Merge pull request #592 from LogExperts/568-stop-following-tail-after-file-re-creation

568 stop following tail after file re creation

Author: Hirogen

.vscode/settings.json

@@ -15,5 +15,7 @@
             "matchCommandLine": true
         },
         "git rev-parse": true
-    }
+    },
+    "dotnet.preferCSharpExtension": true,
+    "dotnet.defaultSolution": "src/LogExpert.sln"
 }

src/PluginRegistry/PluginHashGenerator.Generated.cs

@@ -10,35 +10,35 @@ public static partial class PluginValidator
 {
     /// <summary>
     /// Gets pre-calculated SHA256 hashes for built-in plugins.
-    /// Generated: 2026-05-28 19:52:00 UTC
+    /// Generated: 2026-06-01 09:31:40 UTC
     /// Configuration: Release
     /// Plugin count: 21
     /// </summary>
     public static Dictionary<string, string> GetBuiltInPluginHashes()
     {
         return new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
         {
-                         ["AutoColumnizer.dll"] = "EDF4B48F71CF2192A99F63B9FE493661521A2E671D9185CCEB181B513DF0C1A5",
+                         ["AutoColumnizer.dll"] = "1E5C3388943F4EB34382324E6A2C54F93C89B88CFE1D69ACF1203FB7416E672F",
             ["BouncyCastle.Cryptography.dll"] = "E5EEAF6D263C493619982FD3638E6135077311D08C961E1FE128F9107D29EBC6",
             ["BouncyCastle.Cryptography.dll (x86)"] = "E5EEAF6D263C493619982FD3638E6135077311D08C961E1FE128F9107D29EBC6",
-            ["CsvColumnizer.dll"] = "397CCA331A6FD1687C8CBDF78DF6DF9C080B7A16860C511F2DC0E275A5257C4F",
-            ["CsvColumnizer.dll (x86)"] = "397CCA331A6FD1687C8CBDF78DF6DF9C080B7A16860C511F2DC0E275A5257C4F",
-            ["DefaultPlugins.dll"] = "58B2ED626556C1B0E1B02D62DF0A0658618FA05B309BFAA2C2582B180594B7E6",
-            ["FlashIconHighlighter.dll"] = "0861244E3F7B52D44B8487732724E277658143E5940AACFF977AA74048FF1B9D",
-            ["GlassfishColumnizer.dll"] = "B75D7808007E9CA1235E282B07431C70A16D378B647B58BAEE605075D7B8FF08",
-            ["JsonColumnizer.dll"] = "A469FEC6C1E6F7B209D960CE7C3416CF80EFD5A2A062BCAD7B0E8AE6A3988ABF",
-            ["JsonCompactColumnizer.dll"] = "F6735973634AE8A986BC9FD8B89F8817D36458E488B6A7BCD2320883DD4BA5BC",
-            ["Log4jXmlColumnizer.dll"] = "D148D1FEC9A0152714AAE8CBAB0A9BDDF9ACFBFED3FF0CEB8D5966908DC24760",
-            ["LogExpert.Resources.dll"] = "A25FDA182EECF5BCC828C0C3F145FD774530980E9C72AC17591043677FA9E201",
+            ["CsvColumnizer.dll"] = "0DB8949CCFB20468D5C934474EEC98B3BD1AD0802D2F79F9DF9013DAF2A037C9",
+            ["CsvColumnizer.dll (x86)"] = "0DB8949CCFB20468D5C934474EEC98B3BD1AD0802D2F79F9DF9013DAF2A037C9",
+            ["DefaultPlugins.dll"] = "FE68CE75E429D0F29ABB2D221A4BBBC16AD6C06B77FB2B709134591F276DE9DF",
+            ["FlashIconHighlighter.dll"] = "A8C733BBA980A364B3739EFBF866E85E166C15B79A6B704456C7F92884BECB27",
+            ["GlassfishColumnizer.dll"] = "86D49BC1EAC7F843893134F7F5B64BE37A94C914F389DB56598DBC670D849835",
+            ["JsonColumnizer.dll"] = "6A6B27428F647DF29D03F4F17AED89DDF1FF24636B59644FBD12FB3D92A26F18",
+            ["JsonCompactColumnizer.dll"] = "04A7169C087181B49189AB8DD9C9FB260189EB1CF394452EA02987FFE6934794",
+            ["Log4jXmlColumnizer.dll"] = "301E7805F9BA5BA211256119636B7A8D34848475C5B7885737FD8E61CB1B5233",
+            ["LogExpert.Resources.dll"] = "A2AFABDCFDA0B558426706336C11FB8B02770383419BA1E0192FFFEBEB091A38",
             ["Microsoft.Extensions.DependencyInjection.Abstractions.dll"] = "67FA4325000DB017DC0C35829B416F024F042D24EFB868BCF17A895EE6500A93",
             ["Microsoft.Extensions.DependencyInjection.Abstractions.dll (x86)"] = "67FA4325000DB017DC0C35829B416F024F042D24EFB868BCF17A895EE6500A93",
             ["Microsoft.Extensions.Logging.Abstractions.dll"] = "BB853130F5AFAF335BE7858D661F8212EC653835100F5A4E3AA2C66A4D4F685D",
             ["Microsoft.Extensions.Logging.Abstractions.dll (x86)"] = "BB853130F5AFAF335BE7858D661F8212EC653835100F5A4E3AA2C66A4D4F685D",
-            ["RegexColumnizer.dll"] = "C0DC4D43DB02C2015A490BC4C62549D7CDD1B107C6944F20DB0B4C4285371288",
-            ["SftpFileSystem.dll"] = "AAD426FB4E53916B8B26F427374EA3E6706B940564F4CD0E059E69A613CBE02B",
-            ["SftpFileSystem.dll (x86)"] = "6FEC9B0EC9B9241ACA09999C55AD96F33FD52A2A1A14DC513D06BC42BF2C1B86",
-            ["SftpFileSystem.Resources.dll"] = "0F8C4D65FE7E8A79A11DF521116E36E65AC28DE732C67264A3790AD2F1E4CBB8",
-            ["SftpFileSystem.Resources.dll (x86)"] = "0F8C4D65FE7E8A79A11DF521116E36E65AC28DE732C67264A3790AD2F1E4CBB8",
+            ["RegexColumnizer.dll"] = "AC1E977392AD7A291174C357211480121C49898C2258E8608E06AF8DDA48DE7E",
+            ["SftpFileSystem.dll"] = "E5B7DD9D7038F68B501BD8398141FD6E8EBE9878B205D346E3C36FCD40DA9CA8",
+            ["SftpFileSystem.dll (x86)"] = "8B892CC370EE3E01693F282C32245B55F3D225F48D6631102EB2DC79692F762B",
+            ["SftpFileSystem.Resources.dll"] = "20CFD22D83D1581FF63348F3F0D3E824A73887F80BCDEB04E6AAF3E5A200C036",
+            ["SftpFileSystem.Resources.dll (x86)"] = "20CFD22D83D1581FF63348F3F0D3E824A73887F80BCDEB04E6AAF3E5A200C036",
 
