jellyfin-server/MediaBrowser.Common.Implementations/ScheduledTasks/ScheduledTaskWorker.cs
2015-04-13 12:34:36 -04:00

688 lines
22 KiB
C#

using MediaBrowser.Common.Configuration;
using MediaBrowser.Common.Events;
using MediaBrowser.Common.Extensions;
using MediaBrowser.Common.ScheduledTasks;
using MediaBrowser.Model.Events;
using MediaBrowser.Model.Logging;
using MediaBrowser.Model.Serialization;
using MediaBrowser.Model.Tasks;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
namespace MediaBrowser.Common.Implementations.ScheduledTasks
{
/// <summary>
/// Class ScheduledTaskWorker
/// </summary>
public class ScheduledTaskWorker : IScheduledTaskWorker
{
public event EventHandler<GenericEventArgs<double>> TaskProgress;
/// <summary>
/// Gets or sets the scheduled task.
/// </summary>
/// <value>The scheduled task.</value>
public IScheduledTask ScheduledTask { get; private set; }
/// <summary>
/// Gets or sets the json serializer.
/// </summary>
/// <value>The json serializer.</value>
private IJsonSerializer JsonSerializer { get; set; }
/// <summary>
/// Gets or sets the application paths.
/// </summary>
/// <value>The application paths.</value>
private IApplicationPaths ApplicationPaths { get; set; }
/// <summary>
/// Gets the logger.
/// </summary>
/// <value>The logger.</value>
private ILogger Logger { get; set; }
/// <summary>
/// Gets the task manager.
/// </summary>
/// <value>The task manager.</value>
private ITaskManager TaskManager { get; set; }
/// <summary>
/// Initializes a new instance of the <see cref="ScheduledTaskWorker" /> class.
/// </summary>
/// <param name="scheduledTask">The scheduled task.</param>
/// <param name="applicationPaths">The application paths.</param>
/// <param name="taskManager">The task manager.</param>
/// <param name="jsonSerializer">The json serializer.</param>
/// <param name="logger">The logger.</param>
/// <exception cref="System.ArgumentNullException">
/// scheduledTask
/// or
/// applicationPaths
/// or
/// taskManager
/// or
/// jsonSerializer
/// or
/// logger
/// </exception>
public ScheduledTaskWorker(IScheduledTask scheduledTask, IApplicationPaths applicationPaths, ITaskManager taskManager, IJsonSerializer jsonSerializer, ILogger logger)
{
if (scheduledTask == null)
{
throw new ArgumentNullException("scheduledTask");
}
if (applicationPaths == null)
{
throw new ArgumentNullException("applicationPaths");
}
if (taskManager == null)
{
throw new ArgumentNullException("taskManager");
}
if (jsonSerializer == null)
{
throw new ArgumentNullException("jsonSerializer");
}
if (logger == null)
{
throw new ArgumentNullException("logger");
}
ScheduledTask = scheduledTask;
ApplicationPaths = applicationPaths;
TaskManager = taskManager;
JsonSerializer = jsonSerializer;
Logger = logger;
ReloadTriggerEvents(true);
}
/// <summary>
/// The _last execution result
/// </summary>
private TaskResult _lastExecutionResult;
/// <summary>
/// The _last execution result sync lock
/// </summary>
private readonly object _lastExecutionResultSyncLock = new object();
/// <summary>
/// Gets the last execution result.
/// </summary>
/// <value>The last execution result.</value>
public TaskResult LastExecutionResult
{
get
{
if (_lastExecutionResult == null)
{
var path = GetHistoryFilePath();
lock (_lastExecutionResultSyncLock)
{
if (_lastExecutionResult == null)
{
try
{
return JsonSerializer.DeserializeFromFile<TaskResult>(path);
}
catch (DirectoryNotFoundException)
{
// File doesn't exist. No biggie
}
catch (FileNotFoundException)
{
// File doesn't exist. No biggie
}
catch (Exception ex)
{
Logger.ErrorException("Error deserializing {0}", ex, path);
}
}
}
}
return _lastExecutionResult;
}
private set
{
_lastExecutionResult = value;
var path = GetHistoryFilePath();
Directory.CreateDirectory(Path.GetDirectoryName(path));
lock (_lastExecutionResultSyncLock)
{
JsonSerializer.SerializeToFile(value, path);
}
}
}
/// <summary>
/// Gets the name.
