ConfigManager: Test write access for config paths

Filesystem/File.vb

@@ -24,6 +24,8 @@ Public Class File
     Private ReadOnly _logger As Logger
     Private ReadOnly _logConfig As LogConfig
 
+    Private Const FILE_NAME_ACCESS_TEST = "accessTest.txt"
+
     Public Sub New(LogConfig As LogConfig)
         _logConfig = LogConfig
         _logger = LogConfig.GetLogger()
@@ -94,6 +96,55 @@ Public Class File
         IO.File.Move(FilePath, Path.Combine(Directory, oFileInfo.Name))
     End Sub
 
+    ''' <summary>
+    ''' Tries to create a directory and returns its path.
+    ''' Returns a temp path if `DirectoryPath` can not be created or written to.
+    ''' </summary>
+    ''' <param name="DirectoryPath">The directory to create</param>
+    ''' <param name="TestWriteAccess">Should a write access test be performed?</param>
+    ''' <returns>The used path</returns>
+    Public Function CreateDirectory(DirectoryPath As String, Optional TestWriteAccess As Boolean = True) As String
+        Dim oFinalPath As String
+        If Directory.Exists(DirectoryPath) Then
+            _logger.Debug("Directory {0} already exists. Skipping.", DirectoryPath)
+            oFinalPath = DirectoryPath
+        Else
+            Try
+                Directory.CreateDirectory(DirectoryPath)
+                oFinalPath = DirectoryPath
+            Catch ex As Exception
+                _logger.Error(ex)
+                _logger.Warn("Directory {0} could not be created. Temp path will be used instead.", DirectoryPath)
+                oFinalPath = Path.GetTempPath()
+            End Try
+        End If
+
+        If TestWriteAccess AndAlso Not TestPathIsWritable(DirectoryPath) Then
+            _logger.Warn("Directory {0} is not writable. Temp path will be used instead.", DirectoryPath)
+            oFinalPath = Path.GetTempPath()
+        Else
+            oFinalPath = DirectoryPath
+        End If
+
+        _logger.Debug("Using path {0}", oFinalPath)
+
+        Return oFinalPath
+    End Function
+
+    Public Function TestPathIsWritable(DirectoryPath As String) As Boolean
+        Try
+            Dim fileAccessPath = Path.Combine(DirectoryPath, FILE_NAME_ACCESS_TEST)
+            Using fs As FileStream = IO.File.Create(fileAccessPath)
+                fs.WriteByte(0)
+            End Using
+
+            IO.File.Delete(fileAccessPath)
+            Return True
+        Catch ex As Exception
+            Return False
+        End Try
+    End Function
+
     Public Function TestPathIsDirectory(Path As String) As Boolean
         If Not Directory.Exists(Path) Then
             Return False

Filesystem/Filesystem.vbproj

@@ -79,7 +79,9 @@
     <Compile Include="DocumentObject.vb" />
     <Compile Include="FileContainer.vb" />
     <Compile Include="Encryption.vb" />
-    <Compile Include="File.vb" />
+    <Compile Include="File.vb">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Compile>
     <Compile Include="FileContainerInner.vb" />
     <Compile Include="FileWatcher.vb" />
     <Compile Include="FileWatcherFilters.vb" />

Modules.Config/ConfigManager.vb

@@ -11,8 +11,8 @@ Public Class ConfigManager(Of T)
     Private ReadOnly _LogConfig As LogConfig
     Private ReadOnly _Logger As Logger
     Private ReadOnly _File As Filesystem.File
-    Private ReadOnly _UserPath As String
+    Private ReadOnly _UserDirectory As String
-    Private ReadOnly _ComputerPath As String
+    Private ReadOnly _ComputerDirectory As String
     Private ReadOnly _TestMode As Boolean = False
 
     Private ReadOnly _Blueprint As T
@@ -33,17 +33,17 @@ Public Class ConfigManager(Of T)
     ''' <returns></returns>
     Public ReadOnly Property Config As T
 
+    ''' <summary>
+    ''' Path to the current user config.
+    ''' </summary>
+    ''' <returns></returns>
     Public ReadOnly Property UserConfigPath As String
-        Get
-            Return _UserPath
-        End Get
-    End Property
 