         };
     }

src/tools/LogRotator/LogRotator.cs

@@ -35,16 +35,31 @@
 Console.WriteLine($"Control characters in output: {(includeControlChars ? "ENABLED" : "disabled")}");
 Console.WriteLine("Press ENTER to perform a rotation (with oldest file deletion).");
 Console.WriteLine("Press A to append a single live line (no rotation) for tail testing.");
+Console.WriteLine("Press D to delete the log, wait, then recreate it AND start a 25 lines/s");
+Console.WriteLine("  background writer (repro for issue #568). Press D again to delete mid-stream.");
+Console.WriteLine("Press F to flicker: delete, wait, briefly recreate, delete again mid-reload,");
+Console.WriteLine("  wait, then recreate + writer. Tries to land LogExpert's new reader's");
+Console.WriteLine("  ReadFiles inside a deletion window.");
 Console.WriteLine("Press Q to quit.");
 
 var rotationCount = 0;
+var delayedDeleteCount = 0;
+var flickerCount = 0;
+const int delayedDeleteSeconds = 5;
+const int liveWriterDelayMs = 40; // ~25 lines/s
+const int flickerInitialAbsentMs = 5000;
+const int flickerBriefVisibleMs = 200;
+const int flickerSecondAbsentMs = 2500;
+CancellationTokenSource? liveWriterCts = null;
+Task? liveWriterTask = null;
 
 while (true)
 {
     var key = Console.ReadKey(true);
 
     if (key.Key == ConsoleKey.Q)
     {
+        StopLiveWriter();
         break;
     }
 
@@ -54,6 +69,20 @@
         continue;
     }
 
+    if (key.Key == ConsoleKey.D)
+    {
+        delayedDeleteCount++;
+        DelayedDelete(Path.Join(baseDir, safeBaseName), delayedDeleteCount, delayedDeleteSeconds);
+        continue;
+    }
+
+    if (key.Key == ConsoleKey.F)
+    {
+        flickerCount++;
+        FlickerRepro(Path.Join(baseDir, safeBaseName), flickerCount);
+        continue;
+    }
+
     if (key.Key != ConsoleKey.Enter)
     {
         continue;
@@ -131,6 +160,149 @@ void AppendLiveLine(string path)
     Console.WriteLine($"  Appended live line to {name} ({new FileInfo(path).Length} bytes total)");
 }
 
