/// <summary>
/// Creates a new task schedule instance.
/// </summary>
/// <param name="task">The task.</param>
/// <param name="type">The schedule type.</param>
/// <param name="startTime">The start time.</param>
public CrawlerSchedule(CrawlerTask task, ScheduleType type, DateTime startTime)
{
// The identifier.
this.Id = Guid.NewGuid();
// The task.
this.task = task;
// The schedule type.
this.type = type;
// The start time.
this.startTime = startTime;
this.useUniversalStartTime = false;
// Task enabled.
this.enabled = true;
// Settings.
this.delayEnabled = false;
this.delayMaximumInterval = TimeSpan.FromHours(1.0);
this.repeatEnabled = false;
this.repeatInterval = TimeSpan.FromHours(1.0);
this.repeatDuration = TimeSpan.FromDays(1.0);
this.stopAfterRepeatEnabled = false;
this.stopEnabled = false;
this.stopInterval = TimeSpan.FromDays(3.0);
this.expiresEnabled = false;
this.expiresTime = startTime.AddYears(1);
// Create the triggers.
}
/// <summary>
/// Adds a task to the tasks list.
/// </summary>
/// <param name="task"></param>
public void AddTask(CrawlerTask task)
{
// Validate the argument.
if (null == task) throw new ArgumentNullException("task");
// Check the task is in the stopped state.
if (task.State != CrawlerTask.TaskState.Stopped) throw new CrawlerException("Cannot add the task because the it is not in the stopped state.");
// Synchronize access.
lock (this.sync)
{
// Check the task does not exist.
if (this.tasks.ContainsKey(task.Id)) throw new CrawlerException("Cannot add task because a task with the identifier {0} already exists.".FormatWith(task.Id));
// Add the task to the tasks list.
this.tasks.Add(task.Id, task);
// Add the task event handlers.
task.ScheduleAdded += this.OnTaskScheduleAdded;
task.ScheduleRemoved += this.OnTaskScheduleRemoved;
}
// Raise the event.
if (null != this.TaskAdded) this.TaskAdded(this, new CrawlerTaskEventArgs(task));
}
/// <summary>
/// Creates a new event arguments instance.
/// </summary>
/// <param name="task">The crawler task.</param>
public CrawlerTaskEventArgs(CrawlerTask task)
{
this.Task = task;
}
/// <summary>
/// Removes the task from the tasks list asynchronously.
/// </summary>
/// <param name="task">The task.</param>
/// <param name="callback">A method called when the removal has completed.</param>
public void RemoveTask(CrawlerTask task, CrawlerTaskCallback callback)
{
// Validate the arguments.
if (null != task) throw new ArgumentNullException("task");
if (null != callback) throw new ArgumentNullException("callback");
// Call the remove task handler on the thread pool.
ThreadPool.QueueUserWorkItem((object state) =>
{
try
{
// Call the remove the task handler.
this.RemoveTask(task);
}
catch { } // Catch all exceptions
finally
{
// Execute the callback method.
callback(task);
}
});
}
/// <summary>
/// Removes a task from the tasks list.
/// </summary>
/// <param name="task">The task.</param>
public void RemoveTask(CrawlerTask task)
{
// Validate the argument.
if (null == task) throw new ArgumentNullException("task");
// Cancel the task execution.
}