriptionList.FirstOrDefault(s =>
s.SubscriptionId == notification.SubscriptionId);
try
{
// Get an access token to use when calling the Outlook REST APIs.
var token = await TokenHelper.GetTokenForApplicationAsync(
subscription.SignedInUserID,
subscription.TenantID,
subscription.UserObjectID,
TokenHelper.OutlookResourceID);
var httpClient = new HttpClient();
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
// Send a GET call to the monitored event.
var responseString = await httpClient.GetStringAsync(notification.Resource);
var calendarEvent = JsonConvert.DeserializeObject<CalendarEventModel>(responseString);
// TODO: Do something with the calendar event.
}
catch (AdalException)
{
// TODO: Handle token error.
}
// If the above failed, the user needs to explicitly re-authenticate for
// the app to obtain the required token.
catch (Exception)
{
// TODO: Handle exception.
}
}
return new HttpResponseMessage(HttpStatusCode.OK);
}
