jj: filewatcher

Filesystem/FileWatcher.vb

@@ -1,25 +1,33 @@
 Imports System.IO
+Imports DigitalData.Modules.Filesystem
+Imports DigitalData.Modules.Filesystem.FileWatcherFilters
 Imports DigitalData.Modules.Logging
 
+
 Public Class FileWatcher
+    ' Internals
     Private ReadOnly _Logger As Logger
     Private ReadOnly _Watchers As List(Of FileSystemWatcher)
-    Private ReadOnly _Files As Dictionary(Of String, FileProperties)
+    Private ReadOnly _Files As Dictionary(Of String, FileWatcherProperties)
+    Private ReadOnly _Filters As List(Of BaseFileFilter)
 
+    ' Options
     Private _Path As String
 
-    Public OfficeFilters As New List(Of String) From {"docx", "xlsx", "pptx"}
+    ' Public Events
+    Public Event FileSaved(ByVal FullName As String, ByVal IsSpecial As Boolean)
 
-    Public Sub New(LogConfig As LogConfig, Path As String)
+    Public Sub New(LogConfig As LogConfig, Path As String, Optional Filters As List(Of BaseFileFilter) = Nothing)
         _Logger = LogConfig.GetLogger()
-        _Files = New Dictionary(Of String, FileProperties)
+        _Files = New Dictionary(Of String, FileWatcherProperties)
         _Watchers = New List(Of FileSystemWatcher)
+        _Filters = IIf(IsNothing(Filters), GetDefaultFilters(), Filters)
         _Path = Path
 
-        For Each oFilePath As String In Directory.EnumerateFiles(_Path)
+        For Each oFilePath In Directory.EnumerateFiles(_Path)
             Try
                 If IO.File.Exists(oFilePath) Then
-                    _Files.Add(oFilePath, New FileProperties With {
+                    _Files.Add(oFilePath, New FileWatcherProperties With {
                         .CreatedAt = DateTime.Now,
                         .ChangedAt = Nothing
                     })
@@ -31,58 +39,10 @@ Public Class FileWatcher
         Next
     End Sub
 
-    Public Sub Add(Filter As String, Optional SpecialTreatmentFilters As List(Of String) = Nothing)
+    Public Sub Add(Filter As String)
         _Watchers.Add(CreateWatcher(Filter))
     End Sub
 
-    Public Sub Add(Filters As List(Of String), Optional SpecialTreatmentFilters As List(Of String) = Nothing)
-        For Each oFilter In Filters
-            _Watchers.Add(CreateWatcher(oFilter))
-        Next
-    End Sub
-
-    Private Function CreateWatcher(Filter As String)
-        Dim oWatcher = New FileSystemWatcher() With {
-            .Path = _Path,
-            .Filter = Filter,
-            .NotifyFilter = NotifyFilters.CreationTime _
-                            Or NotifyFilters.LastAccess _
-                            Or NotifyFilters.LastWrite _
-                            Or NotifyFilters.Size _
-                            Or NotifyFilters.FileName _
-                            Or NotifyFilters.Attributes
-        }
-
-        AddHandler oWatcher.Created, AddressOf HandleFileCreated
-        AddHandler oWatcher.Changed, AddressOf HandleFileChanged
-        AddHandler oWatcher.Deleted, AddressOf HandleFileDeleted
-        AddHandler oWatcher.Renamed, AddressOf HandleFileRenamed
-
-        Return oWatcher
-    End Function
-
-    Private Sub HandleFileCreated(sender As Object, e As FileSystemEventArgs)
-        _Files.Add(e.FullPath, New FileProperties())
-        _Logger.Info("[Created] " & e.FullPath)
-    End Sub
-    Private Sub HandleFileChanged(sender As Object, e As FileSystemEventArgs)
-        _Files.Item(e.FullPath).ChangedAt = DateTime.Now
-        _Logger.Info("[Changed] " & e.FullPath)
-    End Sub
-    Private Sub HandleFileDeleted(sender As Object, e As FileSystemEventArgs)
-        _Files.Remove(e.FullPath)
-        _Logger.Info("[Removed] " & e.FullPath)
-    End Sub
-
-    Private Sub HandleFileRenamed(sender As Object, e As RenamedEventArgs)
-        Dim oProperties = _Files.Item(e.OldFullPath)
-        _Files.Remove(e.OldFullPath)
-        _Files.Add(e.FullPath, oProperties)
-        ' Soll eine umbenannte datei als NEU gelten?
-
-        _Logger.Info("[Renamed] {0} --> {1}", e.OldFullPath, e.FullPath)
-    End Sub
-
     Public Sub Start()
         For Each oWatcher In _Watchers
             oWatcher.EnableRaisingEvents = True
@@ -98,13 +58,75 @@ Public Class FileWatcher
         Next
     End Sub
 
