private void listTasksWorker(AsyncOperation asyncOp)
{
Exception e = null;
Task[] tasks = null;
try
{
tasks = _syncClient.ListTasks();
}
catch (Exception ex)
{
e = ex;
}
lock (downloadJobs.SyncRoot)
{
taskListJobs.Remove(asyncOp.UserSuppliedState);
}
ListTaskEventArgs args = new ListTaskEventArgs(tasks, e, false, asyncOp.UserSuppliedState);
asyncOp.PostOperationCompleted(onListTasksCompletedDelegate, args);
}
/// <summary>
/// Starts a loop checking the status of active tasks on server
/// The loop ends when another thread calls Stop()
/// </summary>
public void Start(object sender, System.ComponentModel.DoWorkEventArgs e)
{
Error = null;
try
{
DateTime lastCheckTime = DateTime.UtcNow.AddHours(-1);
while (!shouldStop)
{
bool hasJobs = false;
lock (allTasks)
{
if (allTasks.Count > 0)
{
hasJobs = true;
}
}
// Time to sleep in seconds
int sleepTime = 1;
if (hasJobs)
{
OcrSdkTask[] serverTasks = _restClient.ListTasks(lastCheckTime);
lock (allTasks)
{
foreach (OcrSdkTask task in serverTasks)
{
//Console.WriteLine( String.Format( "{0}: {1}", task.Id, task.Status ) );
if (allTasks.ContainsKey(task.Id))
{
allTasks[task.Id] = task;
}
}
// There is no need to check for statuses of all the tasks on the server - just check
// only those that have changed since last call
// This trick should work even if local time is incorrect
if (allTasks.Count > 0)
{
lastCheckTime = allTasks.Values.First().StatusChangeTime;
}
foreach (OcrSdkTask task in allTasks.Values)
{
if (task.StatusChangeTime > lastCheckTime)
{
lastCheckTime = task.StatusChangeTime;
}
}
}
// Slightly decrease lastCheckTime to avoid losing tasks
lastCheckTime = lastCheckTime.AddSeconds(-2);
// Find out when to perform next check
// TODO
}
// Sleep for 1 second
System.Threading.Thread.Sleep(sleepTime * 1000);
}
}
catch (Exception ex)
{
Error = ex;
}
}