code.grnet.gr Git - pithos-ms-client/blob - trunk%2FPithos.Core%2FAgents%2FNetworkAgent.cs

   1 #region
   2 /* -----------------------------------------------------------------------
   3  * <copyright file="NetworkAgent.cs" company="GRNet">
   4  *
   5  * Copyright 2011-2012 GRNET S.A. All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or
   8  * without modification, are permitted provided that the following
   9  * conditions are met:
  10  *
  11  *   1. Redistributions of source code must retain the above
  12  *      copyright notice, this list of conditions and the following
  13  *      disclaimer.
  14  *
  15  *   2. Redistributions in binary form must reproduce the above
  16  *      copyright notice, this list of conditions and the following
  17  *      disclaimer in the documentation and/or other materials
  18  *      provided with the distribution.
  19  *
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
  22  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  24  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
  25  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  28  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  31  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  * The views and conclusions contained in the software and
  35  * documentation are those of the authors and should not be
  36  * interpreted as representing official policies, either expressed
  37  * or implied, of GRNET S.A.
  38  * </copyright>
  39  * -----------------------------------------------------------------------
  40  */
  41 #endregion
  42
  43 using System;
  44 using System.Collections.Generic;
  45 using System.ComponentModel.Composition;
  46 using System.Diagnostics;
  47 using System.Diagnostics.Contracts;
  48 using System.IO;
  49 using System.Net;
  50 using System.Reflection;
  51 using System.Threading;
  52 using System.Threading.Tasks;
  53 using Castle.ActiveRecord;
  54 using Pithos.Interfaces;
  55 using Pithos.Network;
  56 using log4net;
  57
  58 namespace Pithos.Core.Agents
  59 {
  60     [Export]
  61     public class NetworkAgent
  62     {
  63         private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
  64
  65         private Agent<CloudAction> _agent;
  66
  67         [System.ComponentModel.Composition.Import]
  68         private DeleteAgent DeleteAgent { get; set; }
  69
  70         [System.ComponentModel.Composition.Import]
  71         public IStatusKeeper StatusKeeper { get; set; }
  72
  73         private IStatusNotification _statusNotification;
  74         public IStatusNotification StatusNotification
  75         {
  76             get { return _statusNotification; }
  77             set
  78             {
  79                 _statusNotification = value;
  80                 DeleteAgent.StatusNotification = value;
  81                 Uploader.StatusNotification = value;
  82                 Downloader.StatusNotification = value;
  83             }
  84         }
  85
  86
  87         [System.ComponentModel.Composition.Import]
  88         public IPithosSettings Settings { get; set; }
  89
  90         [System.ComponentModel.Composition.Import]
  91         public Uploader Uploader { get; set; }
  92
  93         [System.ComponentModel.Composition.Import]
  94         public Downloader Downloader { get; set; }
  95
  96         //The Proceed signals the poll agent that it can proceed with polling.
