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.Diagnostics.Contracts;
  45 using System.IO;
  46 using System.Linq;
  47 using System.Reflection;
  48 using log4net;
  49
  50 namespace Pithos.Core.Agents
  51 {
  52     public class FileEventIdleBatch
  53     {
  54
  55         //Requirements
  56         //------------
  57         //* The class should group workflow actions according to file name and type
  58         //* The class should pass all batched actions to a continuation when
  59         //* the batch is triggered.
  60         //* Actions should not survice a trigger
  61
  62         private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
  63
  64         private readonly IdleBatch<FileSystemEventArgs> _idleBatch;
  65         private readonly Action<Dictionary<string, FileSystemEventArgs[]>> _callback;
  66
  67         private PollAgent _pollAgent;
  68
  69         public FileEventIdleBatch(PollAgent pollAgent, int idleTimeout, Action<Dictionary<string, FileSystemEventArgs[]>> callback)
  70         {
  71             _pollAgent = pollAgent;
  72             _callback = callback;
  73             _idleBatch = new IdleBatch<FileSystemEventArgs>(idleTimeout, Process);
  74         }
  75
  76         public void Post(FileSystemEventArgs arg)
  77         {
  78             if (arg is RenamedEventArgs)
  79                 throw new ArgumentException("arg");
  80             Contract.EndContractBlock();
  81             if (Log.IsDebugEnabled)
  82                 Log.DebugFormat("Batch Post  {0}:{1}", arg.ChangeType.ToString("g"), arg.FullPath);
  83
  84             _pollAgent.Pause =true;
  85
  86             _idleBatch.Post(arg);
  87         }
  88
  89         public void ForceTrigger()
  90         {
  91             _idleBatch.ForceTrigger();
  92         }
  93
  94
  95         protected virtual void Process(FileSystemEventArgs[] args)
  96         {
  97             var dict = new Dictionary<string, FileSystemEventArgs[]>();
  98             foreach (var arg in args)
  99             {
 100
 101                 if (arg.ChangeType == WatcherChangeTypes.Created )
 102                     dict[arg.FullPath] = new[] { arg };
 103                 else if (arg.ChangeType == WatcherChangeTypes.Renamed)
 104                 {
 105                     var renamedArg = (MovedEventArgs)arg;
 106                     FileSystemEventArgs[] oldValue;
 107                     if (dict.TryGetValue(renamedArg.OldFullPath, out oldValue))
 108                     {
 109                         dict.Remove(renamedArg.OldFullPath);
 110                         var last = oldValue.Last();
 111                         if (last.ChangeType == WatcherChangeTypes.Created)
 112                         {
 113                             var createRenamed = new FileSystemEventArgs(WatcherChangeTypes.Created, Path.GetDirectoryName(renamedArg.FullPath),
 114                                                                         renamedArg.Name);
 115                             dict[renamedArg.FullPath] = new[] {createRenamed};
 116                         }
 117                         else
 118                             dict[renamedArg.FullPath] = new[] { renamedArg };
 119                     }
 120                     else
 121                         dict[renamedArg.FullPath] = new[] { renamedArg};
 122                 }
 123                 else
 124                 {
 125                     FileSystemEventArgs[] oldValue;
 126                     var hasValue=dict.TryGetValue(arg.FullPath, out oldValue);
 127                     var last = hasValue?oldValue.LastOrDefault():null;
 128
 129                     if (last==null || last.ChangeType == WatcherChangeTypes.Changed)
 130                     {
 131                         dict[arg.FullPath] = new[] { arg};
 132                     }
 133                     else if (arg.ChangeType == WatcherChangeTypes.Deleted)
 134                     {
 135                         if (last.ChangeType == WatcherChangeTypes.Created)
 136                             dict.Remove(arg.FullPath);
 137                         else
 138                         {
 139                             dict[arg.FullPath] = new[] { arg };
 140                         }
 141                     }
 142                     else if (last.ChangeType == WatcherChangeTypes.Renamed && arg.ChangeType == WatcherChangeTypes.Changed)
 143                     {
 144                         var newValue = oldValue.Concat(new[] { arg }).ToArray();
 145                         dict[arg.FullPath] = newValue;
 146                     }
 147
 148                 }
 149             }
 150             _pollAgent.Pause = false;
 151             _callback(dict);
 152         }
 153
 154     }
 155
 156 }