-    Public Class FileProperties
+    Private Function GetDefaultFilters()
-        Public CreatedAt As DateTime
+        Return New List(Of BaseFileFilter) From {
-        Public ChangedAt As DateTime
+              New TempFileFilter,
+              New OfficeFileFilter
+        }
+    End Function
 
-        Public Sub New()
+    Private Function CreateWatcher(Filter As String)
-            CreatedAt = DateTime.Now
+        Dim oWatcher = New FileSystemWatcher() With {
-            ChangedAt = Nothing
+            .Path = _Path,
+            .Filter = Filter,
+            .NotifyFilter = NotifyFilters.LastAccess _
+                            Or NotifyFilters.LastWrite _
+                            Or NotifyFilters.FileName _
+                            Or NotifyFilters.Size _
+                            Or NotifyFilters.FileName _
+                            Or NotifyFilters.Attributes
+        }
+
+        AddHandler oWatcher.Created, AddressOf HandleFileCreated
+        AddHandler oWatcher.Changed, AddressOf HandleFileChanged
+        AddHandler oWatcher.Deleted, AddressOf HandleFileDeleted
+        AddHandler oWatcher.Renamed, AddressOf HandleFileRenamed
+
+        Return oWatcher
+    End Function
+
+    Private Sub HandleFileCreated(sender As Object, e As FileSystemEventArgs)
+        _Files.Add(e.FullPath, New FileWatcherProperties())
+        _Logger.Debug("[Created] " & e.FullPath)
     End Sub
-    End Class
+
+    ''' <summary>
+    ''' This may fire twice for a single save operation, 
+    ''' see: https://blogs.msdn.microsoft.com/oldnewthing/20140507-00/?p=1053/
+    ''' </summary>
+    Private Sub HandleFileChanged(sender As Object, e As FileSystemEventArgs)
+        _Files.Item(e.FullPath).ChangedAt = DateTime.Now
+        _Logger.Debug("[Changed] " & e.FullPath)
+
+        Dim oShouldRaiseSave As Boolean = Not _Filters.Any(Function(oFilter)
+                                                               Return oFilter.ShouldFilter(e)
+                                                           End Function)
+
+        If oShouldRaiseSave Then
+            RaiseEvent FileSaved(e.FullPath, False)
+        End If
+    End Sub
+    Private Sub HandleFileDeleted(sender As Object, e As FileSystemEventArgs)
+        _Files.Remove(e.FullPath)
+        _Logger.Debug("[Removed] " & e.FullPath)
+    End Sub
+
+    Private Sub HandleFileRenamed(sender As Object, e As RenamedEventArgs)
+        Dim oProperties = _Files.Item(e.OldFullPath)
+        _Files.Remove(e.OldFullPath)
+        _Files.Add(e.FullPath, oProperties)
+        ' Soll eine umbenannte datei als NEU gelten?
+
+        Dim oShouldRaiseSave = _Filters.Any(Function(oFilter)
+                                                Return oFilter.ShouldRaiseSave(e)
+                                            End Function)
+
+        If oShouldRaiseSave Then
+            RaiseEvent FileSaved(e.OldFullPath, True)
+        End If
+
+        _Logger.Debug("[Renamed] {0} --> {1}", e.OldFullPath, e.FullPath)
+    End Sub
+
+
 End Class