+    ''' <summary>
+    ''' Path to the current computer config. Maybe the same as `UserConfigPath`
+    ''' </summary>
+    ''' <returns></returns>
     Public ReadOnly Property ComputerConfigPath As String
-        Get
-            Return _ComputerPath
-        End Get
-    End Property
 
     ''' <summary>
     ''' Creates a new instance of the ConfigManager
@@ -58,35 +58,18 @@ Public Class ConfigManager(Of T)
         _Logger = LogConfig.GetLogger()
         _File = New Filesystem.File(_LogConfig)
 
-        _UserPath = Path.Combine(UserConfigPath, USER_CONFIG_NAME)
-        _ComputerPath = Path.Combine(ComputerConfigPath, COMPUTER_CONFIG_NAME)
-        _ForceUserConfig = ForceUserConfig
-
         _Blueprint = Activator.CreateInstance(Of T)
         _BlueprintType = _Blueprint.GetType
         _Serializer = New XmlSerializer(_BlueprintType)
 
-        If Not Directory.Exists(UserConfigPath) Then
+        _UserDirectory = _File.CreateDirectory(UserConfigPath)
-            _Logger.Debug("UserConfigPath {0} did not exist and was created", UserConfigPath)
+        _ComputerDirectory = _File.CreateDirectory(ComputerConfigPath)
-            Directory.CreateDirectory(UserConfigPath)
+        _ForceUserConfig = ForceUserConfig
-        End If
 
-        If Not _File.TestPathIsDirectory(UserConfigPath) Then
+        UserConfigPath = Path.Combine(_UserDirectory, USER_CONFIG_NAME)
-            _Logger.Warn("UserConfigPath {0} is not a directory", UserConfigPath)
+        ComputerConfigPath = Path.Combine(_ComputerDirectory, COMPUTER_CONFIG_NAME)
-            Throw New ArgumentException($"Path {UserConfigPath} is not a directory!")
-        End If
 
-        If Not Directory.Exists(ComputerConfigPath) Then
+        Config = LoadConfig()
-            _Logger.Debug("ComputerConfigPath {0} did not exist and was created", ComputerConfigPath)
-            Directory.CreateDirectory(ComputerConfigPath)
-        End If
-
-        If Not _File.TestPathIsDirectory(ComputerConfigPath) Then
-            _Logger.Warn("ComputerConfigPath {0} is not a directory", ComputerConfigPath)
-            Throw New ArgumentException($"Path {ComputerConfigPath} is not a directory!")
-        End If
-
-        _Config = LoadConfig()
     End Sub
 
     ''' <summary>
@@ -105,7 +88,7 @@ Public Class ConfigManager(Of T)
     ''' <returns>True if save was successful, False otherwise</returns>
     Public Function Save(Optional ForceAll As Boolean = False) As Boolean
         Try
-            WriteToFile(_Config, _UserPath, ForceAll)
+            WriteToFile(Config, UserConfigPath, ForceAll)
             Return True
         Catch ex As Exception
             _Logger.Error(ex)
@@ -169,9 +152,9 @@ Public Class ConfigManager(Of T)
 
 
     Private Function LoadComputerConfig(ByVal Config As T) As T
-        If File.Exists(_ComputerPath) Then
+        If File.Exists(ComputerConfigPath) Then
             Try
-                Dim oComputerConfig = ReadFromFile(_ComputerPath)
+                Dim oComputerConfig = ReadFromFile(ComputerConfigPath)
                 CopyValues(oComputerConfig, Config)
             Catch ex As Exception
                 _Logger.Error(ex)
@@ -186,9 +169,9 @@ Public Class ConfigManager(Of T)
     End Function
 
     Private Function LoadUserConfig(ByVal Config As T) As T
-        If File.Exists(_UserPath) Then
+        If File.Exists(UserConfigPath) Then
             Try
-                Dim oUserConfig = ReadFromFile(_UserPath)
+                Dim oUserConfig = ReadFromFile(UserConfigPath)
 
                 ' if user config exists
                 If Not IsNothing(oUserConfig) Then