  97         //Essentially it stops the poll agent to give priority to the network agent
  98         //Initially the event is signalled because we don't need to pause
  99         private readonly AsyncManualResetEvent _proceedEvent = new AsyncManualResetEvent(true);
 100
 101         public AsyncManualResetEvent ProceedEvent
 102         {
 103             get { return _proceedEvent; }
 104         }
 105
 106
 107         public void Start()
 108         {
 109             if (_agent != null)
 110                 return;
 111
 112             if (Log.IsDebugEnabled)
 113                 Log.Debug("Starting Network Agent");
 114
 115             _agent = Agent<CloudAction>.Start(inbox =>
 116             {
 117                 Action loop = null;
 118                 loop = () =>
 119                 {
 120                     DeleteAgent.ProceedEvent.Wait();
 121                     var message = inbox.Receive();
 122                     var process=message.Then(Process,inbox.CancellationToken);
 123                     inbox.LoopAsync(process, loop);
 124                 };
 125                 loop();
 126             });
 127
 128         }
 129
 130         private async Task Process(CloudAction action)
 131         {
 132             if (action == null)
 133                 throw new ArgumentNullException("action");
 134             if (action.AccountInfo==null)
 135                 throw new ArgumentException("The action.AccountInfo is empty","action");
 136             Contract.EndContractBlock();
 137
 138
 139
 140
 141             using (ThreadContext.Stacks["Operation"].Push(action.ToString()))
 142             {
 143
 144                 var cloudFile = action.CloudFile;
 145                 var downloadPath = action.GetDownloadPath();
 146
 147                 try
 148                 {
 149                     StatusNotification.SetPithosStatus(PithosStatus.LocalSyncing,"Processing");
 150                     _proceedEvent.Reset();
 151
 152                     var accountInfo = action.AccountInfo;
 153
 154                     if (action.Action == CloudActionType.DeleteCloud)
 155                     {
 156                         //Redirect deletes to the delete agent
 157                         DeleteAgent.Post((CloudDeleteAction)action);
 158                     }
 159                     if (DeleteAgent.IsDeletedFile(action))
 160                     {
 161                         //Clear the status of already deleted files to avoid reprocessing
 162                         if (action.LocalFile != null)
 163                             StatusKeeper.ClearFileStatus(action.LocalFile.FullName);
 164                     }
 165                     else
 166                     {
 167                         switch (action.Action)
 168                         {
 169                             case CloudActionType.UploadUnconditional:
 170                                 //Abort if the file was deleted before we reached this point
 171                                 await Uploader.UploadCloudFile(action);
 172                                 break;
 173                             case CloudActionType.DownloadUnconditional:
 174                                 await Downloader.DownloadCloudFile(accountInfo, cloudFile, downloadPath);
 175                                 break;
 176                             case CloudActionType.RenameCloud:
 177                                 var moveAction = (CloudMoveAction)action;
 178                                 RenameCloudFile(accountInfo, moveAction);
 179                                 break;
 180                             case CloudActionType.RenameLocal:
 181                                 RenameLocalFile(accountInfo, action);
 182                                 break;
 183                             case CloudActionType.MustSynch:
 184                                 if (!File.Exists(downloadPath) && !Directory.Exists(downloadPath))
 185                                 {
 186                                     await Downloader.DownloadCloudFile(accountInfo, cloudFile, downloadPath);
 187                                 }
 188                                 else
 189                                 {
 190                                     await SyncFiles(accountInfo, action);
 191                                 }
 192                                 break;
 193                         }
 194                     }
 195                     Log.InfoFormat("End Processing {0}:{1}->{2}", action.Action, action.LocalFile,
 196                                            action.CloudFile.Name);
 197                 }
 198 /*
 199                 catch (WebException exc)
 200                 {