/// </summary>
/// <value>The name.</value>
public string Name
{
get { return ScheduledTask.Name; }
}
/// <summary>
/// Gets the description.
/// </summary>
/// <value>The description.</value>
public string Description
{
get { return ScheduledTask.Description; }
}
/// <summary>
/// Gets the category.
/// </summary>
/// <value>The category.</value>
public string Category
{
get { return ScheduledTask.Category; }
}
/// <summary>
/// Gets the current cancellation token
/// </summary>
/// <value>The current cancellation token source.</value>
private CancellationTokenSource CurrentCancellationTokenSource { get; set; }
/// <summary>
/// Gets or sets the current execution start time.
/// </summary>
/// <value>The current execution start time.</value>
private DateTime CurrentExecutionStartTime { get; set; }
/// <summary>
/// Gets the state.
/// </summary>
/// <value>The state.</value>
public TaskState State
{
get
{
if (CurrentCancellationTokenSource != null)
{
return CurrentCancellationTokenSource.IsCancellationRequested
? TaskState.Cancelling
: TaskState.Running;
}
return TaskState.Idle;
}
}
/// <summary>
/// Gets the current progress.
/// </summary>
/// <value>The current progress.</value>
public double? CurrentProgress { get; private set; }
/// <summary>
/// The _triggers
/// </summary>
private IEnumerable<ITaskTrigger> _triggers;
/// <summary>
/// The _triggers sync lock
/// </summary>
private readonly object _triggersSyncLock = new object();
/// <summary>
/// Gets the triggers that define when the task will run
/// </summary>
/// <value>The triggers.</value>
/// <exception cref="System.ArgumentNullException">value</exception>
public IEnumerable<ITaskTrigger> Triggers
{
get
{
if (_triggers == null)
{
lock (_triggersSyncLock)
{
if (_triggers == null)
{
_triggers = LoadTriggers();
}
}
}
return _triggers;
}
set
{
if (value == null)
{
throw new ArgumentNullException("value");
}
// Cleanup current triggers
if (_triggers != null)
{
DisposeTriggers();
}
_triggers = value.ToList();
ReloadTriggerEvents(false);
SaveTriggers(_triggers);
}
}
/// <summary>
/// The _id
/// </summary>
private string _id;
/// <summary>
/// Gets the unique id.
/// </summary>
/// <value>The unique id.</value>
public string Id
{
get
{
if (_id == null)
{
_id = ScheduledTask.GetType().FullName.GetMD5().ToString("N");
}
return _id;
}
}
/// <summary>
/// Reloads the trigger events.
/// </summary>
/// <param name="isApplicationStartup">if set to <c>true</c> [is application startup].</param>
private void ReloadTriggerEvents(bool isApplicationStartup)
{
foreach (var trigger in Triggers)
{
trigger.Stop();
trigger.Triggered -= trigger_Triggered;
trigger.Triggered += trigger_Triggered;
trigger.Start(isApplicationStartup);
}
}
/// <summary>
/// Handles the Triggered event of the trigger control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="EventArgs" /> instance containing the event data.</param>
async void trigger_Triggered(object sender, GenericEventArgs<TaskExecutionOptions> e)
{
var trigger = (ITaskTrigger)sender;
var configurableTask = ScheduledTask as IConfigurableScheduledTask;
if (configurableTask != null && !configurableTask.IsEnabled)
{
return;
}
Logger.Info("{0} fired for task: {1}", trigger.GetType().Name, Name);
trigger.Stop();
TaskManager.QueueScheduledTask(ScheduledTask);
await Task.Delay(1000).ConfigureAwait(false);
trigger.Start(false);
}
private Task _currentTask;
/// <summary>
/// Executes the task
/// </summary>
/// <param name="options">Task options.</param>
/// <returns>Task.</returns>
/// <exception cref="System.InvalidOperationException">Cannot execute a Task that is already running</exception>
public async Task Execute(TaskExecutionOptions options)
{
var task = ExecuteInternal(options);
_currentTask = task;
