private static string CreateRequestQuery(CalendarSyncRequest inputQueueItem)
{
return($"https://graph.microsoft.com/v1.0/users/{inputQueueItem.UserId}/calendarView?startDateTime={inputQueueItem.Start.ToString("s")}&endDateTime={inputQueueItem.End.ToString("s")}&$select=iCalUId,subject,location,organizer,onlineMeetingUrl,start,end&$filter=type eq \'singleInstance\'");
}
public static async Task Run(
[QueueTrigger(Settings.eventQueueName, Connection = "")] CalendarSyncRequest inputQueueItem,
[Queue(Settings.eventQueueName, Connection = "")] ICollector <CalendarSyncRequest> pagingQueueItems,
[Table(Settings.eventTableName, Connection = "")] ICollector <EventEntity> eventEntities,
ILogger log)
{
log.LogInformation($"C# Queue trigger function processed: {inputQueueItem}");
//If app doesn't have access token yet, fetch it from Azure AD
if (string.IsNullOrEmpty(accessToken))
{
accessToken = await AccessTokenHelper.FetchAccessToken();
}
/*
* Create Http Request
* In usual we use DefaultRequestHeaders to add http request header. Because many Azure Functions instance will use same httpClient, it will make conflict to handle it.
* For resolving this, we create HttpRequestMessage for each request.
* https://stackoverflow.com/questions/23521626/modify-request-headers-per-request-c-sharp-httpclient-pcl
* */
string requestQuery = string.IsNullOrEmpty(inputQueueItem.Url) ? CreateRequestQuery(inputQueueItem) : inputQueueItem.Url;
var request = new HttpRequestMessage()
{
RequestUri = new Uri(requestQuery),
Method = HttpMethod.Get
};
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
HttpResponseMessage response = await graphHttpClient.SendAsync(request);
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
//When token expire after 60 min, we need to get new token
accessToken = await AccessTokenHelper.FetchAccessToken();
//App will re-try with same queue message
pagingQueueItems.Add(inputQueueItem);
}
else if (response.StatusCode == HttpStatusCode.TooManyRequests)
{
System.Threading.Thread.Sleep(sleepInterval);
pagingQueueItems.Add(inputQueueItem);
}
else if (response.IsSuccessStatusCode)
{
var responseData = await response.Content.ReadAsAsync <CalendarViewResponse>();
//Pass @odata.nextlink to storage queue for requesting MS graph with multiple Azure Functions node
if (!string.IsNullOrEmpty(responseData.odatanextLink))
{
pagingQueueItems.Add(new CalendarSyncRequest()
{
UserId = inputQueueItem.UserId,
Url = responseData.odatanextLink,
Start = DateTime.Now.AddDays(-1),
End = DateTime.Now
});
}
foreach (Event eventData in responseData.value)
{
eventEntities.Add(new EventEntity(eventData, inputQueueItem.UserId));
}
}
}