 201                     Log.ErrorFormat("[WEB ERROR] {0} : {1} -> {2} due to exception\r\n{3}", action.Action, action.LocalFile, action.CloudFile, exc);
 202
 203
 204                     //Actions that resulted in server errors should be retried
 205                     var response = exc.Response as HttpWebResponse;
 206                     if (response != null && response.StatusCode >= HttpStatusCode.InternalServerError)
 207                     {
 208                         _agent.Post(action);
 209                         Log.WarnFormat("[REQUEUE] {0} : {1} -> {2}", action.Action, action.LocalFile, action.CloudFile);
 210                     }
 211                 }
 212 */
 213                 catch (OperationCanceledException)
 214                 {
 215                     throw;
 216                 }
 217                 catch (DirectoryNotFoundException)
 218                 {
 219                     Log.ErrorFormat("{0} : {1} -> {2}  failed because the directory was not found.\n Rescheduling a delete",
 220                         action.Action, action.LocalFile, action.CloudFile);
 221                     //Post a delete action for the missing file
 222                     Post(new CloudDeleteAction(action));
 223                 }
 224                 catch (FileNotFoundException)
 225                 {
 226                     Log.ErrorFormat("{0} : {1} -> {2}  failed because the file was not found.\n Rescheduling a delete",
 227                         action.Action, action.LocalFile, action.CloudFile);
 228                     //Post a delete action for the missing file
 229                     Post(new CloudDeleteAction(action));
 230                 }
 231                 catch (Exception exc)
 232                 {
 233                     Log.ErrorFormat("[REQUEUE] {0} : {1} -> {2} due to exception\r\n{3}",
 234                                      action.Action, action.LocalFile, action.CloudFile, exc);
 235
 236                     _agent.Post(action);
 237                 }
 238                 finally
 239                 {
 240                     if (_agent.IsEmpty)
 241                         _proceedEvent.Set();
 242                     UpdateStatus(PithosStatus.LocalComplete);
 243                 }
 244             }
 245         }
 246
 247
 248         private void UpdateStatus(PithosStatus status)
 249         {
 250             StatusNotification.SetPithosStatus(status);
 251             //StatusNotification.Notify(new Notification());
 252         }
 253
 254         private void RenameLocalFile(AccountInfo accountInfo, CloudAction action)
 255         {
 256             if (accountInfo == null)
 257                 throw new ArgumentNullException("accountInfo");
 258             if (action == null)
 259                 throw new ArgumentNullException("action");
 260             if (action.LocalFile == null)
 261                 throw new ArgumentException("The action's local file is not specified", "action");
 262             if (!Path.IsPathRooted(action.LocalFile.FullName))
 263                 throw new ArgumentException("The action's local file path must be absolute", "action");
 264             if (action.CloudFile == null)
 265                 throw new ArgumentException("The action's cloud file is not specified", "action");
 266             Contract.EndContractBlock();
 267             using (ThreadContext.Stacks["Operation"].Push("RenameLocalFile"))
 268             {
 269
 270                 //We assume that the local file already exists, otherwise the poll agent
 271                 //would have issued a download request
 272
 273                 var currentInfo = action.CloudFile;
 274                 var previousInfo = action.CloudFile.Previous;
 275                 var fileAgent = FileAgent.GetFileAgent(accountInfo);
 276
 277                 var previousRelativepath = previousInfo.RelativeUrlToFilePath(accountInfo.UserName);
 278                 var previousFile = fileAgent.GetFileSystemInfo(previousRelativepath);
 279
 280                 //In every case we need to move the local file first
 281                 MoveLocalFile(accountInfo, previousFile, fileAgent, currentInfo);
 282             }
 283         }
 284
 285         private void MoveLocalFile(AccountInfo accountInfo, FileSystemInfo previousFile, FileAgent fileAgent,
 286                                    ObjectInfo currentInfo)
 287         {
 288             var currentRelativepath = currentInfo.RelativeUrlToFilePath(accountInfo.UserName);
 289             var newPath = Path.Combine(fileAgent.RootPath, currentRelativepath);
 290
 291             var isFile= (previousFile is FileInfo);
 292             var previousFullPath = isFile?
