public WorkItemContext(JobQueueEntryContext <WorkItemData> context, object data, string jobId, ILock workItemLock, Func <int, string, Task> progressCallback) : base(context.QueueEntry, context.QueueEntryLock, context.CancellationToken)
{
Data = data;
JobId = jobId;
WorkItemLock = workItemLock;
_progressCallback = progressCallback;
}
protected abstract Task <JobResult> ProcessQueueEntryAsync(JobQueueEntryContext <T> context);
protected async override Task <JobResult> ProcessQueueEntryAsync(JobQueueEntryContext <WorkItemData> context)
{
var workItemDataType = Type.GetType(context.QueueEntry.Value.Type);
if (workItemDataType == null)
{
return(JobResult.FailedWithMessage("Could not resolve work item data type."));
}
object workItemData;
try {
workItemData = await _queue.Serializer.DeserializeAsync(context.QueueEntry.Value.Data, workItemDataType).AnyContext();
} catch (Exception ex) {
return(JobResult.FromException(ex, "Failed to parse work item data."));
}
var handler = _handlers.GetHandler(workItemDataType);
if (handler == null)
{
return(JobResult.FailedWithMessage($"Handler for type {workItemDataType.Name} not registered."));
}
if (context.QueueEntry.Value.SendProgressReports)
{
await _messageBus.PublishAsync(new WorkItemStatus {
WorkItemId = context.QueueEntry.Value.WorkItemId,
Progress = 0,
Type = context.QueueEntry.Value.Type
}).AnyContext();
}
using (var lockValue = await handler.GetWorkItemLockAsync(workItemData, context.CancellationToken).AnyContext()) {
if (lockValue == null)
{
return(JobResult.SuccessWithMessage("Unable to acquire work item lock."));
}
var progressCallback = new Func <int, string, Task>(async(progress, message) => {
if (handler.AutoRenewLockOnProgress && lockValue != null)
{
await lockValue.RenewAsync().AnyContext();
}
await _messageBus.PublishAsync(new WorkItemStatus {
WorkItemId = context.QueueEntry.Value.WorkItemId,
Progress = progress,
Message = message,
Type = context.QueueEntry.Value.Type
}).AnyContext();
});
try {
_logger.Info("Processing {0} work item queue entry ({1}).", workItemDataType.Name, context.QueueEntry.Id);
await handler.HandleItemAsync(new WorkItemContext(context, workItemData, JobId, lockValue, progressCallback)).AnyContext();
} catch (Exception ex) {
await context.QueueEntry.AbandonAsync().AnyContext();
_logger.Error("Error processing {0} work item queue entry ({1}).", workItemDataType.Name, context.QueueEntry.Id);
return(JobResult.FromException(ex, $"Error in handler {workItemDataType.Name}."));
}
await context.QueueEntry.CompleteAsync().AnyContext();
_logger.Info("Completed {0} work item queue entry ({1}).", workItemDataType.Name, context.QueueEntry.Id);
if (context.QueueEntry.Value.SendProgressReports)
{
await _messageBus.PublishAsync(new WorkItemStatus {
WorkItemId = context.QueueEntry.Value.WorkItemId,
Progress = 100,
Type = context.QueueEntry.Value.Type
}).AnyContext();
}
return(JobResult.Success);
}
}