Filesystem/FileWatcherFilters.vb

@@ -0,0 +1,61 @@
+Imports System.IO
+
+''' <summary>
+''' Built-in filters for FileWatcher that are useful for correctly detecting changes on Office documents (currently Office 2016)
+''' </summary>
+Public Class FileWatcherFilters
+    ''' <summary>
+    ''' Base Filter that all filters must inherit from
+    ''' Provides two functions that may be overridden and some useful file extension lists
+    ''' </summary>
+    Public MustInherit Class BaseFileFilter
+        Public TempFiles As New List(Of String) From {".tmp", ""}
+
+        Public Overridable Function ShouldFilter(e As FileSystemEventArgs) As Boolean
+            Return False
+        End Function
+        Public Overridable Function ShouldRaiseSave(e As RenamedEventArgs) As Boolean
+            Return False
+        End Function
+    End Class
+
+    ''' <summary>
+    ''' Simple Filter that filters changes made on temporary files
+    ''' </summary>
+    Public Class TempFileFilter
+        Inherits BaseFileFilter
+
+        Public Overrides Function ShouldFilter(e As FileSystemEventArgs) As Boolean
+            Dim oFileInfo As New FileInfo(e.FullPath)
+            Return TempFiles.Contains(oFileInfo.Extension)
+        End Function
+    End Class
+
+    ''' <summary>
+    ''' Filter to detect changes on Office files
+    ''' </summary>
+    Public Class OfficeFileFilter
+        Inherits BaseFileFilter
+
+        Public OfficeFiles As New List(Of String) From {".docx", ".pptx", ".xlsx"}
+
+        Public Overrides Function ShouldFilter(e As FileSystemEventArgs) As Boolean
+            Dim oFileInfo As New FileInfo(e.FullPath)
+            Return OfficeFiles.Contains(oFileInfo.Extension) And oFileInfo.Name.StartsWith("~")
+        End Function
+
+        Public Overrides Function ShouldRaiseSave(e As RenamedEventArgs) As Boolean
+            Dim oIsTransform = OfficeFiles.Any(Function(Extension As String)
+                                                   Return e.OldName.EndsWith(Extension)
+                                               End Function)
+
+            ' Check if it is renamed to a temp file
+            Dim oIsTempFile = TempFiles.Any(Function(Extension)
+                                                Return e.Name.EndsWith(Extension)
+                                            End Function)
+
+
+            Return oIsTransform And oIsTempFile
+        End Function
+    End Class
+End Class

Filesystem/FileWatcherProperties.vb

@@ -0,0 +1,10 @@
+Public Class FileWatcherProperties
+    Public Property CreatedAt As DateTime
+    Public Property ChangedAt As DateTime
+    Public ReadOnly Property HasChanged As Boolean
+    Public Sub New()
+        CreatedAt = DateTime.Now
+        ChangedAt = Nothing
+        HasChanged = False
+    End Sub
+End Class

Filesystem/Filesystem.vbproj

@@ -81,6 +81,8 @@
     <Compile Include="File.vb" />
     <Compile Include="FileContainerInner.vb" />
     <Compile Include="FileWatcher.vb" />
+    <Compile Include="FileWatcherFilters.vb" />
+    <Compile Include="FileWatcherProperties.vb" />
     <Compile Include="My Project\AssemblyInfo.vb" />
     <Compile Include="My Project\Application.Designer.vb">
       <AutoGen>True</AutoGen>

TestGUI/FolderWatcher.vb

@@ -1,30 +1,37 @@
 Imports System.ComponentModel
 Imports System.IO
 Imports DigitalData.Modules.Filesystem
+Imports DigitalData.Modules.Filesystem.FileWatcherFilters
 Imports DigitalData.Modules.Logging
 
 Public Class FolderWatcher
 
     Private _LogConfig As LogConfig
+    Private _Logger As Logger
     Private _Watcher As FileWatcher
 
-    Public Sub FileCreated(_sender As Object, _e As FileSystemEventArgs)
+    <STAThread()>
-        ListBox1.Items.Add($"File created: {_e.FullPath}")
-    End Sub
-
-    Public Sub FileChanged(_sender As Object, _e As FileSystemEventArgs)
-        ListBox1.Items.Add($"File changed: {_e.FullPath}")
-    End Sub
-
     Private Sub FolderWatcher_Load(sender As Object, e As EventArgs) Handles Me.Load
         _LogConfig = New LogConfig(LogConfig.PathType.CurrentDirectory, Nothing, "MAIN")
-        _Watcher = New FileWatcher(_LogConfig, "E:\Watcher")
+        _LogConfig.Debug = True
+        _Logger = _LogConfig.GetLogger()
+        Dim oFilters As New List(Of BaseFileFilter) From {
+            New TempFileFilter,
+            New OfficeFileFilter
+        }
+        _Watcher = New FileWatcher(_LogConfig, "E:\Watcher", oFilters)
 
         _Watcher.Add("*.*")
 
+        AddHandler _Watcher.FileSaved, AddressOf HandleFileSaved
+
         _Watcher.Start()
     End Sub
 
+    Private Sub HandleFileSaved(FullName As String, IsSpecial As Boolean)
+        _Logger.Info("{1}File Saved: {0}", FullName, IIf(IsSpecial, "Special ", ""))
+    End Sub
+
     Private Sub FolderWatcher_Closing(sender As Object, e As CancelEventArgs) Handles Me.Closing
         _Watcher.Stop()
     End Sub