public static async Task <IActionResult> RunAsync(
[HttpTrigger(AuthorizationLevel.Function, "post", Route = Constants.Routes.EventConfigs)] HttpRequest req,
ILogger log,
CancellationToken cancellationToken)
{
string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
var entity = JsonConvert.DeserializeObject <PseudoEvent>(requestBody);
if (entity == null)
{
return(new BadRequestResult());
}
var timestamp = entity.EventTimestamp.AddMinutes(-entity.LeadTimeInMinutes);
if (timestamp < DateTimeOffset.UtcNow)
{
return(new NoContentResult());
}
var payload = new EventDispatchTrigger
{
DispatchedAt = DateTimeOffset.UtcNow,
Payload = entity,
PayloadType = nameof(PseudoEvent),
EntityId = entity.Id.ToString(),
EntityTag = DateTimeOffset.UtcNow.ToString("O") // For Cosmos DB entities this could be the ETag value
};
var message = new ServiceBusMessage
{
Subject = nameof(EventDispatchTrigger),
MessageId = entity.Id.ToString(),
Body = BinaryData.FromObjectAsJson(payload),
ContentType = "application/json",
CorrelationId = Guid.NewGuid().ToString()
};
await FunctionHelper.ScheduleTrigger(message, timestamp, log, cancellationToken);
return(new OkResult());
}
public static async Task RunAsync([ServiceBusTrigger(
queueName: "%" + Constants.Configurations.ServiceBusQueueName + "%",
Connection = Constants.Configurations.ServiceBusConnectionString)]
ServiceBusReceivedMessage message,
ILogger log,
CancellationToken cancellationToken)
{
if (message == null || (message.Body?.ToArray()?.Length ?? 0) < 0 || message.Subject != nameof(EventDispatchTrigger))
{
return;
}
log.LogInformation($"Service Bus trigger message received (id={message.MessageId}, enqueued={message.EnqueuedTime})");
var trigger = message.Body.ToObjectFromJson <EventDispatchTrigger>();
// Note: At this place you would load the entity referenced by trigger information from data storage
var entity = JsonConvert.DeserializeObject <PseudoEvent>(JsonConvert.SerializeObject(trigger.Payload));
var entityTag = trigger.EntityTag; // For Cosmos DB entities this could be the ETag value
// Check if entity version is still current: If not, another message has been scheduled already
if (entityTag != trigger.EntityTag)
{
log.LogInformation($"Non-current trigger message detected and ignored (id={message.MessageId}, enqueued={message.EnqueuedTime})");
return;
}
// Dispatch event
// Something like: Dispatch an event to EventGrid
// Schedule recurring event
if (entity.RecurrenceIntervall != RecurrenceIntervall.None)
{
var nextTimestamp = entity.EventTimestamp.AddMinutes(-entity.LeadTimeInMinutes);
var diff = DateTimeOffset.UtcNow - nextTimestamp;
switch (entity.RecurrenceIntervall)
{
case RecurrenceIntervall.Daily:
{
nextTimestamp.AddDays(Math.Ceiling(diff.TotalDays));
break;
}
case RecurrenceIntervall.Weekly:
{
nextTimestamp.AddDays(Math.Ceiling(diff.TotalDays / 7) * 7);
break;
}
case RecurrenceIntervall.Monthly:
{
nextTimestamp.AddMonths((int)Math.Ceiling(diff.TotalDays / 30));
break;
}
case RecurrenceIntervall.Yearly:
{
nextTimestamp.AddYears((int)Math.Ceiling(diff.TotalDays / 365));
break;
}
default:
{
log.LogError($"Type '{entity.RecurrenceIntervall}' of recurrence not supported");
return;
}
}
var payload = new EventDispatchTrigger
{
DispatchedAt = DateTimeOffset.UtcNow,
Payload = entity,
PayloadType = nameof(PseudoEvent),
EntityId = trigger.EntityId,
EntityTag = trigger.EntityTag
};
var nextMessage = new ServiceBusMessage
{
Subject = nameof(EventDispatchTrigger),
MessageId = trigger.EntityId,
Body = BinaryData.FromObjectAsJson(payload),
ContentType = "application/json",
CorrelationId = message.CorrelationId
};
await FunctionHelper.ScheduleTrigger(nextMessage, nextTimestamp, log, cancellationToken);
}
}
