Testing PAP handling changes.

LightlessSync/FileCache/FileCacheManager.cs

@@ -27,6 +27,7 @@ public sealed class FileCacheManager : IHostedService
     private readonly ConcurrentDictionary<string, ConcurrentDictionary<string, FileCacheEntity>> _fileCaches = new(StringComparer.Ordinal);
     private readonly ConcurrentDictionary<string, FileCacheEntity> _fileCachesByPrefixedPath = new(StringComparer.OrdinalIgnoreCase);
     private readonly SemaphoreSlim _getCachesByPathsSemaphore = new(1, 1);
+    private readonly SemaphoreSlim _evictSemaphore = new(1, 1);
     private readonly Lock _fileWriteLock = new();
     private readonly IpcManager _ipcManager;
     private readonly ILogger<FileCacheManager> _logger;
@@ -226,13 +227,23 @@ public sealed class FileCacheManager : IHostedService
             var compressed = LZ4Wrapper.WrapHC(raw, 0, raw.Length);
 
             var tmpPath = compressedPath + ".tmp";
-            await File.WriteAllBytesAsync(tmpPath, compressed, token).ConfigureAwait(false);
-            File.Move(tmpPath, compressedPath, overwrite: true);
+            try
+            {
+                await File.WriteAllBytesAsync(tmpPath, compressed, token).ConfigureAwait(false);
+                File.Move(tmpPath, compressedPath, overwrite: true);
+            }
+            finally
+            {
+                try { if (File.Exists(tmpPath)) File.Delete(tmpPath); } catch { /* ignore */ }
+            }
 
-            var compressedSize = compressed.LongLength;
+            var compressedSize = new FileInfo(compressedPath).Length;
             SetSizeInfo(hash, originalSize, compressedSize);
             UpdateEntitiesSizes(hash, originalSize, compressedSize);
 
+            var maxBytes = GiBToBytes(_configService.Current.MaxLocalCacheInGiB);
+            await EnforceCacheLimitAsync(maxBytes, token).ConfigureAwait(false);
+
             return compressed;
         }
         finally
@@ -877,6 +888,83 @@ public sealed class FileCacheManager : IHostedService
         }, token).ConfigureAwait(false);
     }
 
+    private async Task EnforceCacheLimitAsync(long maxBytes, CancellationToken token)
+    {
+        if (string.IsNullOrWhiteSpace(CacheFolder) || maxBytes <= 0) return;
+
+        await _evictSemaphore.WaitAsync(token).ConfigureAwait(false);
+        try
+        {
+            Directory.CreateDirectory(CacheFolder);
+
+            foreach (var tmp in Directory.EnumerateFiles(CacheFolder, "*" + _compressedCacheExtension + ".tmp"))
+            {
+                try { File.Delete(tmp); } catch { /* ignore */ }
+            }
+
+            var files = Directory.EnumerateFiles(CacheFolder, "*" + _compressedCacheExtension, SearchOption.TopDirectoryOnly)
+                .Select(p => new FileInfo(p))
+                .Where(fi => fi.Exists)
+                .OrderBy(fi => fi.LastWriteTimeUtc)
+                .ToList();
+
+            long total = files.Sum(f => f.Length);
+            if (total <= maxBytes) return;
+
+            foreach (var fi in files)
+            {
+                token.ThrowIfCancellationRequested();
+                if (total <= maxBytes) break;
+
+                var hash = Path.GetFileNameWithoutExtension(fi.Name);
+
+                try
+                {
+                    var len = fi.Length;
+                    fi.Delete();
+                    total -= len;
+                    _sizeCache.TryRemove(hash, out _);
+                }
+                catch (Exception ex)
+                {
+                    _logger.LogWarning(ex, "Failed to evict cache file {file}", fi.FullName);
+                }
+            }
+        }
+        finally
+        {
+            _evictSemaphore.Release();
+        }
+    }
+
+    private static long GiBToBytes(double gib)
+    {
+        if (double.IsNaN(gib) || double.IsInfinity(gib) || gib <= 0)
+            return 0;
+
+        var bytes = gib * 1024d * 1024d * 1024d;
+
+        if (bytes >= long.MaxValue) return long.MaxValue;
+
+        return (long)Math.Round(bytes, MidpointRounding.AwayFromZero);
+    }
+
+    private void CleanupOrphanCompressedCache()
+    {
+        if (string.IsNullOrWhiteSpace(CacheFolder) || !Directory.Exists(CacheFolder))
+            return;
+
+        foreach (var path in Directory.EnumerateFiles(CacheFolder, "*" + _compressedCacheExtension))
+        {
+            var hash = Path.GetFileNameWithoutExtension(path);
+            if (!_fileCaches.ContainsKey(hash))
+            {
+                try { File.Delete(path); }
+                catch (Exception ex) { _logger.LogWarning(ex, "Failed deleting orphan {file}", path); }
+            }
+        }
+    }
+
     public async Task StartAsync(CancellationToken cancellationToken)
     {
         _logger.LogInformation("Starting FileCacheManager");
@@ -1060,6 +1148,8 @@ public sealed class FileCacheManager : IHostedService
             {
                 await WriteOutFullCsvAsync(cancellationToken).ConfigureAwait(false);
             }
+
+            CleanupOrphanCompressedCache();
         }
 
         _logger.LogInformation("Started FileCacheManager");