try
{
await task.ConfigureAwait(false);
}
finally
{
_currentTask = null;
}
}
private async Task ExecuteInternal(TaskExecutionOptions options)
{
// Cancel the current execution, if any
if (CurrentCancellationTokenSource != null)
{
throw new InvalidOperationException("Cannot execute a Task that is already running");
}
var progress = new Progress<double>();
CurrentCancellationTokenSource = new CancellationTokenSource();
Logger.Info("Executing {0}", Name);
((TaskManager)TaskManager).OnTaskExecuting(this);
progress.ProgressChanged += progress_ProgressChanged;
TaskCompletionStatus status;
CurrentExecutionStartTime = DateTime.UtcNow;
Exception failureException = null;
try
{
var localTask = ScheduledTask.Execute(CurrentCancellationTokenSource.Token, progress);
if (options != null && options.MaxRuntimeMs.HasValue)
{
CurrentCancellationTokenSource.CancelAfter(options.MaxRuntimeMs.Value);
}
await localTask.ConfigureAwait(false);
status = TaskCompletionStatus.Completed;
}
catch (OperationCanceledException)
{
status = TaskCompletionStatus.Cancelled;
}
catch (Exception ex)
{
Logger.ErrorException("Error", ex);
failureException = ex;
status = TaskCompletionStatus.Failed;
}
var startTime = CurrentExecutionStartTime;
var endTime = DateTime.UtcNow;
progress.ProgressChanged -= progress_ProgressChanged;
CurrentCancellationTokenSource.Dispose();
CurrentCancellationTokenSource = null;
CurrentProgress = null;
OnTaskCompleted(startTime, endTime, status, failureException);
// Bad practice, i know. But we keep a lot in memory, unfortunately.
GC.Collect(2, GCCollectionMode.Forced, true);
GC.Collect(2, GCCollectionMode.Forced, true);
}
/// <summary>
/// Executes the task.
/// </summary>
/// <param name="cancellationToken">The cancellation token.</param>
/// <param name="progress">The progress.</param>
/// <returns>Task.</returns>
private Task ExecuteTask(CancellationToken cancellationToken, IProgress<double> progress)
{
return Task.Run(async () => await ScheduledTask.Execute(cancellationToken, progress).ConfigureAwait(false), cancellationToken);
}
/// <summary>
/// Progress_s the progress changed.
/// </summary>
/// <param name="sender">The sender.</param>
/// <param name="e">The e.</param>
void progress_ProgressChanged(object sender, double e)
{
CurrentProgress = e;
EventHelper.FireEventIfNotNull(TaskProgress, this, new GenericEventArgs<double>
{
Argument = e
}, Logger);
}
/// <summary>
/// Stops the task if it is currently executing
/// </summary>
/// <exception cref="System.InvalidOperationException">Cannot cancel a Task unless it is in the Running state.</exception>
public void Cancel()
{
if (State != TaskState.Running)
{
throw new InvalidOperationException("Cannot cancel a Task unless it is in the Running state.");
}
CancelIfRunning();
}
/// <summary>
/// Cancels if running.
/// </summary>
public void CancelIfRunning()
{
if (State == TaskState.Running)
{
Logger.Info("Attempting to cancel Scheduled Task {0}", Name);
CurrentCancellationTokenSource.Cancel();
}
}
/// <summary>
/// Gets the scheduled tasks configuration directory.
/// </summary>
/// <returns>System.String.</returns>
private string GetScheduledTasksConfigurationDirectory()
{
return Path.Combine(ApplicationPaths.ConfigurationDirectoryPath, "ScheduledTasks");
}
/// <summary>
/// Gets the scheduled tasks data directory.
/// </summary>
/// <returns>System.String.</returns>
private string GetScheduledTasksDataDirectory()
{
return Path.Combine(ApplicationPaths.DataPath, "ScheduledTasks");
}
/// <summary>
/// Gets the history file path.
/// </summary>
/// <value>The history file path.</value>
private string GetHistoryFilePath()
{
return Path.Combine(GetScheduledTasksDataDirectory(), new Guid(Id) + ".js");
}
/// <summary>
/// Gets the configuration file path.
