/// <summary>
/// Get a job off the queue to process if available
/// </summary>
/// <returns>
/// Details of the job to run, or NULL if none present
/// </returns>
public async Task <ScheduledJobDetails> GetJobToProcessAsync()
{
// Get message from queue - timeout of 1 min
CloudQueueMessage message = await azureQueueProvider.DequeueAsync(TimeSpan.FromMinutes(1)).ConfigureAwait(false);
ScheduledJobDetails details = null;
//TODO: Add logic to log these every _n_ times instead of once per polling interval (currently 50ms).
// Log.Verbose("Incoming request to get a job to be processed");
if (message != null)
{
// Get entity from table
details = AzureScheduledJobDetails.FromCloudQueueMessage(message);
TableResult result = await azureTableProvider.RetrieveAsync(
ScheduledJobEntity.GetPartitionKey(details.JobType),
ScheduledJobEntity.GetRowKey(details.JobId)).ConfigureAwait(false);
ScheduledJobEntity entity = (ScheduledJobEntity)result.Result;
if (entity == null)
{
// something bad happened in scheduling
Log.Critical(500, "Deleting Job from queue as entity does not exist , jobId {0} ", details.JobId);
await DeleteJobFromQueueAsync(details).ConfigureAwait(false);
details = null;
}
else
{
int currentVersion = entity.Version;
// if version mismatch, that means job has been updated
// We should delete the current message from the Queue
if (currentVersion != details.Version)
{
await DeleteJobFromQueueAsync(details).ConfigureAwait(false);
details = null;
}
}
}
if (details != null)
{
Log.Info("Job to be processed retrieved \r\n" +
"details : {0}", details);
}
return(details);
}
