private bool IsToHanlde(SendGridEvent sendGridEvent)
{
// TODO: trace the messages that should not be handled for debugging purposes.
// For now this service can handle only bounced and dropped events.
return
(sendGridEvent.EventType.EqualsIgnoreCase(SendGridEventTypes.Bounce) || sendGridEvent.EventType.EqualsIgnoreCase(SendGridEventTypes.Dropped)) &&
sendGridEvent.SitefinityCampaignId != Guid.Empty &&
sendGridEvent.SitefinitySubscriberId != Guid.Empty;
}
/// <summary>
/// Handles the notifications events sent by SendGrid.
/// </summary>
/// <param name="events">An array of the events that have occurred.</param>
public void Post(SendGridEvent[] events)
{
if (this.IsToRequireAuthentication())
{
ServiceUtility.RequestBackendUserAuthentication();
}
// TODO: provider name should be configurable
// TODO: get the manager only if an event that we are interested in is present in the events variable.
// Could be done with a property but I am not aware of the this object lifecycle at the moment.
// TODO: Ideally the whole data related operations like getting subscribers, campaigns and writing statistics
// should be in a separate component and not in the service itself.
var newslettersManager = NewslettersManager.GetManager();
var isToSaveChanges = false;
// TODO: Use dynamic objects and inspect them for the required properties instead of
// this strongly typed approach since the different events have very different properties
// and this hook should be able to handle all and not throw exceptions if an event that is
// not supported is received.
foreach (var sendGridEvent in events)
{
// TODO: rewrite this with chain of responsibility so that additional event handlers can be easily added.
if (this.IsToHanlde(sendGridEvent))
{
BounceStatus bounceStatus = this.ResolveStatus(sendGridEvent);
Campaign campaign;
Subscriber subscriber;
try
{
campaign = newslettersManager.GetCampaign(sendGridEvent.SitefinityCampaignId);
subscriber = newslettersManager.GetSubscriber(sendGridEvent.SitefinitySubscriberId);
}
catch (Telerik.Sitefinity.SitefinityExceptions.ItemNotFoundException)
{
// If the campaign or the subscriber is not found we skip to the next event.
break;
}
this.WriteStatistics(newslettersManager, campaign, subscriber, bounceStatus);
this.PerformBounceAction(newslettersManager, subscriber, bounceStatus);
isToSaveChanges = true;
}
}
if (isToSaveChanges)
{
newslettersManager.SaveChanges();
}
this.Response.StatusCode = (int)HttpStatusCode.OK;
}
private BounceStatus ResolveStatus(SendGridEvent sendGridEvent)
{
BounceStatus bounceStatus;
// If the event is for dropped email we mark it as hard bounced.
if (sendGridEvent.EventType.EqualsIgnoreCase(SendGridEventTypes.Dropped))
{
bounceStatus = BounceStatus.Hard;
}
else
{
bounceStatus = MessageParser.GetBounceMessageStatus(sendGridEvent.Status);
}
return bounceStatus;
}