/// </summary>
/// <returns>System.String.</returns>
private string GetConfigurationFilePath()
{
return Path.Combine(GetScheduledTasksConfigurationDirectory(), new Guid(Id) + ".js");
}
/// <summary>
/// Loads the triggers.
/// </summary>
/// <returns>IEnumerable{BaseTaskTrigger}.</returns>
private IEnumerable<ITaskTrigger> LoadTriggers()
{
try
{
return JsonSerializer.DeserializeFromFile<IEnumerable<TaskTriggerInfo>>(GetConfigurationFilePath())
.Select(ScheduledTaskHelpers.GetTrigger)
.ToList();
}
catch (FileNotFoundException)
{
// File doesn't exist. No biggie. Return defaults.
return ScheduledTask.GetDefaultTriggers();
}
catch (DirectoryNotFoundException)
{
// File doesn't exist. No biggie. Return defaults.
return ScheduledTask.GetDefaultTriggers();
}
}
/// <summary>
/// Saves the triggers.
/// </summary>
/// <param name="triggers">The triggers.</param>
private void SaveTriggers(IEnumerable<ITaskTrigger> triggers)
{
var path = GetConfigurationFilePath();
Directory.CreateDirectory(Path.GetDirectoryName(path));
JsonSerializer.SerializeToFile(triggers.Select(ScheduledTaskHelpers.GetTriggerInfo), path);
}
/// <summary>
/// Called when [task completed].
/// </summary>
/// <param name="startTime">The start time.</param>
/// <param name="endTime">The end time.</param>
/// <param name="status">The status.</param>
private void OnTaskCompleted(DateTime startTime, DateTime endTime, TaskCompletionStatus status, Exception ex)
{
var elapsedTime = endTime - startTime;
Logger.Info("{0} {1} after {2} minute(s) and {3} seconds", Name, status, Math.Truncate(elapsedTime.TotalMinutes), elapsedTime.Seconds);
var result = new TaskResult
{
StartTimeUtc = startTime,
EndTimeUtc = endTime,
Status = status,
Name = Name,
Id = Id
};
var hasKey = ScheduledTask as IHasKey;
if (hasKey != null)
{
result.Key = hasKey.Key;
}
if (ex != null)
{
result.ErrorMessage = ex.Message;
result.LongErrorMessage = ex.StackTrace;
}
LastExecutionResult = result;
((TaskManager)TaskManager).OnTaskCompleted(this, result);
}
/// <summary>
/// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
/// </summary>
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
/// <summary>
/// Releases unmanaged and - optionally - managed resources.
/// </summary>
/// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
protected virtual void Dispose(bool dispose)
{
if (dispose)
{
DisposeTriggers();
var wassRunning = State == TaskState.Running;
var startTime = CurrentExecutionStartTime;
var token = CurrentCancellationTokenSource;
if (token != null)
{
try
{
Logger.Debug(Name + ": Cancelling");
token.Cancel();
}
catch (Exception ex)
{
Logger.ErrorException("Error calling CancellationToken.Cancel();", ex);
}
}
var task = _currentTask;
if (task != null)
{
try
{
Logger.Debug(Name + ": Waiting on Task");
var exited = Task.WaitAll(new[] { task }, 2000);
if (exited)
{
Logger.Debug(Name + ": Task exited");
}
else
{
Logger.Debug(Name + ": Timed out waiting for task to stop");
}
}
catch (Exception ex)
{
Logger.ErrorException("Error calling Task.WaitAll();", ex);
}
}
if (token != null)
{
try
{
Logger.Debug(Name + ": Disposing CancellationToken");
token.Dispose();
}
catch (Exception ex)
{
Logger.ErrorException("Error calling CancellationToken.Dispose();", ex);
}
}
if (wassRunning)
{
OnTaskCompleted(startTime, DateTime.UtcNow, TaskCompletionStatus.Aborted, null);
}
}
}
/// <summary>
/// Disposes each trigger
/// </summary>
private void DisposeTriggers()
{
foreach (var trigger in Triggers)
{
trigger.Triggered -= trigger_Triggered;
trigger.Stop();
}
}
}
}