public UsageAggregateByBillingCycle GetUsageAggregateByBillingCycle(Guid orderId, Guid billingCycleId, string resourceId)
{
UsageAggregateByBillingCycle aggregate = null;
string partitionKey = string.Format("{0}-{1}", orderId.ToString(), billingCycleId.ToString());
string rowKey = resourceId;
try
{
aggregate = (from e in this.aggregateTableServiceContext.CreateQuery <UsageAggregateByBillingCycle>(AggregateUsageTableName)
where e.PartitionKey == partitionKey && e.RowKey == rowKey
select e).FirstOrDefault();
}
catch
{
//do nothing, this covers the case when the entity does not exist
//TODO handle other cases
}
return(aggregate);
}
public bool TrackUsage(UsageEvent usage)
{
int statusCode = -1;
BillingCycle currentBillingCyle = this.manager.FetchOrCreateCurrentBillingCycle();
usage.BillingCycleId = currentBillingCyle.Id;
//PartitionKey = orderId + billingCycleId
//RowKey = NewGuid
usage.PartitionKey = string.Format("{0}-{1}", usage.OrderId.ToString(), usage.BillingCycleId.ToString());
usage.RowKey = Guid.NewGuid().ToString();
//locking to reduce contention for aggregate update if multiple events for same order are coming at the same time
//this is not foolproff though. TODO - when updates happen from different servers. check what error Azure
//returns when server1 read, server2 updated, server1 updated
//based on that tweak the business logic
lock (lockObject)
{
//step1 - fetchORcreate and increment aggregate usage
UsageAggregateByBillingCycle aggregate = GetUsageAggregateByBillingCycle(usage.OrderId, usage.BillingCycleId, usage.ResourceId);
bool isNew = false;
if (aggregate == null)
{
aggregate = new UsageAggregateByBillingCycle {
OrderId = usage.OrderId, BillingCycleId = usage.BillingCycleId, ResourceId = usage.ResourceId
};
aggregate.PartitionKey = string.Format("{0}-{1}", usage.OrderId.ToString(), usage.BillingCycleId.ToString());
aggregate.RowKey = usage.ResourceId;
isNew = true;
}
aggregate.AmountConsumed += usage.AmountConsumed;
//step2 - save raw usage
this.tableContext.AddObject(RawUsageTableName, usage);
if (isNew)
{
this.aggregateTableServiceContext.AddObject(AggregateUsageTableName, aggregate);
}
else
{
this.aggregateTableServiceContext.UpdateObject(aggregate);
}
//Now add logic for per user aggregate
UsageAggregatePerUserByBillingCycle aggregatePerUser = GetUsageAggregatePerUserByBillingCycle(usage.OrderId, usage.BillingCycleId, usage.ResourceId, usage.UserId);
isNew = false;
if (aggregatePerUser == null)
{
aggregatePerUser = new UsageAggregatePerUserByBillingCycle {
OrderId = usage.OrderId, BillingCycleId = usage.BillingCycleId, ResourceId = usage.ResourceId,
UserId = usage.UserId
};
aggregatePerUser.PartitionKey = string.Format("{0}-{1}", usage.OrderId.ToString(), usage.BillingCycleId.ToString());
aggregatePerUser.RowKey = string.Format("{0}-{1}", usage.ResourceId, usage.UserId);
isNew = true;
}
aggregatePerUser.AmountConsumed += usage.AmountConsumed;
if (isNew)
{
this.aggregatePerUserTableServiceContext.AddObject(AggregatePerUserUsageTableName, aggregatePerUser);
}
else
{
this.aggregatePerUserTableServiceContext.UpdateObject(aggregatePerUser);
}
//end
DataServiceResponse response = this.tableContext.SaveChangesWithRetries(SaveChangesOptions.Batch);
response = this.aggregateTableServiceContext.SaveChangesWithRetries(SaveChangesOptions.Batch);
statusCode = response.BatchStatusCode;
}
return(statusCode == Http200 || statusCode == 202);
}
