Safe(r)Delete, Safe(r)Move : could have infinite loop of exceptions. Fixed. Limit 3

AaxDecrypter/AaxcDownloadConverter.cs

@@ -65,7 +65,7 @@ namespace AaxDecrypter
         {
             var zeroProgress = Step2_Start();
 
-            FileUtility.SafeDelete(OutputFileName);
+            FileUtility.SaferDelete(OutputFileName);
 
             var outputFile = File.Open(OutputFileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
 
@@ -202,7 +202,7 @@ That naming may not be desirable for everyone, but it's an easy change to instea
             var fileName = FileUtility.GetMultipartFileName(OutputFileName, currentChapter, splitChapters.Count, newSplitCallback.Chapter.Title);
 			multiPartFilePaths.Add(fileName);
 
-            FileUtility.SafeDelete(fileName);
+            FileUtility.SaferDelete(fileName);
 
             newSplitCallback.OutputFile = File.Open(fileName, FileMode.OpenOrCreate);
 		}

AaxDecrypter/AudiobookDownloadBase.cs

@@ -47,7 +47,7 @@ namespace AaxDecrypter
 			CacheDir = cacheDirectory;
 
 			// delete file after validation is complete
-			FileUtility.SafeDelete(OutputFileName);
+			FileUtility.SaferDelete(OutputFileName);
 			DownloadLicense = ArgumentValidator.EnsureNotNull(dlLic, nameof(dlLic));
 		}
 
@@ -116,8 +116,8 @@ namespace AaxDecrypter
 
 		protected bool Step4_Cleanup()
 		{
-			FileUtility.SafeDelete(jsonDownloadState);
+			FileUtility.SaferDelete(jsonDownloadState);
-			FileUtility.SafeDelete(tempFile);
+			FileUtility.SaferDelete(tempFile);
 			return !IsCanceled;
 		}
 
@@ -136,8 +136,8 @@ namespace AaxDecrypter
 			}
 			catch
 			{
-				FileUtility.SafeDelete(jsonDownloadState);
+				FileUtility.SaferDelete(jsonDownloadState);
-				FileUtility.SafeDelete(tempFile);
+				FileUtility.SaferDelete(tempFile);
 				return NewNetworkFilePersister();
 			}
 		}

AppScaffolding/AppScaffolding.csproj

@@ -3,7 +3,7 @@
 
   <PropertyGroup>
     <TargetFramework>net5.0</TargetFramework>
-    <Version>6.2.6.7</Version>
+    <Version>6.2.6.8</Version>
   </PropertyGroup>
 
   <ItemGroup>

FileManager/FileManager.csproj

@@ -6,6 +6,7 @@
 
   <ItemGroup>
     <PackageReference Include="Dinah.Core" Version="2.0.0.1" />
+    <PackageReference Include="Polly" Version="7.2.2" />
   </ItemGroup>
 
 </Project>

FileManager/FileUtility.cs

@@ -3,6 +3,8 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Dinah.Core;
+using Polly;
+using Polly.Retry;
 
 namespace FileManager
 {
@@ -11,8 +13,7 @@ namespace FileManager
         private const int MAX_FILENAME_LENGTH = 255;
         private const int MAX_DIRECTORY_LENGTH = 247;
 
-//public static string GetValidFilename(string template, Dictionary<string, object> parameters) { }
+        public static string GetValidFilename(string dirFullPath, string filename, string extension, string metadataSuffix)
-        public static string GetValidFilename(string dirFullPath, string filename, string extension, params string[] metadataSuffixes)
         {
             if (string.IsNullOrWhiteSpace(dirFullPath))
                 throw new ArgumentException($"{nameof(dirFullPath)} may not be null or whitespace", nameof(dirFullPath));
@@ -23,13 +24,11 @@ namespace FileManager
             filename = filename.Replace(':', '_');
             filename = PathLib.ToPathSafeString(filename);
 
-            // manage length
             if (filename.Length > 50)
                 filename = filename.Substring(0, 50) + "[...]";
 
