code.grnet.gr Git - pithos-ms-client/blob - trunk/Pithos.Core/Agents/FileEventIdleBatch.cs

   1 #region
   2 /* -----------------------------------------------------------------------
   3  * <copyright file="FileEventIdleBatch.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 using System;
  43 using System.Collections.Generic;
  44 using System.IO;
  45 using System.Linq;
  46 using System.Reflection;
  47 using log4net;
  48
  49 namespace Pithos.Core.Agents
  50 {
  51     public class FileEventIdleBatch
  52     {
  53
  54         //Requirements
  55         //------------
  56         //* The class should group workflow actions according to file name and type
  57         //* The class should pass all batched actions to a continuation when
  58         //* the batch is triggered.
  59         //* Actions should not survice a trigger
  60
  61         private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
  62
  63         private readonly IdleBatch<FileSystemEventArgs> _idleBatch;
  64         private readonly Action<Dictionary<string, FileSystemEventArgs[]>> _callback;
  65
  66         public FileEventIdleBatch(int idleTimeout, Action<Dictionary<string, FileSystemEventArgs[]>> callback)
  67         {
  68             _callback = callback;
  69             _idleBatch = new IdleBatch<FileSystemEventArgs>(idleTimeout, Process);
  70         }
  71
  72         public void Post(FileSystemEventArgs arg)
  73         {
  74             if (Log.IsDebugEnabled)
  75                 Log.DebugFormat("Batch Post  {0}:{1}", arg.ChangeType.ToString("g"), arg.FullPath);
  76
  77             _idleBatch.Post(arg);
  78         }
  79
  80         public void ForceTrigger()
  81         {
  82             _idleBatch.ForceTrigger();
  83         }
  84
  85
  86         protected virtual void Process(FileSystemEventArgs[] args)
  87         {
  88             var dict = new Dictionary<string, FileSystemEventArgs[]>();
  89             foreach (var arg in args)
  90             {
  91
  92                 if (arg.ChangeType == WatcherChangeTypes.Created )
  93                     dict[arg.FullPath] = new[] { arg };
  94                 else if (arg.ChangeType == WatcherChangeTypes.Renamed)
  95                 {
  96                     var renamedArg = (RenamedEventArgs)arg;
  97                     FileSystemEventArgs[] oldValue;
  98                     if (dict.TryGetValue(renamedArg.OldFullPath, out oldValue))
  99                     {
 100                         dict.Remove(renamedArg.OldFullPath);
 101                         var last = oldValue.Last();
 102                         if (last.ChangeType == WatcherChangeTypes.Created)
 103                         {
 104                             var createRenamed = new FileSystemEventArgs(WatcherChangeTypes.Created, Path.GetDirectoryName(renamedArg.FullPath),
 105                                                                         renamedArg.Name);
 106                             dict[renamedArg.FullPath] = new[] {createRenamed};
 107                         }
 108                         else
 109                             dict[renamedArg.FullPath] = new[] { renamedArg };
 110                     }
 111                     else
 112                         dict[renamedArg.FullPath] = new[] { renamedArg};
 113                 }
 114                 else
 115                 {
 116                     FileSystemEventArgs[] oldValue;
 117                     var hasValue=dict.TryGetValue(arg.FullPath, out oldValue);
 118                     var last = hasValue?oldValue.LastOrDefault():null;
 119
 120                     if (last==null || last.ChangeType == WatcherChangeTypes.Changed)
 121                     {
 122                         dict[arg.FullPath] = new[] { arg};
 123                     }
 124                     else if (arg.ChangeType == WatcherChangeTypes.Deleted)
 125                     {
 126                         if (last.ChangeType == WatcherChangeTypes.Created)
 127                             dict.Remove(arg.FullPath);
 128                         else
 129                         {
 130                             dict[arg.FullPath] = new[] { arg };
 131                         }
 132                     }
 133                     else if (last.ChangeType == WatcherChangeTypes.Renamed && arg.ChangeType == WatcherChangeTypes.Changed)
 134                     {
 135                         var newValue = oldValue.Concat(new[] { arg }).ToArray();
 136                         dict[arg.FullPath] = newValue;
 137                     }
 138
 139                 }
 140             }
 141             _callback(dict);
 142         }
 143
 144     }
 145
 146 }