 293                 FileInfoExtensions.GetProperFilePathCapitalization(previousFile.FullName):
 294                 FileInfoExtensions.GetProperDirectoryCapitalization(previousFile.FullName);
 295
 296             using (NetworkGate.Acquire(previousFullPath, NetworkOperation.Renaming))
 297             using (NetworkGate.Acquire(newPath,NetworkOperation.Renaming))
 298             using (new SessionScope(FlushAction.Auto))
 299             {
 300                 if (isFile)
 301                     (previousFile as FileInfo).MoveTo(newPath);
 302                 else
 303                 {
 304                     (previousFile as DirectoryInfo).MoveTo(newPath);
 305                 }
 306                 var state = StatusKeeper.GetStateByFilePath(previousFullPath);
 307                 state.FilePath = newPath;
 308                 state.SaveCopy();
 309                 StatusKeeper.SetFileState(previousFullPath,FileStatus.Deleted,FileOverlayStatus.Deleted);
 310             }
 311         }
 312
 313         private async Task SyncFiles(AccountInfo accountInfo,CloudAction action)
 314         {
 315             if (accountInfo == null)
 316                 throw new ArgumentNullException("accountInfo");
 317             if (action==null)
 318                 throw new ArgumentNullException("action");
 319             if (action.LocalFile==null)
 320                 throw new ArgumentException("The action's local file is not specified","action");
 321             if (!Path.IsPathRooted(action.LocalFile.FullName))
 322                 throw new ArgumentException("The action's local file path must be absolute","action");
 323             if (action.CloudFile== null)
 324                 throw new ArgumentException("The action's cloud file is not specified", "action");
 325             Contract.EndContractBlock();
 326             using (ThreadContext.Stacks["Operation"].Push("SyncFiles"))
 327             {
 328
 329                 //var localFile = action.LocalFile;
 330                 var cloudFile = action.CloudFile;
 331                 var downloadPath = action.LocalFile.GetProperCapitalization();
 332
 333                 var cloudHash = cloudFile.Hash.ToLower();
 334                 var previousCloudHash = cloudFile.PreviousHash.ToLower();
 335                 var localHash = action.TreeHash.Value.TopHash.ToHashString();// LocalHash.Value.ToLower();
 336                 //var topHash = action.TopHash.Value.ToLower();
 337
 338                 //At this point we know that an object has changed on the server and that a local
 339                 //file already exists. We need to decide whether the file has only changed on
 340                 //the server or there is a conflicting change on the client.
 341                 //
 342
 343                 //If the hashes match, we are done
 344                 if (cloudFile != ObjectInfo.Empty && cloudHash == localHash)
 345                 {
 346                     Log.InfoFormat("Skipping {0}, hashes match", downloadPath);
 347                     return;
 348                 }
 349
 350                 //The hashes DON'T match. We need to sync
 351
 352                 // If the previous tophash matches the local tophash, the file was only changed on the server.
 353                 if (localHash == previousCloudHash)
 354                 {
 355                     await Downloader.DownloadCloudFile(accountInfo, cloudFile, downloadPath);
 356                 }
 357                 else
 358                 {
 359                     //If the previous and local hash don't match, there was a local conflict
 360                     //that was not uploaded to the server. We have a conflict
 361                     ReportConflict(downloadPath);
 362                 }
 363             }
 364         }
 365
 366         private void ReportConflict(string downloadPath)
 367         {
 368             if (String.IsNullOrWhiteSpace(downloadPath))
 369                 throw new ArgumentNullException("downloadPath");
 370             Contract.EndContractBlock();
 371
 372             StatusKeeper.SetFileOverlayStatus(downloadPath, FileOverlayStatus.Conflict);
 373             UpdateStatus(PithosStatus.HasConflicts);
 374             var message = String.Format("Conflict detected for file {0}", downloadPath);
 375             Log.Warn(message);
 376             StatusNotification.NotifyChange(message, TraceLevel.Warning);
 377         }
 378
 379         public void Post(CloudAction cloudAction)
 380         {
 381             if (cloudAction == null)
 382                 throw new ArgumentNullException("cloudAction");
 383             if (cloudAction.AccountInfo==null)
 384                 throw new ArgumentException("The CloudAction.AccountInfo is empty","cloudAction");
 385             Contract.EndContractBlock();
 386
 387             DeleteAgent.ProceedEvent.Wait();
 388 /*
 389
