fix: config traversal, timer rethrow, stack-trace reset, lock scope (MAPCO-11323)

MergerLogic/Clients/HeartbeatClient.cs

@@ -84,8 +84,9 @@ public void Send(object? sender, ElapsedEventArgs elapsedEventArgs)
             }
             catch (Exception e)
             {
+                // Elapsed runs on a timer thread; the Timer discards anything thrown here and an
+                // unhandled exception can tear down the process. Log and let the next tick retry.
                 this._logger.LogError($"[{MethodBase.GetCurrentMethod().Name}] Could not send heartbeat for task={this._taskId}, {e.Message}");
-                throw;
             }
         }
     }

MergerLogic/Clients/S3Client.cs

@@ -75,13 +75,13 @@
                     return null;
                 }
                 // In case there are other errors such as connection to S3
-                throw e;
+                throw;
             }
         }
 
         public override Tile? GetTile(int z, int x, int y)
         {
             string methodName = MethodBase.GetCurrentMethod().Name;
             this._logger.LogDebug($"[{methodName}] start z: {z}, x: {x}, y: {y}");
             string keyPrefix = this._pathUtils.GetTilePath(this.path, z, x, y, TileFormat.Jpeg, true);
 
@@ -102,7 +102,7 @@
 
         public Tile? GetTile(string key)
         {
             string methodName = MethodBase.GetCurrentMethod().Name;
             this._logger.LogDebug($"[{methodName}] start key: {key}");
             byte[]? imageBytes = this.GetImageBytes(key);
             if (imageBytes == null)
@@ -117,7 +117,7 @@
 
         public override bool TileExists(int z, int x, int y)
         {
             string methodName = MethodBase.GetCurrentMethod().Name;
             this._logger.LogDebug($"[{methodName}] start z: {z}, x: {x}, y: {y}");
             bool exists = this.GetTileKey(z, x, y) != null;
             this._logger.LogDebug($"[{methodName}] end z: {z}, x: {x}, y: {y}");
@@ -126,7 +126,7 @@
 
         public void UpdateTile(Tile tile)
         {
             string methodName = MethodBase.GetCurrentMethod().Name;
             this._logger.LogDebug($"[{methodName}] start {tile.ToString()}");
             string key = this._pathUtils.GetTilePath(this.path, tile, true);
 
@@ -151,7 +151,7 @@
 
         private string? GetTileKey(int z, int x, int y)
         {
             string methodName = MethodBase.GetCurrentMethod().Name;
             string keyPrefix = this._pathUtils.GetTilePathWithoutExtension(this.path, z, x, y, true);
 
             try
@@ -169,7 +169,7 @@
                     return null;
                 }
                 // In case there are other errors such as connection to S3
-                throw e;
+                throw;
             }
         }
     }

MergerLogic/DataTypes/Fs.cs

@@ -16,7 +16,7 @@ public class FS : Data<IFileClient>
         private IFileSystem _fileSystem;
 
         private readonly string[] _supportedFileExtensions = { ".png", ".jpg", ".jpeg" };
-        static readonly object _locker = new object();
+        private readonly object _locker = new object();
 
         public FS(IPathUtils pathUtils, IServiceProvider container, string path, int batchSize, Grid? grid, GridOrigin? origin, bool isBase = false)
             : base(container, DataType.FOLDER, path, batchSize, grid, origin, isBase)

MergerLogic/DataTypes/Gpkg.cs

@@ -11,7 +11,7 @@ public class Gpkg : Data<IGpkgClient>
         private long _offset;
         private Extent _extent;
         private readonly IConfigurationManager _configManager;
-        static readonly object _locker = new object();
+        private readonly object _locker = new object();
 
         public Gpkg(IConfigurationManager configuration, IServiceProvider container,
             string path, int batchSize, Grid? grid, GridOrigin? origin, bool isBase = false, Extent? extent = null)

MergerLogic/DataTypes/S3.cs

@@ -17,7 +17,7 @@ public class S3 : Data<IS3Client>
         private IEnumerator<int> _zoomEnumerator;
         private string? _continuationToken;
         private bool _endOfRead;
-        static readonly object _locker = new object();
+        private readonly object _locker = new object();
         private const string nullStringValue = "Null";
 
         private readonly IPathUtils _pathUtils;

MergerLogic/Utils/ConfigurationManager.cs

@@ -25,12 +25,8 @@ public ConfigurationManager(ILogger<ConfigurationManager>? logger)
 
         public IEnumerable<IConfigurationSection> GetChildren(params string[] configPath)
         {
-            var config = this.config.GetSection(configPath[0]);
-            for (int i = 1; i < configPath.Length - 1; i++)
-            {
-                config = this.config.GetSection(configPath[i]);
-            }
-            return config.GetSection(configPath[configPath.Length - 1]).GetChildren();
+            string key = string.Join(":", configPath);
+            return this.config.GetSection(key).GetChildren();
         }
 
         public string GetConfiguration(params string[] configPath)