+// Repro path for issue #568: stop any background writer, delete the file and
+// keep it absent long enough (> LogExpert's 1.25s OpenStream retry budget) for
+// the watcher to enter FileNotFound state, then recreate it AND start a
+// continuous background writer (~25 lines/s). The next D press will delete the
+// file while the writer is actively appending — that mid-stream delete is the
+// scenario the reporter describes.
+void DelayedDelete(string path, int iteration, int delaySeconds)
+{
+    var name = Path.GetFileName(path);
+    Console.WriteLine($"\n--- Delete + delay + recreate #{iteration} ---");
+
+    StopLiveWriter();
+
+    if (File.Exists(path))
+    {
+        File.Delete(path);
+        Console.WriteLine($"  Deleted: {name}");
+    }
+    else
+    {
+        Console.WriteLine($"  {name} was already missing.");
+    }
+
+    Console.WriteLine($"  File absent. Waiting {delaySeconds}s so LogExpert enters FileNotFound state...");
+    for (var i = delaySeconds; i > 0; i--)
+    {
+        Console.Write($"\r  Countdown: {i}s ");
+        Thread.Sleep(1000);
+    }
+    Console.WriteLine("\r  Countdown: done.");
+
+    WriteLogFile(path, fileId: 900 + iteration);
+    Console.WriteLine($"  Recreated {name} with {linesPerFile} lines ({new FileInfo(path).Length} bytes).");
+    StartLiveWriter(path, iteration);
+    Console.WriteLine($"  Background writer started (~{1000 / liveWriterDelayMs} lines/s).");
+    Console.WriteLine("  Watch LogExpert: lines should keep appearing.");
+    Console.WriteLine("  If they do NOT, the bug is reproduced. Press D again to delete mid-stream.");
+}
+
+// Tighter race than DelayedDelete: after the file has been absent long enough
+// for LogExpert to enter FileNotFound, we briefly recreate it (so the watcher
+// fires OnRespawned and the LogWindow schedules a Reload), then delete it
+// again before the new LogfileReader's first ReadFiles completes its
+// OpenStream retries (5 x 250ms = 1.25s). If the hypothesis about issue #568
+// is correct, the new reader's ReadFiles catches IOException, _isDeleted is
+// set, ReportLoadingFinished is skipped, and FileSizeChanged never gets wired
+// up. After we recreate the file for real and start the writer, those writes
+// should fail to propagate.
+void FlickerRepro(string path, int iteration)
+{
+    var name = Path.GetFileName(path);
+    Console.WriteLine($"\n--- Flicker repro #{iteration} ---");
+
+    StopLiveWriter();
+
+    if (File.Exists(path))
+    {
+        File.Delete(path);
+        Console.WriteLine($"  Deleted: {name}");
+    }
+
+    Console.WriteLine($"  Phase 1: file absent for {flickerInitialAbsentMs / 1000.0:0.0}s (LogExpert -> FileNotFound)");
+    Thread.Sleep(flickerInitialAbsentMs);
+
+    WriteLogFile(path, fileId: 700 + iteration);
+    Console.WriteLine($"  Phase 2: briefly visible ({flickerBriefVisibleMs}ms) - LogExpert schedules a Reload");
+    Thread.Sleep(flickerBriefVisibleMs);
+
+    File.Delete(path);
+    Console.WriteLine($"  Phase 3: deleted again, absent {flickerSecondAbsentMs / 1000.0:0.0}s");
+    Console.WriteLine($"           (exceeds 1.25s OpenStream retry budget - new reader's ReadFiles should fail)");
+    Thread.Sleep(flickerSecondAbsentMs);
+
+    WriteLogFile(path, fileId: 750 + iteration);
+    Console.WriteLine($"  Phase 4: recreated with {linesPerFile} lines, starting writer.");
+    StartLiveWriter(path, iteration);
+    Console.WriteLine("  Watch LogExpert. If row count freezes, bug reproduced.");
+}
+
+void StartLiveWriter(string path, int iteration)
+{
+    StopLiveWriter();
+    liveWriterCts = new CancellationTokenSource();
+    var token = liveWriterCts.Token;
+    var fileId = 800 + iteration;
+    liveWriterTask = Task.Run(() => LiveWriterLoop(path, fileId, token));
+}
+
+void StopLiveWriter()
+{
+    if (liveWriterCts == null)
+    {
+        return;
+    }
+
+    liveWriterCts.Cancel();
+    try
+    {
+        liveWriterTask?.Wait(TimeSpan.FromSeconds(2));
+    }
+    catch (AggregateException)
+    {
+        // expected: task cancelled
+    }
+
+    liveWriterCts.Dispose();
+    liveWriterCts = null;
+    liveWriterTask = null;
+}
+
+void LiveWriterLoop(string path, int fileId, CancellationToken token)
+{
+    var name = Path.GetFileName(path);
+    var lineIndex = 0;
+    while (!token.IsCancellationRequested)
+    {
+        try
+        {
+            using var fs = new FileStream(path, FileMode.Append, FileAccess.Write, FileShare.ReadWrite | FileShare.Delete);
+            using var writer = new StreamWriter(fs, Encoding.UTF8);
+            writer.WriteLine(BuildLine(fileId, ++lineIndex, name));
+        }
+        catch (IOException)
+        {
+            // file may be momentarily inaccessible during a D-press; just keep
+            // trying so writes resume once it reappears.
+        }
+
+        try
+        {
+            Task.Delay(liveWriterDelayMs, token).Wait(token);
+        }
+        catch (OperationCanceledException)
+        {
+            return;
+        }
+        catch (AggregateException)
+        {
+            return;
+        }
+    }
+}
+
 string BuildLine(int fileId, int lineIndex, string fileName)
 {
     var baseText = $"{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff} [INFO] File#{fileId:D3} Line {lineIndex:D3} - {fileName} - Sample log message";