 390             //If the action targets a local file, add a treehash calculation
 391             if (!(cloudAction is CloudDeleteAction) && cloudAction.LocalFile as FileInfo != null)
 392             {
 393                 var accountInfo = cloudAction.AccountInfo;
 394                 var localFile = (FileInfo) cloudAction.LocalFile;
 395
 396                 if (localFile.Length > accountInfo.BlockSize)
 397                     cloudAction.TopHash =
 398                         new Lazy<string>(() => Signature.CalculateTreeHashAsync(localFile,
 399                                                                                 accountInfo.BlockSize,
 400                                                                                 accountInfo.BlockHash, Settings.HashingParallelism).Result
 401                                                     .TopHash.ToHashString());
 402                 else
 403                 {
 404                     cloudAction.TopHash = new Lazy<string>(() => cloudAction.LocalHash.Value);
 405                 }
 406
 407             }
 408             else
 409             {
 410                 //The hash for a directory is the empty string
 411                 cloudAction.TopHash = new Lazy<string>(() => String.Empty);
 412             }
 413 */
 414
 415             if (cloudAction is CloudDeleteAction)
 416                 DeleteAgent.Post((CloudDeleteAction)cloudAction);
 417             else
 418                 _agent.Post(cloudAction);
 419         }
 420
 421
 422         public IEnumerable<CloudAction> GetEnumerable()
 423         {
 424             return _agent.GetEnumerable();
 425         }
 426
 427         public Task GetDeleteAwaiter()
 428         {
 429             return DeleteAgent.ProceedEvent.WaitAsync();
 430         }
 431         public CancellationToken CancellationToken
 432         {
 433             get { return _agent.CancellationToken; }
 434         }
 435
 436
 437
 438         private void RenameCloudFile(AccountInfo accountInfo,CloudMoveAction action)
 439         {
 440             if (accountInfo==null)
 441                 throw new ArgumentNullException("accountInfo");
 442             if (action==null)
 443                 throw new ArgumentNullException("action");
 444             if (action.CloudFile==null)
 445                 throw new ArgumentException("CloudFile","action");
 446             if (action.LocalFile==null)
 447                 throw new ArgumentException("LocalFile","action");
 448             if (action.OldLocalFile==null)
 449                 throw new ArgumentException("OldLocalFile","action");
 450             if (action.OldCloudFile==null)
 451                 throw new ArgumentException("OldCloudFile","action");
 452             Contract.EndContractBlock();
 453
 454             using (ThreadContext.Stacks["Operation"].Push("RenameCloudFile"))
 455             {
 456
 457                 var newFilePath = action.LocalFile.FullName;
 458
 459                 //How do we handle concurrent renames and deletes/uploads/downloads?
 460                 //* A conflicting upload means that a file was renamed before it had a chance to finish uploading
 461                 //  This should never happen as the network agent executes only one action at a time
 462                 //* A conflicting download means that the file was modified on the cloud. While we can go on and complete
 463                 //  the rename, there may be a problem if the file is downloaded in blocks, as subsequent block requests for the
 464                 //  same name will fail.
 465                 //  This should never happen as the network agent executes only one action at a time.
 466                 //* A conflicting delete can happen if the rename was followed by a delete action that didn't have the chance
 467                 //  to remove the rename from the queue.
 468                 //  We can probably ignore this case. It will result in an error which should be ignored
 469
 470
 471                 //The local file is already renamed
 472                 StatusKeeper.SetFileOverlayStatus(newFilePath, FileOverlayStatus.Modified);
 473
 474
 475                 var account = action.CloudFile.Account ?? accountInfo.UserName;
 476                 var container = action.CloudFile.Container;
 477
 478                 var client = new CloudFilesClient(accountInfo);
 479                 //TODO: What code is returned when the source file doesn't exist?
 480                 client.MoveObject(account, container, action.OldCloudFile.Name, container, action.CloudFile.Name);
 481
 482                 StatusKeeper.SetFileStatus(newFilePath, FileStatus.Unchanged);
 483                 StatusKeeper.SetFileOverlayStatus(newFilePath, FileOverlayStatus.Normal);
 484                 NativeMethods.RaiseChangeNotification(newFilePath);
 485             }
 486         }
 487
 488
 489
 490     }
 491
 492
 493
 494
 495 }