-            // append metadata
+            if (!string.IsNullOrWhiteSpace(metadataSuffix))
-            if (metadataSuffixes != null && metadataSuffixes.Length > 0)
+                filename += $" [{metadataSuffix}]";
-                filename += " [" + string.Join("][", metadataSuffixes) + "]";
 
             // extension is null when this method is used for directory names
             if (!string.IsNullOrWhiteSpace(extension))
@@ -65,7 +64,7 @@ namespace FileManager
         public static string Move(string source, string destination)
         {
             // TODO: destination must be valid path. Use: " (#)" when needed
-            SafeMove(source, destination);
+            SaferMove(source, destination);
             return destination;
         }
 
@@ -75,57 +74,50 @@ namespace FileManager
             return path;
 		}
 
-        /// <summary>Delete file. No error when file does not exist.
+        private static int maxRetryAttempts { get; } = 3;
-        /// Exceptions are logged, not thrown.</summary>
+        private static TimeSpan pauseBetweenFailures { get; } = TimeSpan.FromMilliseconds(100);
-        /// <param name="source">File to delete</param>
+        private static RetryPolicy retryPolicy { get; } =
-        public static void SafeDelete(string source)
+            Policy
-        {
+            .Handle<Exception>()
-            if (!File.Exists(source))
+            .WaitAndRetry(maxRetryAttempts, i => pauseBetweenFailures);
-                return;
 
-            while (true)
+        /// <summary>Delete file. No error when source does not exist. Retry up to 3 times.</summary>
+        public static void SaferDelete(string source)
+            => retryPolicy.Execute(() =>
             {
                 try
                 {
-                    File.Delete(source);
+                    if (!File.Exists(source))
-                    Serilog.Log.Logger.Information($"File successfully deleted: {source}");
-                    break;
-                }
-                catch (Exception e)
-                {
-					System.Threading.Thread.Sleep(100);
-                    Serilog.Log.Logger.Error(e, $"Failed to delete: {source}");
-                }
-            }
-        }
-
-        /// <summary>
-		/// Moves a specified file to a new location, providing the option to specify a newfile name.
-		/// Exceptions are logged, not thrown.
-		/// </summary>
-		/// <param name="source">The name of the file to move. Can include a relative or absolute path.</param>
-		/// <param name="target">The new path and name for the file.</param>
-		public static void SafeMove(string source, string target)
-        {
-            while (true)
-            {
-                try
-                {
-                    if (File.Exists(source))
                     {
-                        SafeDelete(target);
+                        File.Delete(source);
-                        File.Move(source, target);
+                        Serilog.Log.Logger.Information("File successfully deleted", new { source });
-                        Serilog.Log.Logger.Information($"File successfully moved from '{source}' to '{target}'");
                     }
-
-                    break;
                 }
                 catch (Exception e)
                 {
-					System.Threading.Thread.Sleep(100);
+                    Serilog.Log.Logger.Error(e, "Failed to delete file", new { source });
-                    Serilog.Log.Logger.Error(e, $"Failed to move '{source}' to '{target}'");
+                    throw;
                 }
-            }
+            });
-        }
+
+        /// <summary>Move file. No error when source does not exist. Retry up to 3 times.</summary>
+		public static void SaferMove(string source, string target)
+            => retryPolicy.Execute(() =>
+            {
+                try
+                {
+                    if (!File.Exists(source))
+                    {
+                        SaferDelete(target);
+                        File.Move(source, target);
+                        Serilog.Log.Logger.Information("File successfully moved", new { source, target });
+                    }
+                }
+                catch (Exception e)
+                {
+                    Serilog.Log.Logger.Error(e, "Failed to move file", new { source, target });
+                    throw;
+                }
+            });
     }
 }

LibationFileManager/LibationFileManager.csproj

@@ -4,11 +4,6 @@
     <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
-  <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="5.0.0" />
-    <PackageReference Include="Polly" Version="7.2.2" />
-  </ItemGroup>
-
   <ItemGroup>
     <ProjectReference Include="..\FileManager\FileManager.csproj" />
   </ItemGroup>